VOLUME 14 NUMBER 1 PAGES 1–116 February 2009
Editors
International Advisory Board
Ann Moore PhD, GradDipPhys, FCSP, CertEd, FMACP Clinical Research Centre for Health Professions University of Brighton Aldro Building, 49 Darley Road Eastbourne BN20 7UR, UK Gwendolen Jull PhD, MPhty, Grad Dip ManTher, FACP Department of Physiotherapy University of Queensland Brisbane QLD 4072, Australia
K. Bennell (Victoria, Australia) K. Burton (Huddersfield, UK) B. Carstensen (Frederiksberg, Denmark) M. Coppieters (Queensland, Australia) E. Cruz (Setubal Portugal) L. Danneels (Maríakerke, Belgium) S. Durrell (London, UK) S. Edmondston (Perth, Australia) J. Endresen (Flaktvei, Norway) L. Exelby (Biggleswade, UK) D. Falla (Aalborg, Denmark) J. Greening (London, UK) C. J. Groen (Utrecht,The Netherlands) A. Gross (Hamilton, Canada) T. Hall (West Leederville, Australia) W. Hing (Auckland, New Zealand) M. Jones (Adelaide, Australia) S. King (Glamorgan, UK) B.W. Koes (Amsterdam,The Netherlands) J. Langendoen (Kempten, Germany) D. Lawrence (Davenport, IA, USA) D. Lee (Delta, Canada) R. Lee (London, UK) C. Liebenson (Los Angeles, CA, USA) L. Maffey-Ward (Calgary, Canada) E. Maheu (Quebec, Canada) C. McCarthy (Coventry, UK) J. McConnell (Northbridge, Australia) S. Mercer (Queensland, Australia) D. Newham (London, UK) J. Ng (Hung Hom, Hong Kong) S. O’Leary (Queensland, Australia) L. Ombregt (Kanegem-Tielt, Belgium) N. Osbourne (Bournemouth, UK) M. Paatelma (Jyvaskyla, Finland) N. Petty (Eastbourne, UK) A. Pool-Goudzwaard (The Netherlands) M. Pope (Aberdeen, UK) G. Rankin (London, UK) D. Reid (Auckland, New Zealand) A. Rushton (Birmingham, UK) C. Shacklady (Manchester, UK) M. Shacklock (Adelaide, Australia) D. Shirley (Lidcombe, Australia) V. Smedmark (Stenhamra, Sweden) W. Smeets (Tongeren, Belgium) C. Snijders (Rotterdam,The Netherlands) R. Soames (Dundee, UK) P. Spencer (Barnstaple, UK) M. Sterling (St Lucia, Australia) P. Tehan (Victoria, Australia) M. Testa (Alassio, Italy) M. Uys (Tygerberg, South Africa) P. van der Wurff (Doorn,The Netherlands) P. van Roy (Brussels, Belgium) B.Vicenzino (St Lucia, Australia) H.J.M. Von Piekartz (Wierden,The Netherlands) M. Wallin (Spanga, Sweden) M. Wessely (Paris, France) A. Wright (Perth, Australia) M. Zusman (Mount Lawley, Australia)
Associate Editor’s Darren A. Rivett PhD, MAppSc, (ManipPhty) GradDipManTher, BAppSc (Phty) Discipline of Physiotherapy Faculty of Health The University of Newcastle Callaghan, NSW 2308, Australia E-mail:
[email protected] Tim McClune D.O. Spinal Research Unit. University of Huddersfield 30 Queen Street Huddersfield HD12SP, UK E-mail:
[email protected]
Editorial Committee Deborah Falla PhD, BPhty(Hons) Department of Health Science and Technology Aalborg University Fredrik BajersVej 7, D-3 DK-9220 Aalborg Denmark Email:deborahfvhst.aau.dk Timothy W Flynn PhD, PT, OCS, FAAOMPT RHSHP-Department of Physical Therapy Regis University Denver, CO 80221-1099 USA Email:
[email protected] Masterclass Editor Karen Beeton PhD, MPhty, BSc(Hons), MCSP MACP ex officio member Associate Head of School (Professional Development) School of Health and Emergency Professions University of Hertfordshire College Lane Hatfield AL10 9AB, UK E-mail:
[email protected] Case reports & Professional Issues Editor Jeffrey D. Boyling MSc, BPhty, GradDipAdvManTher, MCSP, MErgS Jeffrey Boyling Associates Broadway Chambers Hammersmith Broadway London W6 7AF, UK E-mail:
[email protected] Book Review Editor Raymond Swinkels MSc, PT, MT Ulenpas 80 5655 JD Eindoven The Netherlands E-mail:
[email protected]
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Manual Therapy 14 (2009) 1 www.elsevier.com/math
Editorial
New Year wishes Welcome to the 14th volume of Manual Therapy Journal and a Happy 2009 to all our readers. This year sees the expansion of our Editorial Board to now include Tim Flynn who takes on responsibility for ‘‘review’’ and ‘‘systematic review’’ articles and Deborah Falla who has taken up an Associate Editor role. In 2008 we said goodbye to Darren Rivett who had served on the Editorial Board of Manual Therapy Journal for ten years, but whose professional/academic role at the University of Newcastle, Australia had left him little time to work on Manual Therapy Journal matters. We would like to thank Darren, particularly for all his valuable and sustained work for Manual Therapy Journal over the ten-year period. He will be sorely missed, but he has agreed to take a very active role as an Editorial Advisory Board member. 2008 also saw the resignation of Marina Wallin and Venke Smedmark from the Editorial Advisory Board of the Journal. They had both been on the Editorial Advisory Board since the Journal was created in 1995 and we thank them both for their advocacy for the Journal over this fifteen-year period. We would like to express a warm welcome to all new Editorial Advisory Board members. Time now for all readers to look forward to the next range of international conferences: - the Kinetic Control and MACP Movement Dysfunction conference to be held in Edinburgh in 2009,
1356-689X/$ - see front matter Ó 2008 Published by Elsevier Ltd. doi:10.1016/j.math.2008.12.002
- The World Congress of Physical Therapy to be held in Amsterdam in 2011 and; - IFOMT to be held in 2012 in Quebec, Canada. So time to plan attendance at these events now and think about what new research findings you will have to present at these conferences and what CPD opportunities you might take up from the conference programmes. It is interesting now to think what issues will be on the international agenda for Manual Therapists over the next four years, for example: public health, obesity, chronic diseases? and what the balance of research presentations will be in relation to qualitative and quantitative research. Hopefully we will be seeing a rise in cost effectiveness studies and also studies which explore the patient’s experience as well as more studies that underpin our choice of frequency and dosage in relation to treatment applications. We may also see more pedagogic research to underpin how Manual Therapists are educated in Higher Education and in practice. As usual, all the conferences will offer a wonderful opportunity for meeting up with old colleagues, making new friends and acquaintances and forming collaborations across the World. We wish you a very Happy and Prosperous 2009. Ann Moore* Gwendolen Jull *Tel./fax: þ44 1273 643766. E-mail address:
[email protected]
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Manual Therapy 14 (2009) 2 www.elsevier.com/math
List of reviewers 2008 J. Haxby Abbott Caroline Alexander Trevor Allen Caroline Appel Jeff Baghurst Chris Barnett David Baxter Iain Beith Kim Bennell Jon Blacktop Elizabeth Bryant Barbara Cagnie Melinda Cairns Dawn Carnes Elizabeth Cheek Thomas Chiu Jacek Cholewicki Michael Cibulka Ann Cools Michel Coppieters Duncan Critchley Wim Dankaerts Lieven Danneels Anna Dawson Krysia Dziedzic Steven J. Edmondston Jorge Esteves David Evans Darrell Evans Linda Exelby Cesar Fernandez de las Penas Laura Finucane Timothy Flynn Jamie French Angela Glynn Anita Gross Toby Hall Michelle Harms Emma Healey Nicola Heneghan Lee Herrington
1356-689X/$ - see front matter doi:10.1016/j.math.2008.12.001
Jonathan Hill Di Hopper Ian Horsley Alan Hough Anne Jackson Susan Jeno Kajsa Johansson Venerina Johnston Andrew Kerr Roger Kerry Mike Kondracki Birgit Kristensen Raija Kuisma Jennifer Langworthy Mark Laslett Diana Lawrence-Watt Janine Leach Diane Lee Raymond Lee Jeremy Lewis Jiu Jenq Lin Gail Louw Nick Lucas Mary Magarey Dennis Martin Tom McCarron Chris McCarthy Jenny McConnell Suzanne McDonough Alison McGregor Chris Mercer Stephan Milosavljevic Robert Moran Lorimer Moseley Donald Murphy Joseph Ng Shaun O’Leary Neil Osborne Peter Osmotherly Kieran O’Sullivan Johan Pel
Nick Penny Jan Pool Annelies Pool-Goudzwaard Louise Potter Christopher Powers Gabrielle Rankin Kathryn Refshauge Barbara Richardson Colette Ridehalgh Darren Rivett Alison Rushton Paddy Searle-Barnes Michael Shacklock Gary Shum Julius Sim Helen Slater Andrew Smith Suzanne Snodgrass Tina Souvlis Meena Sran Michele Sterling Graham Stew Mark Stigant Maria Stokes Jenny Strong Britt Stuge Annette Swinkels Grace Szeto Paul Tofts Julia Treleaven Michael Troke Neil Tuttle Bill Vicenzino Benedict Wand Hsing-Kuo Wang Peter Watt Chris Wright Jo Zamani Max Zusman
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Masterclass
From acute musculoskeletal pain to chronic widespread pain and fibromyalgia: Application of pain neurophysiology in manual therapy practice Jo Nijs a,b,*, Boudewijn Van Houdenhove c b
a Department of Human Physiology, Faculty of Physical Education and Physiotherapy, Vrije Universiteit Brussels, Belgium Division of Musculoskeletal Physiotherapy, Department of Health Care Sciences, University College Antwerp, Van Aertselaerstraat 31, B-2170 Merksem, Belgium c Faculty of Medicine, Katholieke Universiteit Leuven, Belgium
Received 4 December 2007; accepted 9 March 2008
Abstract During the past decade, scientific research has provided new insight into the development from an acute, localised musculoskeletal disorder towards chronic widespread pain/fibromyalgia (FM). Chronic widespread pain/FM is characterised by sensitisation of central pain pathways. An in-depth review of basic and clinical research was performed to design a theoretical framework for manual therapy in these patients. It is explained that manual therapy might be able to influence the process of chronicity in three different ways. (I) In order to prevent chronicity in (sub)acute musculoskeletal disorders, it seems crucial to limit the time course of afferent stimulation of peripheral nociceptors. (II) In the case of chronic widespread pain and established sensitisation of central pain pathways, relatively minor injuries/trauma at any locations are likely to sustain the process of central sensitisation and should be treated appropriately with manual therapy accounting for the decreased sensory threshold. Inappropriate pain beliefs should be addressed and exercise interventions should account for the process of central sensitisation. (III) However, manual therapists ignoring the processes involved in the development and maintenance of chronic widespread pain/FM may cause more harm then benefit to the patient by triggering or sustaining central sensitisation. Ó 2008 Elsevier Ltd. All rights reserved. Keywords: Fibromyalgia; Central sensitisation; Whiplash; Chronic fatigue syndrome
1. Introduction The 1990 American College of Rheumatology criteria for the classification of fibromyalgia (FM) define chronic widespread pain as a history of at least 3 months of axial skeletal pain, pain in the right and left sides of the body, and pain above and below the waist (Wolfe * Corresponding author. Division of Musculoskeletal Physiotherapy, Department of Health Care Sciences, University College Antwerp, Van Aertselaerstraat 31, B-2170 Merksem, Belgium. Tel.: þ32 3 6418265; fax: þ32 3 641827. E-mail address:
[email protected] (J. Nijs). 1356-689X/$ - see front matter Ó 2008 Elsevier Ltd. All rights reserved. doi:10.1016/j.math.2008.03.001
et al., 1990). In addition to the presence of chronic widespread pain, pain in 11 of 18 tender point sites must be present on digital palpation with an approximate force of 4 kg (Wolfe et al., 1990). FM is classified as a rheumatic illness and is often treated by manual therapists. In the United States, patients with FM are frequently seen in chiropractic practice. Studying the health-care use of 402 patients from a university-based clinic, it was found that nearly 56% of the patients fulfilling the diagnostic criteria for both FM and the related chronic fatigue syndrome visited chiropractors, and 32% of the primary FM subjects consulted chiropractors (Bombardier and Buchwald, 1996). Trigger point
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injections, joint manipulation, and myofascial release techniques are among the more commonly used modalities in the treatment of FM (Clauw, 2007). Although these treatment modalities are currently not evidencebased, this does not imply that manual therapy cannot benefit people with FM. The question arises, however, which rationale can be formulated for applying manual therapy to people with chronic widespread pain/FM? During the past decade, scientific research has provided new insights into the development from an acute, localised musculoskeletal disorder (e.g. a whiplash trauma) towards chronic widespread pain/FM. Understanding these processes might enable manual therapists to develop a theoretical rationale for using manual therapy in the prevention of chronicity and for the treatment of chronic widespread pain/FM. The present manuscript intends to provide such a theoretical framework. The development from an acute, localised musculoskeletal pain problem towards chronic widespread pain/FM is explained and applied to the practice of manual therapy, to explore how manual therapy might be able to influence this process in three different ways. (I) Manual therapy, when applied successfully to acute musculoskeletal disorders, might have the capacity to prevent chronicity. Conversely, when manual therapists ignore the processes involved in the development and maintenance of chronic widespread pain/FM, then they may cause more harm than benefit to the patient. (II) The manuscript explores how the application of manual therapy to (sub)acute musculoskeletal disorders should account for the processes involved in the chronicity of pain. (III) Finally, the manuscript explains that besides its role in primary prevention of chronicity, manual therapy might have its place in the comprehensive management of those with chronic widespread pain/FM. In the next section, the neurophysiology of central sensitisation is briefly introduced. The body of the manuscript consists of six sections each dealing with a different aspect of manual therapy in those at risk of/with chronic widespread pain and FM.
2. Theoretical background: central sensitisation It is important to understand that not all nociceptive signals are perceived as pain, and not every pain sensation originates from nociception. Nevertheless, acute pain almost always originates from nociceptors in somatic or visceral tissue. However, when the nociceptors keep on ‘firing’ nociceptive impulses, the dorsal horn neurons may become hypersensitive (Baranauskas and Nistri, 1998; Staud and Smitherman, 2002). This increased neuronal responsiveness is accomplished by neurotransmitters like glutamate, aspartate and substance P, which modulate the postsynaptic electric discharges
with further transmission to supraspinal sites (thalamus, anterior cingulate cortex, insular cortex, and somatosensory cortex) via ascending pathways (Staud and Smitherman, 2002). The neurotransmitters initiate increased postsynaptic responses by triggering hyperexcitability of N-methyl-D-aspartate (NMDA) receptor sites of second-order neurons in the dorsal horn (Fig. 1). This mechanism is related to temporal summation of second pain or wind-up. Wind-up refers to the progressive increase of electrical discharges from the second-order neuron in the spinal cord in response to repetitive Cfibre stimulation, and is experienced in humans as increased pain (Mendell and Wall, 1965; Gracely et al., 2004; Staud et al., 2007). Wind-up is part of the process known as central sensitisation (Meeus and Nijs, 2007). When manual therapists apply hands-on techniques, and by doing so elicit identical nociceptive stimuli to the skin, muscles or joint capsules more often than once every 3 s, they are likely to trigger this mechanism of pain amplification. Central sensitisation is defined as ‘‘an augmentation of responsiveness of central pain-signalling neurons to input from low-threshold mechanoreceptors’’ (Meyer et al., 1995). While peripheral sensitisation is a local phenomenon, central sensitisation means that central pain processing pathways localised in the spinal cord and the brain are sensitised. Indeed, the process of central sensitisation is neither limited to the dorsal horn, nor to pain amplification of afferent impulses. Central sensitisation encompasses altered sensory processing in the brain and malfunctioning of pain-inhibitory mechanisms. Coding of the mechanism of wind-up involves multiple brain sites, including somatosensory (thalamus, anterior insula, posterior insula, primary somatic sensory cortex, and secondary somatic sensory cortex), cognitiveeevaluative/affective (anterior cingulate cortex and prefrontal cortex), and pain-modulating regions (rostral anterior cingulate cortex) (Staud et al., 2007). The elevated central nervous system reactivity inhibits functioning of regulatory pathways for the autonomic, endocrine and the immune system (Bell et al., 1998). Activation of certain regions of the midbrain activates extremely powerful descending pain-modulating pathways that project, via the medulla, to neurons in the dorsal horn that control the ascending information in the nociceptive system (Purves et al., 1997). These pain-inhibitory pathways arise mainly from the periaqueductal grey matter and the rostral ventral medulla in the brainstem (Purves et al., 1997). One function of the descending inhibitory pathway is to ‘‘focus’’ the excitation of the dorsal horn neurons by suppressing surrounding neuronal activity (Woolf and Salter, 2000), a role attributed to the ‘‘diffuse noxious inhibitory controls’’ phenomenon (Le Bars and Villaneuva, 1988). In the case of central sensitisation and chronic widespread pain these descending pain-inhibitory pathways are malfunctioning (Fig. 1)
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brain: malfunctioning of central pain inhibitory pathways arising from periaquaductal gray matter and rostral ventral medulla in brainstem
PAIN
brain: cognitive-emotional sensitisation brain: sensory-motor conflict
overactive ascending pain fascilatory pathways
malfunctioning of descending pain-modulating pathways dorsal horn: hyperexcitability of NMDA-receptor sites of second-order neurons & progressive increase in discharges from second-order neurons
spinal cord
injury / trauma / arthritis peripheral tissues: enhanced responsiveness of nociceptive endings Fig. 1. Anatomical localisations of hyperexcitability of peripheral and central pain pathways.
(Staud et al., 2001; Price et al., 2002; Banic et al., 2004). Malfunctioning of central pain-inhibitory pathways in people with chronic pain becomes particularly apparent to clinicians during exercise interventions: both isometric and aerobic exercises activate endogenous opoid and adrenergic pain-inhibitory mechanisms in healthy subjects, while it increases experimental pain ratings in patients with FM (Staud et al., 2005) and chronic fatigue syndrome (Whiteside et al., 2004). So how do we account for the process of central sensitisation during manual treatment of those with musculoskeletal pain? This will be discussed in the following sections.
3. Manual therapy to prevent hypersensitivity of pain pathways in (sub)acute musculoskeletal pain An important and ongoing source of pain is required before the process of peripheral sensitisation can establish central sensitisation. It seems crucial to limit the time course of afferent stimulation of peripheral nociceptors: tissue injury healing and focal pain recovery should occur within a period of approximately 3 months to prevent development of chronic widespread pain/FM (Vierck, 2006). Progression towards chronic widespread pain is associated with injuries to deep tissues which do not heal within several months (Vierck, 2006). Consequently, appropriate and effective manual therapy in those with (sub)acute musculoskeletal disorders is important to prevent evolvement from an acute, localised
musculoskeletal pain problem to complex clinical cases, characterised by chronic widespread pain and even symptoms outside the musculoskeletal system such as increased sensitivity to bright lights, auditory loudness, odours, and other sensory stimuli. Pain due to damage or inflammation of peripheral tissues is clearly capable of causing chronic widespread pain/FM (Clauw, 2007). 15e20% people with whiplash injuries develop chronic pain and disability (Spitzer et al., 1995; Radanov and Sturzenegger, 1996; Coˆte´ et al., 2001). Regardless of whether FM is present in chronic whiplash, altered central pain processing and central sensitisation is evident (Curatolo et al., 2001; Sterling et al., 2002, 2003, 2006; Banic et al., 2004). Moreover, altered central pain processing rather than impaired motor control has been identified as one of the prime prognostic factors for developing chronic whiplash (Sterling et al., 2003, 2006). Another example of a local musculoskeletal disorder associated with FM and frequently seen in manual therapy practice is arthritis (rheumatoid arthritis and osteoarthritis), possibly causing continuous activation of local nociceptors that initiate or sustain central sensitisation (Yunus, 2007). Thus, effective manual therapy in (sub)acute cases of arthritis should be able to limit the (time course of) afferent barrage of noxious input to the central nervous system and thus prevent chronicity. In addition, manual therapy aimed at improving motor control in symptomatic regions/joints is likely to have its place in the prevention of chronicity. Indeed, a sustained mismatch between motor activity and
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sensory feedback is able to serve as an ongoing source of nociception inside the central nervous system. There is evidence that a mismatch between motor activity and sensory feedback can elicit pain and sensory perceptions in healthy pain-free volunteers (McCabe et al., 2005) and exacerbate pain and sensory perceptions in patients with FM (McCabe et al., 2007), suggesting a possible aetiological role for sensoryemotor incongruence in the development of (chronic) pain. The role of the motor control system in the brain is to manage the relationship between motor commands and sensory feedback (proprioception, vision). In case of inaccurate execution of movements due to deconditioning or joint tissue damage (and consequent altered proprioception), an incongruence between motor activity and sensory feedback is likely to occur. The motor control system may alert the individual to the abnormality in information processing by generating warning signals (i.e. pain or other sensory changes like temperature change or a feeling of peculiarity) (McCabe et al., 2005). Apart from manual therapy skills targeting local musculoskeletal disorders, manual therapy in its broader sense (including stress management, pain physiology education, etc.) has its place in the prevention of chronic widespread pain and FM. These issues are explained below, together with the explanation of the role of manual therapy in those with established hypersensitivity of central pain pathways.
any adverse reactions to the interventions immediately and to adapt their (home) exercises accordingly (Fig. 2). 4.1. Myofascial treatment Anecdotally, muscles and fascia often become hypertonic and develop trigger points in people with chronic widespread pain/FM. Soft-tissue mobilisation is required to free up restrictions and restores local blood flow. However, it is important not to increase pain during treatment. The vicinity of myofascial trigger points differs from normal muscle tissue by its lower pH levels (i.e. more acid), increased levels of substance P, calcitonin gene-related peptide, tumour necrosis factor-a and interleukine-1b, each of which has its role in increasing pain sensitivity (Shah et al., 2005). Sensitised muscle nociceptors are more easily activated and may respond to normally innocuous and weak stimuli such as light pressure and muscle movement (Shah et al., 2005). Therefore, starting the soft-tissue mobilisation superficially with well-tolerated strokes along the length of the muscle fibres (referred to as ‘stripping’ in Benjamin and Tappan, 2005) and progressing towards deeper strokes that go perpendicular to the soft-tissue fibres is recommended (Table 1). Aggressive ways of treating trigger points (e.g. by using ischaemic pressure) are usually not welltolerated and therefore not recommended. 4.2. Motor control training
4. Manual therapy targeting local problems in patients with central sensitisation In cases of hypersensitivity of central pain pathways, relatively minor injuries/trauma at any locations are likely to sustain the process of central sensitisation (Vierck, 2006). In these patients, local musculoskeletal problems are more than epiphenomenona and serve as a continuous source of afferent painful barrage (Nijs et al., 2006). Appropriate manual physiotherapy is unlikely to cure the chronic widespread pain, but can still resolve the localised musculoskeletal pain problem and thus decrease afferent barrage (Nijs et al., 2006). However, clinicians should be aware of the consequences of central sensitisation (i.e. a marked reduced sensory threshold) and adapt their hands-on techniques and exercise programs accordingly. Any therapeutic interventions triggering more pain will serve as a new peripheral source of nociceptive barrage and thus will sustain the process of central sensitisation, as evidenced by the study in patients with FM showing that altered central pain processing is further augmented by isometric exercise (Staud et al., 2005). Likewise, treatments triggering more pain serve as a physical stressor attacking the already deregulated stress response system, thereby initiating a vicious cycle. It is therefore crucial to educate the patient to report
In line with the findings in those with phantom limb pain (Flor et al., 2001), it seems plausible to improve appropriate sensory feedback by using local motor control training to account for the sensoryemotor conflict capable of exaggerating local FM symptoms (McCabe et al., 2005, 2007). Local motor control training is the core feature of the treatment of joint hypermobility. Since FM primarily affects the central nervous system, joint treatment is secondary. Still, there is consistent evidence that generalised joint hypermobility is more prevalent in people with FM compared to healthy controls (AcususoDiaz and Collantes-Estevez, 1998; Hudson et al., 1998; Karaaslan et al., 2000). Combining the prevalence rates of the various studies generates a prevalence rate of 21% (Nijs, 2005), supporting the notion that at least a subgroup of FM has generalised joint hypermobility (Fitzcharles, 2000). Hypermobility has been suggested to account, at least in part, for the widespread pain in FM patients (Gedalia et al., 1993; Fitzcharles, 2000). Impaired motor control in end-range movements might lead to recurrent microtrauma and consequent widespread pain in hypermobile patients (Fitzcharles, 2000). In line with this view, generalised joint hypermobility and its repetitive microtrauma might trigger or sustain central sensitisation (Staud, 2004). Joint hypermobility might even lead to a sensoryemotor incongruence and consequent
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7
patient with musculoskeletal pain nature of complaint? acute/subacute pain
chronic localised pain
inappropriate beliefs?
inappropriate beliefs?
no treat local problem with MT*
yes address beliefs + treat local problem with MT below pain threshold
no
yes
treat local address problem beliefs + with MT treat local below pain problem with threshold MT below pain threshold
chronic widespread pain when appropriate: treat local problems with MT below pain threshold pain neurophysiology education treat hypermobility below pain threshold aerobic exercise allowing muscle (re)perfusion, below pain threshold & without post-exertional symptom increase
Fig. 2. Proposed treatment options accounting for central hyperexcitability of central pain pathways. MT, manual therapy.
pain exaggeration. However, there is currently no evidence in support of an association between pain complaints and generalised joint hypermobility in those with FM (Nijs, 2005). In the absence of such evidence, it is recommended to search for such an association on an individual basis. If the manual therapist suspects a role for joint hypermobility in a particular FM case, then a treatment consisting of end-range stabilisation exercises, postural advice, movement advice, self-management strategies and the application of protective and supportive devices is recommended (Nijs, 2005).
5. Changing inappropriate beliefs in an attempt to desensitise the central nervous system Although the dysfunctional descending paininhibitory mechanism as seen in those with chronic widespread pain/FM is primary biological, it is influenced by inappropriate cognitions, emotions and behaviour like catastrophizing, hypervigilance, avoidance behaviour, and somatisation. In case of more intense pain levels, pain catastrophizing is associated with decreased activity in brain regions involved in top-down Table 1 Practical guidelines for hands-on manual therapy skills in those with hypersensitive pain pathways -Educate patient to report adverse reactions during treatment -Do not elicit identical nociceptive stimuli > once every 3 s -Adopt techniques to reduced sensory threshold -Do not increase nociceptive barrage -Initiate soft-tissue mobilisation with superficial stripping techniques -Progress soft-tissue mobilisation with deeper cross-fibre techniques -Careful with ischaemic compression
pain suppression like the dorsolateral prefrontal cortex and the medial prefrontal cortex (Seminowicz and Davies, 2006). In addition to catastrophizing, avoidance behaviour and somatisation may result in sensitisation of dorsal horn spinal cord neurons (through inhibition of descending tracts in the central nervous system e Fig. 1), or alternatively, may be the result of central sensitisation (Zusman, 2002). Sustained arousal is likely to maintain sensitisation of the neurobiological loops (Ursin and Eriksen, 2001). It is important for clinicians to recognise that pain cognitions such as fear of movement and catastrophizing are not only of importance to chronic pain patients, but may even be crucial at the stage of acute/subacute musculoskeletal disorders (Swinkels-Meewisse et al., 2006). So how do you screen for this in daily practice? Screening patients for maladaptive beliefs and subsequently changing them should not be limited to multidisciplinary settings applying cognitive behavioural therapies. Instead, all practitioners can use easy-administered questionnaires (e.g. the pain vigilance and awareness questionnaire, the pain catastrophizing scale) to screen their patients with (sub)acute/chronic musculoskeletal pain for maladaptive beliefs. In the case of hypervigilance, catastrophic beliefs about pain (i.e. helplessness, rumination and magnification) or passive coping strategies like avoidance behaviour, intensive education about the exact nature of chronic widespread pain is likely to clear the path for effective manual physiotherapy (including exercise interventions). Pain neurophysiology education aims at reconceptualising pain, and was found to be effective in reducing pain catastrophising in those with chronic low back pain (Moseley et al., 2004) and chronic widespread pain (Meeus et al., submitted for publication). In
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addition, educating people with FM about central sensitisation of pain pathways was part of a successful rehabilitation program (Mannerkorpi et al., 2000, 2002). If pain cognitions can be changed by educating patients, increased exposure to activity is allowed, leading to increased performances (Watson et al., 1997). Altered pain beliefs leads to increased confidence, which in turn leads to increased activity levels (Moseley, 2005). From the explanation above, it is clear that pain neurophysiology education should be included in the initial phase of rehabilitation in those patients who have inappropriate beliefs about their pain complaints. If not, a poor understanding of pain may lead to the acquisition of maladaptive attitudes, cognitions and behaviour (Geisser and Roth, 1998) and a consequent poor compliance to any active treatments such as exercise interventions.
6. Changing inappropriate beliefs to improve movement performance It seems plausible that improving beliefs like pain catastrophizing is important not only for enabling proper functioning of the central pain-inhibitory pathways, but to improve movement performance as well. In cases where motor control training appears very difficult in those with chronic widespread pain/FM, changing inappropriate beliefs might solve the problem (Moseley, 2005). Indeed, inappropriate cognitions appear closely related to movement performance. In patients with chronic widespread pain, pain catastrophizing is strongly related to physiological exercise variables (Nijs et al., 2008). In subjects with chronic pain, pain physiology education and consequent altered pain beliefs are directly associated with improved movement performance, even if there is no opportunity to be physically active (Moseley, 2004, 2005). These observations make more sense when interpreted in relation to evidence from brain studies: healthy subjects display a relationship between pain catastrophizing and brain activity in regions involved in motor response and motor planning (i.e. thalamus, putamen, and premotor cortex) (Seminowicz and Davies, 2006). In spite of an increasing amount of research in this area, an in-depth understanding of the bidirectional painemotor interaction is still far from being achieved (Le Pera et al., 2007), but has important messages for manual therapy.
7. Stress management to counteract abnormal pain processing We believe that manual therapy in its broader sense (i.e. treatment modalities including relaxation, breathing exercises and stress management) is able to prevent chronicity in many acute/subacute musculoskeletal
pain problems, and has its place in the comprehensive management of chronic widespread pain/FM (Table 2). The available evidence suggests that in FM the stress response system, notably the hypothalamicepituitarye adrenal (HPA) axis and the sympathetic nervous system, is deregulated (Okifuji and Turk, 2002; Crofford et al., 2004; Adler and Geenen, 2005). Some authors have proposed that this might imply a neurobiological ‘switch’ from hyper(re)activity to hypo(re)activity of the stress system, based on functional or even structural receptor changes, and followed by a cascade of disturbances in neurotransmitter functions, immunological and central pain processing mechanisms (Van Houdenhove and Egle, 2004; Fries et al., 2005). More specifically, deficient HPA-axis functioning might foster pathological immune activation with release of pro-inflammatory cytokines (Raison and Miller, 2003) provoking a so-called ‘sickness response’ (lethargia and malaise, social withdrawal, flulike symptoms, mood lowering, concentration difficulties and generalised pain hypersensitivity), all of which characterise the symptom picture of FM (Wallace et al., 2001). Even in healthy fit subjects with reduced baseline HPA-axis activity, decreasing the physical activity level can trigger symptoms (pain, fatigue) (Glass et al., 2004), suggesting a role for the stress system in the development of symptoms in case of reduced activity (McLean et al., 2005). In this respect, it has recently been shown that HPA-axis hypo-function predicted Table 2 Potential treatment goals and treatment modalities for those with chronic widespread pain and FM Treatment goal
Treatment modality
Decrease afferent nociceptive barrage of trigger points
Soft-tissue mobilisation
Improve appropriate sensory Motor control training feedback to prevent sensorye motor conflict Address joint hypermobility
Motor control training þ movement advice þ self-management strategies
Improve inappropriate beliefs (Pain neurophysiology) education (e.g. catastrophizing) Stress management/stress reduction
Relaxation þ stress self-management techniques þ breathing exercises
Decrease fear of movement
Exposure in vivo or low to moderate intensity exercise below pain threshold
Improve exercise capacity
Low to moderate intensity exercise below pain threshold
Improve effort tolerance
Low to moderate intensity exercise below pain threshold
Improve symptoms and daily functioning
Low to moderate intensity exercise below pain threshold
Improve muscular blood flow Low to moderate intensity exercise below pain threshold
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the development of chronic widespread pain in a group of psychologically ‘at risk’ subjects (McBeth et al., 2007). In line with the patients’ history, this abnormal functioning of the stress system seems to occur mostly in the aftermath of a long period of overburdening by physical and/or emotional stressors and to be precipitated by an additional trigger in the form of an acute physical or emotional event (McLean et al., 2005). In those with chronic widespread pain/FM, the inability of the central nervous system to activate the descending pain-inhibitory pathways is likely to be related to the stress system (i.e. the initial stress response to the collision during whiplash trauma and via behavioural changes that occur in response to the trauma) (McLean et al., 2005). The stress system is capable of influencing pain processing via dorsal horn glucocorticoid receptors (receptors having pain-inhibitory capacity) (McLean et al., 2005). However, many unsolved questions remain about the precise role of stress and stress system disturbance in FM (Cleare, 2004).
8. Exercise therapy accounting for central sensitisation There is evidence to support specific exercise therapies as a cornerstone in the comprehensive management of FM (McCain et al., 1988; Isomeri et al., 1993; Burckhardt et al., 1994; Martin et al., 1996; Buckelew et al., 1998; Mannerkorpi et al., 2000; Nijs and Van Parijs, 2004). The evidence from randomised clinical trials is underscored by the conclusions of a systematic literature review (Karjalainen et al., 2000). In relation to the use of exercise therapy, various treatment goals of potential relevance to those with chronic widespread pain and FM can be identified (Table 2) including effort tolerance rather than low effort capacity (Van Houdenhove et al., 2007). However, clinicians should be cautious not to sustain or even amplify the process of central sensitisation. As outlined above, isometric and aerobic exercises activate endogenous opoid and adrenergic pain-inhibitory mechanisms in healthy subjects, while it increases experimental pain ratings in patients with FM (Staud et al., 2005). Thus, people with FM are increasingly susceptible to activation of nociceptors during exercise. As is the case with hands-on manual therapy skills, exercise interventions that are too vigorous are likely to activate muscle and joint nociceptors and thus cause afferent painful barrage. Altered central pain processing is further augmented by isometric exercise (Staud et al., 2005). Post-exertional complaints should be prevented and closely monitored, if not aversive consequences of exercise therapy can arise and may be a deterrent to compliance with the intervention (Dupree Jones et al., 2006; Vierck, 2006). In those with FM, post-exertional complaints are more pronounced than the well documented delayed
9
onset muscle soreness experienced by healthy deconditioned persons without FM who engage in unfamiliar muscle activity. Post-exertional complaints are typically seen in exercise programs using higher intensities, higher impact movements and those where subjects cannot selfadjust exercise intensity (Dupree Jones et al., 2006). Exercises that are too vigorous might trigger immune activation with release of pro-inflammatory cytokines provoking a so-called ‘sickness response’ (Maier and Watkins, 1998), possibly explaining a variety of postexertional complaints. Therefore, low to moderate intensity exercise (approximately 50% of maximum heart rate) of any types has lower attrition and better symptom improvement than those with the higher intensity (Dupree Jones et al., 2006). Further support in favour of mild to moderate exercise over vigorous exercise interventions comes from the study showing a blunted increase in muscular vascularity in response to both dynamic and static contractions (Elvin et al., 2006). This can result in diminishing blood flow towards the working muscles both during and following exercises (Elvin et al., 2006). These data are in line with other observations pointing to widespread muscular ischaemia in patients with FM (reviewed in Vierck, 2006). Since muscle nociceptors are highly sensitive to ischaemia, exercise interventions should account for the widespread muscular ischaemia and blunted increase in muscular vascularity in response to muscle contractions. If not, exercise is likely to increase afferent painful barrage and thus sustain or accelerate the process of central sensitisation. Apart from using mild to moderate exercise intensity, aerobic exercises using multiple recovery periods (to allow muscular reperfusion) within training sessions might be beneficial (Fig. 2). If available, hydrotherapy in warm water, known to be beneficial to those with FM (Mannerkorpi et al., 2000), might even be able to account for the decreased muscle perfusion during exercise (Vierck, 2006).
9. Conclusion Chronic widespread pain/FM is characterised by sensitisation of central pain pathways. An important and ongoing source of pain is required before the process of peripheral sensitisation can establish central sensitisation. Ongoing nociceptive barrage results in adaptation of dorsal horn neurons, and the process of central sensitisation encompasses altered sensory processing in the brain and malfunctioning of pain-inhibitory mechanisms as well. There is evidence that a stress response system dysfunction may play a role in central sensitisation. Moreover, inappropriate cognitions, emotions and behaviour may have a negative impact on the descending pain-inhibitory mechanisms. In order to
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prevent chronicity in acute or subacute musculoskeletal disorders, it seems crucial to limit the time course of afferent stimulation of peripheral nociceptors. In line with this view, it is suggested that manual therapy might have the capacity to prevent chronicity. In the case of chronic widespread pain and established sensitisation of central pain pathways, relatively minor injuries/trauma at any locations are likely to sustain the process of central sensitisation and should be treated appropriately with manual therapy accounting for the decreased sensory threshold. In addition, generalised joint hypermobility might lead to recurrent microtrauma and consequently sustain the process of central sensitisation. Thus, manual therapy appears to have its place in the comprehensive management of those with chronic widespread pain/FM. The role of manual therapy in such patients may not be limited to localised joint and muscle treatment, but encompasses improvement of pain beliefs and exercise therapy as well. Exercise interventions should take the process of central sensitisation into account by using low to moderate intensity, aerobic exercises using multiple recovery periods. Also stress management techniques such as relaxation and breathing exercises may be useful in some cases. However, manual therapists unaware of, or ignoring the processes involved in the development and maintenance of chronic widespread pain/FM, may cause more harm then benefit to the patient by triggering or sustaining central sensitisation. Finally, it should be noted that the proposed role of manual therapy in the management of chronic widespread pain/FM is based on a theoretical framework rather than on evidence from randomised clinical trials. References Acususo-Diaz M, Collantes-Estevez E. Joint hypermobility in patients with fibromyalgia syndrome. Arthritis Care and Research 1998;11:39e42. Adler GK, Geenen R. Hypothalamicepituitaryeadrenal and autonomic nervous system functioning in fibromyalgia. Rheumatic Disease Clinics of North America 2005;31:187e202. Banic B, Petersen-Felix S, Andersen OK, Radanov BP, Villiger PM, Arendt-Nielsen L, et al. Evidence for spinal cord hypersensitivity in chronic pain after whiplash injury and in fibromyalgia. Pain 2004;107:7e15. Baranauskas G, Nistri A. Sensitization of pain pathways in the spinal cord: cellular mechanisms. Progress in Neurobiology 1998;54:349e65. Bell IR, Baldwin CM, Schwartz GE. Illness from low levels of environmental chemicals: relevance to chronic fatigue syndrome and fibromyalgia. American Journal of Medicine 1998;105:74Se82. Benjamin PJ, Tappan FM. Tappan’s handbook of healing massage techniques. Classic, holistic, and emerging methods. New Jersey: Pearson Prentice Hall; 2005. p. 127. Bombardier CH, Buchwald D. Chronic fatigue, chronic fatigue syndrome, and fibromyalgia. Disability and health-care use. Medical Care 1996;34:924e30. Buckelew SP, Conway R, Parker J, Deuser WE, Read J, Witty TE, et al. Biofeedback/relaxation training and exercise interventions
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Available online at www.sciencedirect.com
Manual Therapy 14 (2009) 13e18 www.elsevier.com/math
Original article
Motion analysis study of a scapular orientation exercise and subjects’ ability to learn the exercise Sarah L. Mottram a,*, Roger C. Woledge b, Dylan Morrissey c a KC International, Lower Mill Street, Ludlow, SY8 1BH, UK Centre for Applied Biomedical Research, King’s College London, London SE1 1UL, UK c Centre for Sports and Exercise Medicine, Queen Mary University of London, Mile End Hospital, London E1 4DG, UK b
Received 17 August 2006; received in revised form 25 July 2007; accepted 30 July 2007
Abstract Exercises to retrain the orientation of the scapula are often used by physiotherapists to optimise shoulder girdle function. The movements and muscle activity required to assume this position have not yet been quantified. Further, patients often find this a difficult exercise to learn accurately, with no data being available on the accuracy of repeated performance. The primary objective of this study was to quantify the movements occurring during a commonly used scapular orientation exercise. The secondary objective was to describe the ability of subjects to learn this position after a brief period of instruction. A group of normal subjects (13 subjects; mean age 32, SD¼9) were taught the scapular orientation exercise. Measurement of the position and muscle actions were made with a motion analysis system and surface electromyography. Further comparison was made of the accuracy of repeated trials. The most consistent movements were upward (mean¼4 , SEM¼0.9 ) and posterior rotation (mean¼4 , SEM¼1.6 ). All parts of the trapezius muscle demonstrated significant activity in maintaining the position while latissimus dorsi did not. Repeated trials showed that subjects were able to accurately repeat the movement without guidance. The key movements of, and immediate efficacy of a teaching approach for, scapular orientation have been established. Ó 2007 Elsevier Ltd. All rights reserved. Keywords: Scapula; Motion analysis; Muscle activity; Exercise
1. Introduction Abnormal scapular movement and muscle function have been shown to be important factors associated with shoulder impingement syndrome (Lukasiewicz et al., 1999; Ludewig and Cook, 2000). Exercises to retrain shoulder function are routinely used by physiotherapists as part of a treatment package for patients with scapular dysfunction (Dickens et al., 2005). One such exercise commonly used is teaching scapular orientation with the arm by the side (Mottram, 1997, 2003). The movements and muscle activity required to assume this position have not yet been quantified. * Corresponding author. E-mail address:
[email protected] (S.L. Mottram). 1356-689X/$ - see front matter Ó 2007 Elsevier Ltd. All rights reserved. doi:10.1016/j.math.2007.07.008
The primary objective of this study was to quantify the movements occurring during a scapular orientation exercise (SOE) and normal subjects’ ability to reproduce the position. The secondary objective was to measure the activity in specific muscles in maintaining this movement, particularly the components of the trapezius muscle. 2. The scapular orientation exercise The SOE or previously described as scapula setting (Mottram, 1997, 2003) is taught by physiotherapists in a variety of postures, initially with the arm by the side. It has been described as dynamic orientation of the scapula in order to optimise the position of the glenoid (Mottram, 1997). It is the scapular neutral (mid range)
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position in which there is minimal support from the passive osteo-ligamentous system with the position being maintained by the myofascial structures. A description of this exercise may be of value to the clinician planning the rehabilitation of scapular movement and is necessary in order to evaluate the relationship of this exercise to what is already known about scapular movement faults. Many clinicians find the SOE difficult to teach. A clear description of, and evaluation of a teaching schedule for, scapular orientation will give clinicians a clearer picture of the movements involved and help them adopt a suitable strategy for retraining.
3. Methods 3.1. Subjects The Royal National Orthopaedic Hospital Trust ethics committee granted ethical approval and each subject gave written informed consent. Thirteen subjects were recruited (nine females, four male) aged between 18 and 43 (mean 32, SD 9). All subjects were right handed. Subjects with a history of spinal or upper limb problems that had required treatment or time off work, or any known bony abnormality of the spine (such as a fracture or congenital deformity) were excluded. 3.2. Data collection A motion analysis system, CODA MPX 30 (Charnwood Dynamics, Rothley, UK) was used to collect the motion data. Studies have shown that skin mounted motion sensors are suitable to measure scapula rotation and translation (Johnson and Anderson, 1990; Ludewig and Cook, 2000; Karduna et al., 2001; Lin et al., 2005; Morrissey et al., 2007). The accuracy of all skinmounted marker-tracking systems is inherently limited but satisfactory for the purposes of this study. The CODA uses active infrared LED markers to measure positions within a 223 m3 volume. The translational precision of the instrument has been shown to be within 0.5 mm in each direction, while rotational accuracy is within 1 , determined using factory calibration experiments. Marker positions were captured at 100 Hz. Markers were attached to the thorax (T1, T3, T6), the root of the spine of the scapula, scapula inferior angle and posterior-lateral acromion therefore allowing construction of axis systems in line with ISB recommendations (Karduna et al., 2001). EMG was recorded using a multi-channel EMG system (MA 300 DTU, Motion Lab Systems, Bolton Rouge, LA, USA). Pairs of self-adhesive gelled surface electrodes 1 cm in diameter at 2 cm distance were used.
Preamplifiers were mounted directly over these electrodes and a reference electrode placed over the contra-lateral acromion. EMG was recorded within a bandwidth of 0.2e5.0 kHz and integrated over 5 ms intervals. The resultant values were collated on computer by infrared telemetry at 200 Hz interleaved with the operation of the infrared motion analysis system. The subject was asked to hold the orientated position for 5 s. Records were examined to determine 2 s when the least movement occurred. Scapula position and muscle activity in the orientated position was extracted by the average position or muscle activity during this 2 s period. Scapula movement was defined in relation to the thorax co-ordinate system, using a ZYX Eulerian transform in accordance with ISB recommendations (Karduna et al., 2000). This procedure effectively removed confounding thoracic movement from the results. Translation of the scapula were measured in millimetres and described as lateral (in the frontal plane), ventral (in the sagittal plane) and superior (in the horizontal plane). Rotations of the scapula were measured in degrees and described as upward rotation (in the coronal plane), external rotation (in the transverse plane) and posterior rotation (in the sagittal plane). For movement data, comparison was made between the resting and scapular orientated positions (unassisted). For data pertaining to the accuracy of positioning, comparison was made with the assisted position data (therapist assisting the new scapula positioning). EMG electrode pairs were attached over the upper trapezius centred 2 cm lateral to the midpoint between the seventh cervical vertebrae and the lateral end of the acromion (Jensen et al., 1993); the middle trapezius on the mid point of a line from the acromion to the end of the spinous process of the seventh cervical vertebra (Guazzelli et al., 1991); the lower trapezius 3 cm lateral to the spine at the level of the inferior angle of the scapula (Cherington, 1968); and finally the latissimus dorsi 4 cm below the inferior angle of the scapula (Basmajian and DeLuca, 1985). The electrode placements were in line with the fibre direction for each muscle.
4. Procedure The right shoulder was used in each subject. Subjects were seated on a stool with the feet supported and spine in a neutral position. The subject was taught the SOE by an experienced physiotherapist (primary author). The procedure for teaching the SOE in this experiment has been previously described and is described below (Mottram, 1997, 2003). The SOE position was determined in each individual. In each subject this was judged to be the mid position
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between their available range of upward and downward rotation, external and internal rotation and posterior and anterior rotation (posterioreanterior tilting) of the scapula. The SOE position was established by active movements by the subject assisted by the therapist. The movements required to achieve the SOE (as judged by the therapist) were then explained to the subject and visual, auditory and kinaesthetic cues were used. Different cues were used for different subjects in order to achieve the objective of positioning the scapula actively in the mid neutral region as subjects respond differently to a given cue. Examples of cues included passive/assisted movements into the SOE position, tactile feedback with gentle pressure on the acromion to encourage upward rotation, recognition of a feeling of widening the chest to encourage posterior tilt, demonstration of common wrongly directed movements, demonstration and verbal feedback. The exact instructions given by the therapist were dependent on the judgement of the relaxed position of the scapula, the movement required to achieve the SOE position and the response of the patient to visual, auditory and kinaesthetic cues. A maximum of 5 min was used for the teaching procedure. A record of EMG activity was made as the subjects raised their arm through 150 in the scapular plane. The arm was raised over a 3 s period and lowered over a 3 s period. This produced a clear burst of activity at all four recording sites. Maximum activity within any 0.1 s interval during this movement was used as the standard for normalisation purposes. The normalisation of EMG activity with reference to recording during another movement has been used in other studies (Hungerford et al., 2003; Lehman et al., 2004). All EMG signals were rectified and then averaged over the 2 s period and then divided by the normalisation standard. At rest, markers were attached to the bony landmarks described above and their position recorded. The experimenter next positioned the subject in the orientated position for remarking of the scapular landmarks as described above (assisted). A maximum of 5 min was required for this. Following a recording in this position the subject returned to the resting position. Immediately following this (within 2 min), motion data recordings were taken while the subject made three further attempts to
return to, and hold for 5 s, the scapula orientated position (unassisted). A rest period of 30 s was allowed between these attempts. EMG recording was made on the first unassisted repositioning attempt only. All EMG signals were rectified and then averaged over the 2 s period and then divided by the normalisation standard.
5. Statistical methods All statistics were performed using Sigma Stat 2 (Jandel Scientific, CA, USA). The distribution of the data was tested for normality using the KolmogoroveSmirnov test. Specifically, the Pearson correlation analysis was used for repeated movements, t-tests were used to derive the p-values for the difference between the resting and SOE position and ANOVA for muscle action with Tukey post hoc tests. The level of significance was set at p<0.05.
6. Results 6.1. Scapular position The most consistent movements in the transition from resting to the orientated position (assisted) were upward and posterior rotation, which differed significantly from the resting position. All translations in each dimension and rotation in the horizontal plane (Table 1) showed no significant difference from the resting position, possibly reflecting a variety of subject resting positions and therefore strategies required to get to the scapular orientated position. The rotations in the sagittal and coronal plane for each subject are shown in Fig. 1. 6.2. Muscle activity Fig. 2 shows the average EMG activity recorded during a still period of 2 s during which the orientated position was held on the first unassisted return. EMG was expressed relative to the peak activity recorded during arm flexion after the average activity while sitting in a rest position was subtracted.
Table 1 Summary of the mean movements of the scapula from the rest position to the orientated position for 13 subjects Rotation ( )
Translation (mm)
Mean SD SEM p
Lateral
Ventral
Superior
Upward (coronal plane)
External (transverse plane)
Posterior (sagittal plane)
2.7 10.7 3.0 0.387
2.5 14.8 4.1 0.551
2.6 7.7 2.1 0.254
4.0 3.4 0.9 0.001
3.1 8.4 2.3 0.208
4.0 6.0 1.6 0.029
16
S.L. Mottram et al. / Manual Therapy 14 (2009) 13e18
A
Coronal Plane Sagittal Plane
Coronal plane 30
15 10 5 0
Subjects Fig. 1. The rotation of the scapula in the coronal (upward rotation) and sagittal (posterior tilt) planes between the resting and orientated position is shown. Each pair of bars represents the results of the assisted positioning. For the purpose of this figure the subjects are shown in ascending order of the coronal plane rotation needed.
Rotation during unaided scapula orientation exercise (°)
Rotation in degrees
20
20
10
0
-10 -10
0
10
20
30
Rotation during assisted scapula orientation exercise (°) *
B
*
0.1
0.0
Sagittal plane 30
*
0.2
UT
MT
LT
LD
Fig. 2. Mean EMG level during unaided holding of the scapular orientated position for the first unassisted return to the orientated position. The EMG activity, in excess of that during relaxed sitting, is shown on the y-axis relative to that recorded during an arm elevation, as a proportion of the activity recorded during arm elevation. The means which are significantly different from zero are indicated (*p<0.05). UT, upper trapezius; MT, middle trapezius; LT, lower trapezius; LD, latissimus dorsi.
Rotation during unaided scapula orientation exercise (°)
EMG normalised RMS value
0.3
20
10
0
-10 -10
0
10
20
30
Rotation during assisted scapula orientation exercise (°)
6.3. Scapular orientation learning The movements that occurred during an unassisted return to the orientated position were very similar to those that occurred during the assisted movement (Fig. 3). Each of the three tests of unassisted orientated position is shown as a separate point and it can be seen that the points lie close to the line of identity, which would indicate a perfect reproduction of the movement was demonstrated. The correlation between the assisted and unassisted positions are high (r¼0.919 and 0.944 for the coronal and sagittal planes, respectively). The correlations between the assisted and unassisted positions were also high (above 0.73, p<0.01) for the translations and the horizontal plane rotations even though there
Fig. 3. Comparison of the rotations of the scapula during assisted scapular orientation and unaided return to the orientated in the upper graph A shows the rotations in the coronal plane (upward rotation) and lower graph B shows rotations in the sagittal plane (posterior tilt). There are three trials of return to the orientated position for each subject. The full lines represent the correlation between the datasets while the broken lines are lines of identity.
was no consistent magnitude of movement for these parameters. 7. Discussion The results of this experiment show that normal subjects are able to reproduce the SOE position of the
S.L. Mottram et al. / Manual Therapy 14 (2009) 13e18
scapula within 5 min of being taught. The position was individually determined by taking the mid point of three rotations of the scapula, then employing a range of visual, kinaesthetic and auditory cues in order to facilitate learning. The time scale of position reproduction is especially relevant to physiotherapists treating patients with scapular movement faults as it falls within the usual time available for such teaching. Further, physiotherapists often find it difficult to teach patients the SOE position. It has further significance for physiotherapy educators and mentors teaching novice clinicians who often struggle to teach the SOE. The techniques described here may therefore be useful to physiotherapists seeking to better understand scapular orientation. Further research is needed to determine if subjects with shoulder pain and dysfunction are able to maintain this orientation with the arm by the side both in the immediate and in the long term. The potential for impingement is increased during elevation because the altered scapulo-humeral rhythm may result in the acromion being in closer proximity to the rotator cuff tendons during elevation. The effects of the teaching under loaded conditions and during dynamic/functional movements also need to be addressed. Subjects consistently required upward rotation and posterior tilt in order to reach the SOE position even though the movements required to reach the SOE position were individually determined. Further, the movements required to reach the SOE position are exactly those that are reduced in patients with impingement syndrome and other shoulder dysfunctions (Lukasiewicz et al., 1999; Ludewig and Cook, 2000; Herbert et al., 2002; Lin et al., 2005). Ludewig and Cook (2000) have suggested rehabilitation of shoulder impingement should consider the rehabilitation of upward rotation and posterior tilt of the scapula based on observed movement deficits in symptomatic subjects. Abnormal positioning of the scapula with the arm by the side has also been associated with shoulder pain and pathology. Kibler (1998) described excessive anterior tilt of the shoulder with the arm by the side that can affect the positioning of the scapula, leading to impingement and dysfunction. Additionally, there is evidence that pectoralis minor muscle length, measured with the arm by the side, can influence scapula kinematics and decrease scapula posterior tilting during elevation (Borstad and Ludewig, 2005; Borstad, 2006). The movements used in reaching the SOE position are therefore congruent with the recent findings pertaining to shoulder movement patterns seen in patients with impingement pathology. The activity in four muscles during maintenance of the SOE position was also measured in these normal subjects during the assisted manoeuvre with reference to the amount of activity used to elevate the arm. This showed that all parts of the trapezius were active in
17
maintaining the SOE position while latissimus dorsi was not. Consideration of retraining these muscles may be appropriate in subjects unable to maintain the SOE position. This SOE involves a significant coordinated recruitment of all portions of the trapezius muscle. Johnson et al. (1994) have suggested the role of middle and upper trapezius is to rotate the clavicle about the sterno-clavicular joint. This action will resist downward rotation of the scapula, while mid and lower trapezius may serve to resist anterior tilting. This co-ordinated recruitment may help to maintain optimum orientation. No previous study has measured EMG activity of this exercise so it is not possible to compare results. There are other muscles, which may be involved, e.g. serratus anterior and further research is needed in this area. Ludewig and Cook (2000) and Lin et al. (2005) have described a decrease in serratus anterior muscular activity in subjects with shoulder impingement. There were some limitations of this study that need to be considered when interpreting the results. Firstly, the sample was a small group of normal subjects without pain who may therefore differ from samples of subjects with shoulder pathology. Nonetheless, this study provides a baseline from which future measurements can be interpreted. Secondly, the measurement procedure may be subject to error as the errors in detection of translation and rotation using the CODA system (0.5 mm and 1 , respectively) may have had an impact on the results. Further there is inherent error in the application of skin-mounted markers for scapular movement measurement, although satisfactory for the purposes of this study (Morrissey et al., 2007). Any errors could be assumed to be consistent between assisted and unassisted SOE position reproduction. Finally, there is the possibility that crosstalk between the sections of trapezius measured may have affected the EMG results for the upper and middle fibres of trapezius. Further work needs to establish agreement on the electrode placement for the different parts of trapezius particularly mid.
8. Conclusion The SOE has been defined in normal subjects. This paper demonstrates that it is possible to teach a normal subject to consistently reproduce an unfamiliar movement pattern. The experiment highlights how a trained physiotherapist can influence the position of the scapula in terms of upward rotation and posterior tilting which is believed to be important in the rehabilitation of shoulder dysfunction and control of scapula neutral. All three portions of the trapezius muscle were active whilst maintaining the SOE position. This study has implications for physiotherapists seeking improved understanding of the biomechanics involved in an SOE.
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S.L. Mottram et al. / Manual Therapy 14 (2009) 13e18
Acknowledgement The authors wish to thank the University College London, Institute of Human Performance, Brockley Hill, Stanmore, Middlesex, UK, for the use of the facilities.
References Basmajian JV, DeLuca CJ. Muscles alive-their functions revealed by electromyography. 5th ed. Baltimore: Williams & Wilkins; 1985. p. 273. Borstad JD. Resting position variables at the shoulder: evidence to support a posture-impairment association. Physical Therapy 2006;86:549e57. Borstad JD, Ludewig PM. The effect of long versus short pectorals minor resting length on scapular kinematics in healthy individuals. Journal of Orthopedic and Sports Physical Therapy 2005;35(4):227e38. Cherington M. Accessory nerve: conduction studies. Archives of Neurology 1968;18:708e9. Dickens VA, Williams JL, Bhamra MS. Role of physiotherapy in the treatment of subacromial impingement syndrome: a prospective study. Physiotherapy 2005;91:159e64. Guazzelli FJ, Furlani J, de Freitas V. Electromyographic study of trapezius muscle in free movements of the arm. Electromyography and Clinical Neurophysiology 1991;31:93e8. Herbert LJ, Moffet H, McFadyen BJ, Dionne CE. Scapular behaviour in shoulder impingement syndrome. Archives of Physical and Medical Rehabilitation 2002;83:60e9. Hungerford B, Gilleard W, Hodges P. Evidence of lumbo-pelvic muscle recruitment in the presence of sacro-iliac joint pain. Spine 2003;28(14):1593e600. Jensen C, Vasseljen O, Westgaard R. The influence of electrode position on bipolar surface electromyogram recordings of the
upper trapezius muscle. European Journal of Applied Physiology 1993;67:266e73. Johnson GR, Anderson JM. Measurement of three-dimensional shoulder movement by an electromagnetic sensor. Clinical Biomechanics 1990;5:131e6. Johnson G, Bogduk N, Nowitzke A, House D. Anatomy and actions of the trapezius muscle. Clinical Biomechanics 1994;9:44e50. Karduna AR, McClure PW, Michener LA. Scapular kinematics: effects of altering the Euler angle sequences of rotation. Journal of Biomechanics 2000;33:1063e8. Karduna AR, McClure PW, Michener LA, Sennett B. Dynamic measurements of three-dimensional scapular kinematics: a validation study. Journal of Biomechanics 2001;123:184e90. Kibler WB. The role of the scapula in athletic shoulder function. American Journal of Sports Medicine 1998;26:325e37. Lehman GJ, Lennon D, Tresidder B, Rayfield B, Poschar M. Muscle recruitment patterns during prone leg extension. BMC Musculoskeletal Disorders 2004;5:3. Lin J, Hanten WP, Olson SL, Roddey TS, Soto-quijano DA, Lim HK, et al. Functional activity characteristics of individuals with shoulder dysfunction. Journal of Electromyography and Kinesiology 2005;15:576e86. Ludewig P, Cook TM. Alterations in shoulder kinematics and associated muscle activity in people with symptoms of shoulder impingement. Physical Therapy 2000;80:276e91. Lukasiewicz AC, McClure P, Michener L, Pratt NA, Sennett B. Comparison of 3-dimensional scapular position and orientation between subjects with and without shoulder impingement. Journal of Orthopedic and Sports Physical Therapy 1999;29:574e89. Morrissey D, Woledge RCW, Morrissey MC. Comparison of three dimensional ultrasound and a skin-mounted marker motion tracking system for detecting scapular movement during arm elevation. Journal of Applied Biomechanics 2007, in press. Mottram SL. Dynamic stability of the scapula. Manual Therapy 1997;2:123e31. Mottram SL. Dynamic stability of the scapula. In: Beeton KS, editor. Manual therapy masterclassesdthe peripheral joints. Edinburgh: Churchill Livingstone; 2003. p. 1e17 [chapter 1].
Available online at www.sciencedirect.com
Manual Therapy 14 (2009) 19e27 www.elsevier.com/math
Original article
Sonographic evaluation of the subclavian artery during thoracic outlet syndrome shoulder manoeuvres Claire Stapleton a,*, Lee Herrington b, Keith George a a
Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Henry Cotton Campus, 15-21 Webster Street, Liverpool L3 2ET, UK b Centre for Rehabilitation and Human Performance Research, University of Salford, UK Received 1 November 2006; received in revised form 25 July 2007; accepted 30 July 2007
Abstract Clinical tests for vascular thoracic outlet syndrome (vTOS) generally incorporate shoulder horizontal flexion/extension (HF/HE), abduction (ABD) and external rotation (ER). The effect of these clinical tests on blood flow characteristics and the most effective arm positions for detecting arterial compromise are, however, unknown. The aims of this study are to establish normative vascular responses in the subclavian artery (i.e. arterial diameter [D] and peak systolic blood flow velocity [PSV]) to various arm positions, and determine the incidence of abnormal physiological responses. Ten male and twenty-one female (mean age: 25 yr) healthy volunteers were rigorously screened prior to testing. With the subject seated the arm was passively supported in a randomised series of 12 standardised shoulder positions incorporating varying degrees of HF/HE, ABD and ER. Doppler ultrasound insonated the subclavian artery D (mm) and PSV (cm s1) in each position. Data comparisons were made using ANOVAs with bonferroni adjustment for multiple comparisons. Alpha level was set at p¼0.01. Significant decreases ( p¼0.008) in PSV were recorded from 120 , 90 and 45 ABD (9210, 8911 and 8814 cm s1, respectively) to 180 ABD (mean95% CI: 5216 cm s1). Similarly, post-hoc comparisons revealed a significant decrease ( p¼0.008) in PSV from 120 ABD (9414 cm s1) to 120 ABD with 30 HE and 90 ER (6912 cm s1). Complete lack of blood flow was demonstrated by six subjects and two subjects at end of range ABD and combined end of range ER and HE, respectively. The heterogenous response of asymptomatic individuals with no past history of TOS symptoms raises uncertainty of the validity of positive test responses from extreme arm positions. Clinical decisions based on false positive outcomes have serious implications for mistreatment such as inappropriate surgical intervention; therefore it is imperative that clinical decision is not based on test outcomes alone. Further research is required to determine the cause of heterogenous responses in asymptomatics and discover means to improve test specificity. Ó 2007 Elsevier Ltd. All rights reserved. Keywords: Ultrasonography; Diagnostic tests; Thoracic outlet syndrome
1. Introduction Arterial compromise in the upper extremity has been reported in athletes and non-athletes who perform repetitive overhead throwing actions (Durham et al., 1995; Jackson 2003). A common site of arterial compromise is the subclavian artery (Jackson 2003) and * Corresponding author. E-mail address:
[email protected] (C. Stapleton). 1356-689X/$ - see front matter Ó 2007 Elsevier Ltd. All rights reserved. doi:10.1016/j.math.2007.07.010
compression at either the scalene triangle and/or the costoclavicular space is commonly termed vascular thoracic outlet syndrome (vTOS). Previous research (Longley et al., 1992; Wadhwani et al., 2001; Demondion et al., 2003; Demondion et al., 2006) reports occurrence across a wide age range with a predominance for females over males. The reported incidence of vTOS varies considerably from 4% to over 20% (Harris et al. 1989; Plewa and Delinger 1998; Lee et al. 2006) of patients presenting with thoracic outlet symptoms. Upper limb
20
C. Stapleton et al. / Manual Therapy 14 (2009) 19e27
manoeuvres with or without advanced imaging techniques, such as, computed tomography, magnetic resonance imaging, angiography, and ultrasongography, contribute to the differential diagnosis of vascular and neurogenic causes of thoracic outlet symptoms. Diagnostic upper limb manoeuvres, e.g. Adsons test, Wright’s test, Elevated Arm Stress test, Roos test, selectively incorporate a broad array of shoulder horizontal flexion/extension, abduction and external rotation. It is assumed that these manoeuvres stress the vasculature to accurately reproduce the signs (e.g. radial pulse disappearance) and symptoms (e.g. ischaemic pain, paraesthesia, anaesthesia, heaviness) of vascular compromise. However, diagnostic manoeuvres for vTOS have been shown to produce the signs and symptoms of vascular compromise in asymptomatic as well in symptomatic individuals (Plewa and Delinger, 1998). Plewa and Delinger (1998) concluded that the outcomes of pulse quality and paraesthesia in shoulder manoeuvres were nonspecific for vTOS due to their reproduction with shoulder manoeuvres in healthy asymptomatic subjects. The use of advanced imaging techniques may provide a more objective, accurate and sensitive assessment of vascular compromise. Rohrer et al. (1990) and Demondion et al. (2006) used ultrasound to report clinically significant subclavian stenosis (50% reduction in vessel diameter or 75% reduction in vessel cross-sectional area; Strandness, 2002) in 57% and 14% of subjects with their shoulders placed in abduction, respectively. In addition, Longley et al. (1992) used ultrasound to measure PSV responses to shoulder abduction and reported large heterogeneity with 4 out of 20 control subjects demonstrating clinically significant subclavian arterial narrowing (indicated by a doubling of PSV from baseline; Strandness, 2002). Longley et al.’s reported PSV responses were highly variable and thus considered ineffective for diagnostic criteria. Wadhwani et al. (2001) also reported on PSV of the subclavian artery in healthy and symptomatic individuals with the arm elevated. Averaged results demonstrated a dampened PSV at 180 abduction for the symptomatic group. Unfortunately, the latter two studies display inconsistencies between results reported in tables and text, lack clarity in their asymptomatic/symptomatic subject group designation, and lack statistical power with small sample sizes. Imaging studies to date have used either abduction in isolation or an established diagnostic shoulder manoeuvre as their independent variable. Existing diagnostic shoulder manoeuvres for vTOS are confused by inconsistent descriptions and multiple sites of compression inclusive in the term thoracic outlet syndrome. Uniquely, the present study seeks to extend our knowledge of subclavian artery stenosis by evaluating the haemodynamics in a range of different arm positions. No previous studies have broken down standard diagnostic
tests used in clinical practice for diagnosis of upper limb vascular pathology and examined, using imaging techniques, the vascular response to the individual movement components. It is hoped that these comparisons will determine the value of each movement in the differential diagnosis of vTOS. Therefore, the aims of this study are to: establish normative vascular responses (i.e. arterial diameter [D], peak systolic velocity [PSV] of the subclavian artery, and radial artery blood pressure) in young healthy asymptomatic subjects to various arm positions; and to determine the incidence of clinically significant arterial stenosis as defined by Strandness (2002).
2. Methods 2.1. Subjects Forty-one healthy males and females between the ages of 18 and 40 years old were recruited via local advertisement in the University. Following verbal and written experimental briefing, subjects provided written consent to participation. Local ethical approval was granted by Liverpool John Moores Ethics Committee. Subjects were screened subjectively to exclude those with symptoms or conditions related to upper limb vascular or neurogenic compression syndromes (i.e. paraesthesia, anaesthesia, heaviness, coldness), or any other condition or musculo-skeletal injury likely to be exacerbated by the testing procedure. Exclusions included previous shoulder surgery, glenohumeral joint dislocations and/or subluxations, fractures to the humerus, clavicle and 1st through to 3rd ribs, inflammatory joint conditions, vascular or neurological disorders, or past or present injury to the neck, shoulder and upper limb. A chartered physiotherapist performed the objective assessment to screen for musculoskeletal conditions likely to elicit symptoms throughout the testing procedure. This consisted of active range of motion with overpressure for cervical, thoracic, scapulo-thoracic and glenohumeral range of movements. Two subjects were excluded through screening and a further 8 were excluded due to poor clarity of the ultrasound image. Twenty-one female and ten male subjects with a cohort age range of 19e35 yr (meanSD: 254 yr) were included in the final analysis. 2.2. Subject position and standardisation Following ten minutes seated rest the subject had their right upper limb supported on a purpose built adaptable arm-rest. Anatomical landmarks were identified to aid consistent reproduction of abduction. With the upper limb passively supported at approximately 45 abduction the axis of the goniometer was placed
C. Stapleton et al. / Manual Therapy 14 (2009) 19e27
over the posterior corner of the acromion with the static arm parallel to the spine and the moving arm placed over the line between the axis and the mid-point between medial and lateral epicondyles. For each subject the height of the arm-rest was adjusted and marked to indicate 90 abduction and 120 abduction. To determine 180 abduction the upper limb was secured to the back board of the apparatus with the humerus as close to the ear as possible. Throughout testing, blocks were secured to the armrest to maintain the desired degree of shoulder girdle horizontal extension/flexion and glenohumeral external rotation. To control for the effect of compression at the scalene triangle subjects were instructed to maintain an upright posture with the head in a neutral position, therefore altered blood flow detected could be assumed to be associated with the structures bounding the costoclavicular space. A large belt was secured around the subjects’ thorax and the apparatus, and a visual marker at eye level was provided to stabilise upper body position (see Fig. 1). After movement positions were determined subjects were assessed in 12 arm positions (see Table 1) that were presented in a random order (computer generated). A rest period of 2 min (or until any signs and symptoms of altered haemodynamics had resolved) was provided between testing for each arm position. 2.3. Data acquisition After 30 s in each position a songraphic exam was performed in a consistent manner using a portable ultrasound scanner (ESOATE MyLab30cv) with
21
a 10e15 MHz multi-linear array ultrasound transducer. The transducer was positioned beneath the clavicle with parasagittal orientation to locate the subclavian artery as it emerges from the costoclavicular space. For each arm position B-mode imaging aided by colour flow mapping detected the vessel and an optimal longitudinal view was recorded. The split-screen facility allowed the real-time B-mode longitudinal vessel image to remain on screen while acquiring the Doppler spectral waveform. An average PSV value (cm s1) was determined from 3 to 5 consecutive cardiac cycles of the spectral Doppler waveform. An ECG trace was visible on-screen throughout testing allowing the vessel diameter to be captured at end-diastole indicated by the peak of the ECG R wave. The subclavian artery diameter (mm) was measured offline at a later date using electronic callipers. The same trained sonographer performed all scans and data analysis to eliminate intra-observer error. Coefficients of variation for this sonographer making these assessments were determined in pilot work as 22% and 18% for PSV and diameter measurements, respectively. The sonographer was blinded to subject identity and arm position for all sonographic image analyses. An automated radial artery blood pressure cuff (DINAMAP Pro 100V2, GE medical systems, Tampa, USA) recorded systolic blood pressure at each arm position at the end of the songraphic data collection. After the completion of each sonographic data collection subjects were questioned after each test position to determine the presence of any pain, pins and needles, numbness, heaviness or other sensations.
Fig. 1. Subject positioning for baseline position (A) and position 12 (B). (C) illustrates the use of a block to maintain 90 external rotation.
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C. Stapleton et al. / Manual Therapy 14 (2009) 19e27
Table 1 Description of arm positions and groupings for statistical comparisons for subclavian artery peak systolic velocity, diameter and systolic blood pressure APN
1 2 3 4 5 6 7 8 9 10 11 12
Arm position description
Approximately 45 abduction 90 abduction 120 abduction 180 abduction 90 abduction, 30 horizontal flexion 90 abduction, 30 horizontal flexion, 90 external rotation 90 abduction, 30 horizontal extension 90 abduction, 30 horizontal extension, 90 external rotation 120 abduction, 30 horizontal flexion 120 abduction, 30 horizontal flexion, 90 external rotation 120 abduction 30 horizontal extension 120 abduction, 30 horizontal extension, 90 external rotation
Comparison group A
B
C
D
E
F
G
H
I
U U U U
U U
U U
U
U
U U
U U
U
U
U
U
U
U
U U
U U U U
U U U U
U U U U
U U
APN, arm position number.
2.4. Data analysis In order to simulate diagnostic manoeuvres and the manner of their use in clinical practice the data were grouped to allow comparison of arm positions progressively increasing either in range or in the combination of movements incorporated (see Table 1). Comparison group A allowed the effects of abduction to be analysed in isolation. The contribution of external rotation and horizontal flexion/extension were analysed within comparison groups B to E and F to I, respectively. Standard deviation, KolmogoroweSmirnov, and skewness and kurtosis were calculated for each data set and determined the use of parametric or non-parametric tests. Where data met parametric assumptions one way repeated measures ANOVA was used. All analysis of variance calculations included post-hoc comparisons with Bonferroni correction. Data groups not meeting the criteria for normality of distribution were subject to transformation (the type, e.g. log and square root, indicated by the shape of the distribution curve; Tabachnick and Fidell, 1996). Data sets failing transformation employed the non-parametric Friedman’s test. The alpha level was set at 0.01 to reduce the risk of type I error prevalent with multiple analyses on the same sample. Independent t-tests were conducted on individuals reporting symptoms and those who were symptom-free for each outcome variable.
3. Results 3.1. Missing data No data were available for two subjects at 180 abduction (position 4); for one the position was too
uncomfortable to be maintained, for the second case the subclavian artery could not be located due to a combination of the location of the vessel underneath the clavicle and the relative depth of the artery due to the thickness of the pectoralis muscles in this position. 3.2. Peak systolic velocity Data for most arm positions were consistent with no change in subclavian artery PSV (see Table 2). However, significant ( p<0.01) differences were observed for comparison group C and G (see Table 3). Wilcoxon t-tests and post-hoc comparisons with Bonferroni adjustment revealed, in both comparisons a significant decrease in PSV at position 8 (90 abduction, 30 horizontal extension and 90 external rotation) compared to position 2 (90 abduction) and position 1 (45 abduction). In addition, a significant decrease in mean PSV was detected between arm positions in comparison group A (see Table 3). Post-hoc comparisons indicated the mean PSV for position 4 (180 abduction) was significantly lower than positions 3, 2 and 1 (120 , 90 and 45 abduction, respectively). Similarly, significant differences were identified in comparison groups I and E with both post-hoc comparisons revealing a significant decrease in mean PSV from position 3 (120 abduction) to position 12 (120 abduction with 30 horizontal extension and 90 external rotation). These differences are equal to or above the previously calculated coefficient of variation of 22%. The mean decrease in PSV at position 4 (180 abduction) and position 12 (120 abduction with 30 horizontal extension and 90 external rotation) was associated with a heterogenous PSV response between individuals. Specifically, lack of blood flow was demonstrated by six
50.12.9
779
42 (13)
50.93.6
974
19 (6)
50.12.8
787
29 (9)
52.52.7
995
10 (3)
subjects (position 4) and two subjects (position 12), respectively. This was illustrated by smaller monophasic waveforms, or widened and distorted waveforms (spectral broadening) both representative of proximal narrowing. Fig. 2B gives an example of a dampened monphasic waveform. 3.3. Diameter Table 2 presents the mean diameter for the subclavian artery at each arm position. No significant differences were demonstrated between vessel diameter measurements across different arm positions (meanSD: 509 mm). No evidence of total vessel occlusion was seen in the visible longitudinal scans recorded, despite alteration in PSV recordings.
23 (7) 7 (2)
Group mean data for systolic blood pressure mirrored that of PSV (see Table 2). However, significant reductions in mean systolic blood pressure from baseline were recorded for all positions incorporating at least 120 abduction and/or 90 external rotation (see Table 4). Arm positions incorporating external rotation demonstrated significant reductions in mean systolic blood pressure compared to the corresponding position with no external rotation; however, most counterpart arm positions differing only in horizontal flexion/extension showed no significant differences (see Table 4). Again, in these positions the normative response was heterogenous. This was partly due to undetectable systolic blood pressure for 19% (six subjects), 7% (two) and 6% (two) of subjects in positions 4, 8 and 12, respectively. 3.5. Symptomatic versus asymptomatic reporting
PSV, peak systolic velocity; CI, confidence interval.
7 (2) 7 (2) 0 (0)
13 (4)
52 (16)
13 (4)
8810 1104 917 1154 5711 1083 1204
935
51.03.3 48.83.8 49.33.5
50.83.3
50.64.1
49.83.8
50.33.0
50.13.0
68.912.2 88.015.2 73.99.1 89.713.8 87.110.2 89.010.9
Mean PSV (cm s1) Mean diameter (mm) Systolic BP (mmHg) Symptom reporting % (n)
88.410.4
92.414.2
52.016.0
85.310.0
84.58.2
70.311.2
12 11 10 9 8 7 6 5 4 2
3
23
3.4. Systolic blood pressure
1 Arm position
Table 2 Mean subclavian artery PSV (cm s1)95% CI and diameter (mm)95% CI readings, and percentage (number) of subjects reporting symptoms, for each arm position
C. Stapleton et al. / Manual Therapy 14 (2009) 19e27
Although asymptomatic healthy subjects were investigated, many reported sensations such as paraesthesia, anaesthesia, coldness, heaviness and achy pain in specific test positions. The highest rate of symptom reporting (52% and 42%) were recorded for position 4 and 12, respectively. To a lesser extent other arm positions also elicited some symptoms in some individuals (see Table 2). No significant differences in mean PSV, vessel diameter or blood pressure were detected between symptom-free and symptom-reporting individuals in each test position.
4. Discussion The unique data from the present study is that arm positions incorporating the extreme of abduction or a lesser degree of abduction with combined end of range
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C. Stapleton et al. / Manual Therapy 14 (2009) 19e27
Table 3 Significant statistics for PSV data: group comparisons with post-hoc analysis (or non-parametric alternative) Comparison group
APN
Statistical test
Significance
APN pairwise comparisons
Mean difference (cm s1)
Significance
A
1 2 3 4
Anova F3,26¼9.39
p<0.0001
1v4 2v4 3v4
36.41 36.95 40.36
p<0.001 p<0.001 p<0.001
C
1 2 7 8
Friedman c23;31 ¼ 23:12
p<0.0005
Wilcoxon tests 1v8 2v8
Z¼3.58 Z¼4.174
p<0.0005 p<0.0005
E
1 3 11 12
Anova F3,28¼4.55
p¼0.01
1 v 12 3 v 12
21.95 25.23
p¼0.008 p¼0.008
G
1 2 6 8
Anova F3,28¼9.42
p<0.0005
1v8 2v8
20.56 19.45
p¼0.001 p<0.0005
I
1 3 10 12
Anova F3,28¼5.55
p¼0.004
1 v 12 3 v 12
21.95 25.23
p¼0.008 p¼0.008
APN, arm position number; PSV, peak systolic velocity.
horizontal extension and external rotation results in a heterogenous response for PSV, systolic BP and presence of symptoms in subjects rigorously screened for an absence of vTOS. Specifically at the extreme of abduction, 19% demonstrated undetectable blood flow or blood pressure, 32% demonstrated a dampened (70% reduction) PSV response and 52% of subjects reported symptoms. As with previous findings (Rohrer et al., 1990; Longley et al., 1992; Plewa and Delinger, 1998; Demondion et al., 2006) the results of the present study are consistent with high incidences of abnormal physiological responses for vTOS diagnostic shoulder manoeuvres in healthy subjects. Interestingly, Longley et al. (1992) reported a doubling of PSV in some subjects. Where PSV is measured at the site of significant arterial narrowing the characteristic outcome is an increased or doubled peak systolic velocity. However, the present study found no subjects with a doubled PSV at 180 abduction, but 32% demonstrated at least a 70% reduction in PSV compared to values recorded at baseline, with 19% having no detectable blood flow. The reason for these differences lies in the location of the transducer in relation to the stenosis. In the present study the transducer was located distal to the site of compression. Typically flow disturbances distal to the site of significant narrowing are characterised by a dampened PSV and spectral broadening. This point is demonstrated with
PSV readings of 19% indicating a complete vessel occlusion but with no comparable significant differences recorded for the subclavian artery diameter. Consistent with Rohrer et al. (1990), significant reductions in systolic blood pressure were recorded in positions incorporating end of range abduction and combined end of range horizontal extension and external rotation. As blood flows through a significantly narrowed arterial segment, blood pressure rises, but distal to the stenotic segment, where the diameter is restored and blood flow velocity reduced, the pressure drops. This, in addition to the drop in blood pressure associated with the orthostatic effects of arm elevation, explains the reduced and undetectable systolic blood pressure observed in the present study. The proximal stenosis indicated by the significantly reduced or undetectable PSV and systolic BP is likely attributable to the compression of the subclavian artery at the costoclavicuar space. During arm elevation the clavicle performs a scissor-like action on the first rib reducing the dimensions of the costoclavicular space. The addition of horizontal extension produces retraction at the scapulothoracic joint which acts to pull the distal end of the clavicle towards the 1st rib reducing the dimensions of the costoclavicular space further. Although the present study’s results suggest that gleno-humeral external rotation is a significant contributor to altered PSV at the subclavian artery, it is more difficult to
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C. Stapleton et al. / Manual Therapy 14 (2009) 19e27
Fig. 2. The subclavian artery in its long axis pictured by B-mode ultrasound and underneath the spectral waveform captured via pulsed Doppler ultrasound at baseline (A) and 180 abduction (position 4) (B). The images were from the same subject.
reason how pure gleno-humeral rotation results in anatomical compression specific to the costoclavicular space. It is thought that this movement is not isolated to the gleno-humeral joint during external rotation and the scapula and clavicle are simultaneously pulled backward having the same consequences as horizontal extension. Alternatively, compression at distal sites inflicts turbulent blood flow proximally. For example, pectoralis major and minor muscles become taut with external rotation and the humeral head translates anteriorly both having the potential to cause compression to the adjacent axillary artery (Dijkstra and Westra, 1978; Vlychou et al., 2001). The cause of the heterogenous repsonse for PSV, systolic BP and the presence of symptoms are uncertain. Possible theories involve anatomical abnormalities, altered movement patterns due to posture or hyper/hypomobile joints, concurrent neural or vascular compression resulting in a double-crush type phenomenon, vascular tone, cardiovascular health and lower pain tolerance. Clinically, the majority of physiotherapists do not have access to advanced imaging equipment; therefore diagnosis relies upon the clinical presentation, subjective history and physical examination. Specific upper limb manoeuvres use the reproduction of symptoms and the subjective report of radial pulse strength as key indicators of a positive test result. Consistent with Plewa and Delinger (1998) the present study found a high proportion of healthy subjects reporting symptoms. Interestingly, in the present study the percentage of subjects reporting symptoms far outweighs the percentage with reduced blood flow characteristics. It is likely that a proportion of subjects expressing symptoms were a result of compression of other structures. Accompanying the subclavian artery throughout its course is the brachial plexus and the subclavian vein. Compression at any of the anatomical sites
Table 4 Statistics for systolic BP data APN comparisons
Non-parametric Wilcoxon test/parametric pair wise comparisons
Significance
Abduction
1v3 2v3 3v4
Z¼4.86 Z¼4.67 Z¼4.84
p<0.0005 p<0.0005 p<0.0005
External rotation
5v6 7v8 9 v 10 11 v 12
Z¼4.84 Z¼4.69 Z¼4.55 Z¼4.78
p<0.0005 p<0.0005 p<0.0005 p<0.0005
Horizontal extension
5v7 6v8 9 v 11 10 v 12
MD¼4.58 Z¼0.454 MD¼2.45 Z¼0.029
p¼0.006 p¼0.650 p¼1.000 p¼0.977
APN, arm position number, MD, mean difference (mmHg).
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C. Stapleton et al. / Manual Therapy 14 (2009) 19e27
(scalene triangle, costoclavicular space, sub-coracoid space, anterior to humeral head) could result in compression of anyone of these structures with the resultant production of symptoms. These results indirectly infer that shoulder manoeuvres for vTOS are not specific to arterial causes. Although clinically, obliteration of the radial pulse or undetectable blood pressure aids the diagnosis of arterial involvement it does not specify the site of compression or exclude concurrent nerve or vein compression. In fact, any clinical test reliant on the production of symptoms that also incorporates abduction and combined horizontal extension and external rotation, for example, the upper limb tension test (ULTT), should consider neural, venous and arterial structures as the source. The lack of significance between positions 7 and 8, 11 and 12, 6 and 8, and 10 and 12 suggests that both external rotation and horizontal extension in combination are required to elicit changes to blood flow characteristics. The results for positions 4, 8 and 12 suggest adequate stress is placed on the vasculature to elicit measurable changes to blood flow velocity. However, where positions 4 and 12 demonstrated clinically significant signs of reduced peak systolic velocity (demonstrated by an altered waveformdsee Fig. 2B) in a small proportion of subjects (19% (six subjects) and 7% (two subjects), respectively), position 8 (90 abduction, 30 horizontal extension and 90 external rotation) did not. Position 8 may therefore possess greater specificity and have the potential to be the most beneficial arm position for diagnostic purposes; however, without additional investigations for sensitivity a definitive judgment cannot be made. The present study is not without limitations. It would have been preferable to image the subclavian artery both supra- and sub-clavicularly. This would better localise any observed effects to the costoclavicular space; unfortunately with the arm at 180 abduction, the supraclavicular fossa would not accommodate the transducer. In addition, due to movement of the artery with arm elevation, it is questionable whether the identical arterial segment would be re-imaged in each trial. The calculated coefficient of variation of 22% is high and is thought to reflect the physiological variability of this measure. For the purpose of this study this level of reliability is acceptable as the difference reported for PSV between arm positions was greater than 22% and therefore meaningful. As well as achieving a greater understanding of the mechanisms behind altered PSV and systolic BP with external rotation, further research is required to ascertain all factors contributing to vTOS. Investigating the cause of abnormal physiological responses and heterogenous responses in asymptomatic subjects, for example, discovering the relationship between such factors as, posture, hyper/hypomobility, vascular tone, cardiovascular health, pain sensitivity and diagnostic outcome,
would highlight other predisposing factors and aid the development of diagnostic criteria high in specificity. In addition, the incidence, etiology and diagnosis of other sites of arterial compression inclusive in the term vTOS (e.g. scalene triangle, sub-coracoid space and anterior to the humeral head) warrant further investigation. In conclusion, vascular parameters were largely unaffected by arm movements in normal healthy adults. Only at the extremes of range of motion were significant alterations recorded in PSV, systolic BP and presence of symptoms. The group mean response also masks the heterogenous vascular responses at the extremes of range of motion. These findings support the reports of high incidences of abnormal physiological responses for vTOS with some shoulder manoeuvres, highlighting the lack of differential diagnostic power, and the need to integrate all information gained from a clinical assessment.
References Demondion X, Bacqueville E, Paul C, Duquesnoy B, Hachulla E, Cotten A. Thoracic outlet: assessment with MR imaging in asymptomatic and symptomatic populations. Radiology 2003;227(2):461e8. Demondion X, Vidal C, Herbinet P, Gautier C, Duquesnoy B, Cotten A. Ultrasonographic assessment of arterial cross-sectional area in the thoracic outlet on postural maneuvers measured with power Doppler ultrasonography in both asymptomatic and symptomatic populations. Journal of Ultrasound in Medicine 2006;25(2):217e24. Dijkstra PF, Westra D. Angiographic features of compression of the axillary artery by the musculus pectoralis minor and the head of the humerus in the thoracic outlet compression syndrome. Case report. Radiologia Clinica 1978;47(6):423e7. Durham JR, Yao JS, Pearce WH, Nuber GM, McCarthy 3rd WJ. Arterial injuries in the thoracic outlet syndrome. Journal of Vascular Surgery 1995;21(1):57e69. Harris J, Huang W, Tyrer P, Burnett A, May J. Clinical and photoplethysmographic assessment of thoracic outlet arterial compression. The Journal of Vascular Technology 1989; 13(20e23). Jackson MR. Upper extremity arterial injuries in athletes. Seminars in Vascular Surgery 2003;16(3):232e9. Lee AD, Agarwal S, Sadhu D. Doppler Adson’s test: predictor of outcome of surgery in non-specific thoracic outlet syndrome. World Journal of Surgery 2006;30(3):291e2. Longley D, Yedlicka J, Molina E, Schwabacher S, Hunter D, Letourneau J. Thoracic outlet syndrome: evaluation of the subclavian vessels by color duplex sonography. American Journal of Roentgenology 1992;158(3):623e30. Plewa MC, Delinger M. The false-positive rate of thoracic outlet syndrome shoulder maneuvers in healthy subjects. Academic Emergency Medicine 1998;5(4):337e42. Rohrer MJ, Cardullo PA, Pappas AM, Phillips DA, Wheeler HB. Axillary artery compression and thrombosis in throwing athletes. Journal of Vascular Surgery 1990;11(6):761e8. Strandness D. Hemodynamics of arterial stenosis and occlusion. In: Strandness D, editors. Duplex scanning in vascular disorders, 3rd ed. Lippincott Williams and Wilkins; 2002. p. 68 [chapter 4].
C. Stapleton et al. / Manual Therapy 14 (2009) 19e27 Tabachnick B, Fidell L. Normality, linearity, and homoscedasticity. In: Tabachnick B, Fidell L, editors. Using multivariate statistics. 4th ed. New York: HarperCollins; 1996. chapter 4, p. 82. Vlychou M, Spanomichos G, Chatziioannou A, Georganas M, Zavras G M. Embolisation of a traumatic aneurysm of the posterior
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circumflex humeral artery in a volleyball player. British Journal of Sports Medicine 2001;35(2):136e7. Wadhwani R, Chaubal N, Sukthankar R, Shroff M, Agarwala S. Color Doppler and duplex sonography in 5 patients with thoracic outlet syndrome. Journal of Ultrasound in Medicine 2001;20(7):795e801.
Available online at www.sciencedirect.com
Manual Therapy 14 (2009) 28e35 www.elsevier.com/math
Original article
Posteroanterior movements in tender and less tender locations of the cervical spine Neil Tuttle*, Rod Barrett, Liisa Laakso School of Physiotherapy and Exercise Science, Griffith University, Gold Coast, Qld 9726, Australia Received 4 January 2007; received in revised form 18 June 2007; accepted 13 September 2007
Abstract In order to determine how posteroanterior movements (PAs) are related to tenderness and thus possibly symptom production, we measured PA movements to a force of 25 N on each side of the cervical spines of asymptomatic subjects. From 10 subjects (six females and four males; mean age 37.2, range 21e50), 10 locations with a difference in tenderness to pressure between sides were used for analysis. The forceedisplacement and stiffnesseforce curves for tender and control sides were compared in four ways: simultaneous confidence bands (SCBs) for each side; width of SCBs for each side; SCBs of the difference between pairs of the tender and control curves; and simultaneous prediction bands (SPBs) from the tender side were compared to individual curves of the controls. The tender side demonstrated greater variation of both displacement and stiffness. The tender sides demonstrated greater within-subject stiffness for all force levels above 12 N. All individual stiffnesseforce curves of the tender sides were significantly different from the control side. Expected differences in single measures of either displacement or stiffness were not detected. The results suggest that the pattern of stiffness is a more effective method of characterizing PA mobility than single measures used in previous studies. Ó 2007 Elsevier Ltd. All rights reserved. Keywords: Range of motion; Articular; Physical therapy techniques; Manipulation; Spinal
1. Introduction Musculoskeletal symptoms such as neck or back pain are amongst the most common reasons patients seek medical attention (Bogduk et al., 2003). Dysfunction of movement between individual intervertebral motion segments is considered to be a potential source of spinal musculoskeletal symptoms (Banks, 1998) and passive movement tests such as spinal posteroanterior movements (PAs) are intended to localize and assess the dysfunctional intervertebral movement (Maitland et al., 2005). Although many authors advocate motion palpation as an important component of physical examination * Corresponding author. Tel.: þ61 7 55528930; fax: þ61 7 55528674. E-mail address: n.tuttle@griffith.edu.au (N. Tuttle). 1356-689X/$ - see front matter Ó 2007 Elsevier Ltd. All rights reserved. doi:10.1016/j.math.2007.09.003
(Bullock-Saxton et al., 2002), the usefulness of passive movement tests such as spinal PAs has been brought into question by inconsistent repeatability (Smedmark et al., 2000; Pool et al., 2004). In spite of a lack of repeatability, manual assessment of passive movement has been shown to be useful clinically. For example, symptomatic locations (Jull et al., 1988) and the location of congenital fusion have been reliably detected by manual motion palpation (Humphreys et al., 2004). In a clinical study, the lumbar spines of patients were classified by findings on manual palpation as hypomobile or hypermobile. Patients who received corresponding treatment (manipulation to increase segmental mobility for the hypomobile group and stabilization exercises to counteract excessive mobility for the hypermobile group) had better treatment outcomes than those receiving randomly allocated treatment (Fritz et al., 2005).
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Spinal PAs were previously thought to produce isolated movement between a target pair of vertebrae and the response felt by the therapist was considered to be a direct indicator of the local intervertebral movement (Grieve, 1981). It is now clear from both in vivo (Lee and Evans, 1997; Caling and Lee, 2001; Kulig et al., 2004; Lee et al., 2005) and in vitro (Gal et al., 1997; Sran et al., 2005) studies that in addition to moving the target intervertebral segment, spinal PAs also move other structures including a number of intervertebral levels as well as extra-spinal structures. In order to clarify the usefulness of spinal PAs, a number of investigators developed instrumented methods to objectively assess PA movements. Interpretation of data from studies discussed in a recent review (Shirley, 2004) relied on single scalar values of displacement or stiffness extracted from the forceedisplacement (FD) curves of spinal PAs to characterize the stiffness of the entire movement. Using these single values to assess stiffness, instrumented measures of spinal PAs have been successful in detecting differences occurring with segmental dysfunction. For example, differences have been demonstrated with reduction in symptoms in patients with low back pain (Latimer et al., 1996b), artificially induced disc degeneration in a porcine model (Kawchuk et al., 2001), and local intervertebral stiffness in vitro in human thoracic spines (Sran et al., 2005). Using the same criteria for assessing stiffness, differences have been found also in relation to a wide variety of factors whose influence is extraneous to local intervertebral mobility (Kawchuk and Fauvel, 2001) including subject position (Edmondston et al., 1998; Chansirinukor et al., 2001), stage of respiration (Shirley et al., 2003), size of the indentor (Squires et al., 2001), and muscle contraction (Hodges et al., 2003; Colloca and Keller, 2004). The methodologies used in these studies are able to detect altered stiffness of spinal PAs resulting from a variety of structures, but are unable to differentiate between alterations resulting from the targeted intervertebral segment and those resulting from extraneous factors. We therefore set out to identify particular patterns of spinal PA stiffness associated specifically with intervertebral dysfunction (as indicated by local tenderness to pressure) using a protocol similar to that recommended for manual assessment of unilateral PAs (Maitland et al., 2005). That is, we compared PA movements at tender and less tender locations that would otherwise be expected to be as similar as possible; i.e. side-toside at the same spinal level. Rather than relying on single values of stiffness or displacement, we compared the patterns of displacement and stiffness throughout the PA movement using a bootstrapping method of calculating simultaneous confidence bands (SCBs) and simultaneous prediction bands (SPBs) to detect more specific differences. We hypothesized that, in addition to reduced displacement and an increase in single
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values of PA stiffness, more specific differences in the patterns of stiffness throughout the PA movement would correspond to differences in local tenderness to pressure. By understanding the specific characteristics of PA stiffness related to tenderness (and presumably intervertebral dysfunction), we hope to enable more accurate interpretation of manual and instrumented assessment of PA movements.
2. Methods 2.1. Subjects and experimental design Asymptomatic subjects were recruited from university staff and students. Asymptomatic subjects were defined as participants with an absence of current neck symptoms, symptoms within the past 6 months that required treatment or contraindications or precautions to manual therapy treatment. Asymptomatic subjects as defined above are known to have a significant incidence of low-level symptoms (Lee et al., 2004). As tenderness to PA movements is considered to be an indicator of symptoms, it was expected that PAs to the cervical spine in this population would be tender to pressure at some locations. Ten subjects (six females and four males; mean age 37.2 years, range 21e50 years; mean weight 72.7 kg, range 52e92 kg; mean height 169.9, range 155e 179 cm) were recruited for the study. The experimental protocol was approved by the Griffith University Human Research Ethics Committee and all individuals provided written confirmation of their informed consent prior to participation. Each subject participated in one session consisting of two trials. The procedures were explained and the subjects were familiarized with the equipment and operation of the pain indicator prior to the first trial. The subjects were instructed that they might experience some pressure pain during the procedures, but they could tell the operator to stop the trial at any time. For each trial, the subjects were prone on a standard treatment bed modified to ensure a reproducible position and on which the Passive Movement Assessment Device (PMAD) was mounted. Each trial consisted of the application of a unilateral PA force to a total of six locations: the right and left side at each of three levels separated by 12 mm. It is not possible to accurately locate specific anatomical levels without medical imaging so the three levels were repeatable positions in the mid cervical region that could be accessed by the PMAD (the therapist considered the highest level assessed for any subject to correspond to C2 and the lowest to C6). After the first trial, the subject stood and walked a few steps before the second trial.
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The assessment at each location consisted of five applications of force up to 25 N performed at a frequency of approximately 1 Hz which is within the range used in manual assessment of intervertebral movement (Snodgrass et al., 2006). The subject rated the maximum intensity of pressure pain experienced during any of the five repetitions and the operator was blind to their response. A single qualified Musculoskeletal Physiotherapist with over 30 years experience performed both trials.
The pain indicator was a linear array of 20 LEDs located under the bed not visible to the operator, but visible to the subject in the test position. The subject indicated the level of pain with the LEDs acting as a visual analogue scale. No LEDs represented no pain and all LEDs representing the worst pain imaginable. Data collection, storage and operator feedback (an audible sound when the maximum force of 25 N was reached) were performed with custom software written in Labview Version 7.1 (National Instruments).
2.2. Instrumentation and data collection protocol 2.3. Data and statistical analysis The PMAD (Fig. 1) was designed to be capable of assessing unilateral PAs of the cervical spine in a manner as similar as possible to manual palpation. The PMAD consisted of an instrument for measuring the force and displacement that occurred when an indentor was applied to the subject. The indentor was a 25 mm length of 12 mm square aluminium section with edges rounded to a radius of approximately 1 mm. The operator applied a force through a thumb-hold above the indentor. A linear potentiometer (Hollywell LTS04N04KB5C) measured the displacement and a load cell (Transducer Technologies MLP-25) mounted between the thumbhold and the indentor measured the force. The device was adjusted such that the medial edge of the indentor contacted the patient 5e15 mm from the midline and the movement was directed 10 medially from the vertical. The sensors were connected to a PC through a USB DAQ card (NI 40006, National Instruments) and data were sampled at 100 Hz. The assembly could be fixed at 12 mm intervals along the long axis of the bed and be repositioned easily to a corresponding position on the contralateral side. A more complete description of the instrumentation and data collection protocol is described in our previous work along with repeatability data for the device (Tuttle et al., 2007).
Fig. 1. Passive Movement Assessment Device (PMAD).
Data from test locations were used for further analysis if a difference in the pain rating of at least two LEDs (equivalent to 1 point on a 10-point scale) was found to occur between sides at the same level during the same trial. In the event that both trials of the same location had a difference of greater than two LEDs, only the one with the greatest difference was used in further analysis. A total of 10 pairs of locations from six subjects fulfilled the criteria and were used for further analysis. The median pain level on the tender side was 5.5 points (range 2.5e8.5) and for the less tender control side was 3.0 points (range 1.5e5.5). Following data collection, the force and displacement data were processed with customized software using Matlab Version 7.04 (Mathworks Inc.). Force and displacement values for each trial and each location were filtered using a second-order low-pass Butterworth filter with a cut-off frequency of 2.5 Hz. The displacement at 0.5 N was assigned a value of zero to create a common origin for all curves and a single average curve was calculated for each test location. Displacement and stiffness values were extracted from the curves for 100 data points at 0.25 N intervals from 0.5 to 25 N of force (Tuttle et al., 2007). Specialized methods of statistical analysis for assessing continuous (time series) data have been used in gait analysis but to our knowledge have not been applied previously to the assessment of passive movement. A detailed description of the type of analysis used in this study can be found in Lenhoff et al. (1999) and the application to the current study is described more fully in the Appendix. Briefly bootstrap resampling with PopTools (Hood, 2005) was used to calculate SCBs and SPBs. SCBs define the band within which the entire mean curve of a group can be expected to lie while SPBs define the band which would be expected to fully enclose the entire length of a given proportion of individual curves from the population. As it was not known beforehand how differences in spinal PAs between the tender and control sides might affect the FD or stiffnesseforce (SF) curves, four methods were used to compare the two sides for both types of curves. Firstly, the 95% SCBs were calculated for both the tender
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and control sides. Portions of the curves were considered to be significantly different when the SCBs for the tender and control sides did not overlap. Secondly, the 95% confidence intervals of the widths of the SCBs of the tender and control sides were compared to assess for differences in variability between sides. Thirdly, SCBs were calculated for the differences between the tender and control sides and where the bands did not contain zero, the result indicated a significant difference. Finally, the individual FD and SF curves from the tender sides were overlaid on the SPBs for the control side. Portions of the individual curves outside of the SPBs indicated the portion of the curve that was significantly different from the curves of the control side.
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curves demonstrating that no significant differences were detected between the means of either displacement or stiffness for the two sides at any level of force. The mean width of the SCB of the FD curves from the tender sides was wider than the control sides by 2.00 mm (CI¼1.90e2.12) and of the SF curves by 0.52 N/mm (CI¼0.44e0.60) demonstrating that there was greater variability of both displacement and stiffness on the tender sides. Fig. 3c shows the SCBs of the difference in displacement (tender minus control) between the two sides for each level of force. The bands contain zero for all force values indicating the differences were not significant. Fig. 3d shows that the difference in stiffness between the two sides was significant for all forces above 12 N.
3. Results 3.1. Representative data The FD and SF curves for tender and control sides from two representative locations are shown in Fig. 2a and b, respectively. Although it could be considered to be the independent variable in this study, force is represented on the Y-axis of Fig. 2a as is the convention for FD curves. The FD curves from the two subjects did not demonstrate consistent differences between the tender and control sides. The SF curves in Fig. 2b show comparisons of the stiffness data for tender and control sides with the independent variable (force) on the X-axis. The SF curves from the two tender sides shown in Fig. 2b each have characteristic portions that diverge from the control curves when the applied forces are in the mid and upper range of forces used in the current study.
3.3. Comparisons of individual tender curves to control side SPBs were plotted to determine if specific areas of individual curves of the tender sides differed from the control side. Fig. 3e shows that 6 out of the 10 FD curves from the tender sides extended outside of the SPBs for the control sides indicating significant differences from the control sides. There did not appear to be a consistent pattern to the differences as four curves demonstrated less displacement throughout the force range, one less displacement in the latter half and one more displacement in the early half. In Fig. 3f, all of the SF curves from tender locations extended outside the SPB of the control sides indicating that all of the tender curves were significantly different from the control side. Eight of the tender curves were stiffer either between 12 and 16 N or above 20 N while two were less stiff below 12 N.
3.2. Comparisons of sides The graphs in Fig. 3aec compare characteristics of FD curves on the left and SF curves on the right. In Fig. 3a and b the SCBs of the FD and SF curves for the tender and control sides overlap throughout the
4. Discussion The current study set out to determine patterns of movement or stiffness associated with local tenderness
Fig. 2. Representative forceedisplacement (FD) and stiffnesseforce (SF) data from two subjects. Grey dashed lines represent tender sides; black solid lines represent less tender sides.
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Fig. 3. Simultaneous confidence and prediction bands comparing tender and less sides. Grey lines represent painful sides and black lines represent less tender sides. For solid lines, thick lines indicate means and thin lines indicate simultaneous prediction bands (SPBs). For dashed lines, thick lines indicate simultaneous confidence bands (SCBs) and thin lines indicate curves from individual locations.
during unilateral PAs of the cervical spine. We found several differences in the pattern of the tender sides compared to the less tender control sides. Specifically, the tender side demonstrated greater variation of both displacement and stiffness; the tender sides demonstrated greater within-subject stiffness for all force levels above 12 N; and all individual SF curves of the tender sides were significantly different from the control side. The expected differences between sides in single measures of either displacement or stiffness however were not detected.
The pattern of differences is illustrated by comparisons of the SF curves of the tender and control sides of the representative curves shown in Fig. 2b. The middle and latter thirds the curves from the tender side diverge from the corresponding control curve, reach a peak of maximum difference and then re-approach the control curve. The effects of a similar pattern can be seen in the shape of the mean SF curves in Fig. 3b, the differences between tender and control sides in Fig. 3d and the areas where the individual tender SF curves are above the SPBs in Fig. 3f. Variations in the pattern (particularly
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variations in the force at which the stiffness of the painful side rises away from the control side) are likely to be responsible for single measures of displacement or stiffness as used in previous studies being unable to detect differences between sides in the current study. Displacement has been used to assess PA mobility in previous studies but no differences in displacement were detected in the current study. The differences in displacement may have been too small to be detected by the methods used in the current study or unilateral PAs on the cervical spine may exhibit different behaviour than PAs applied to the midline of the lumbar or thoracic spines investigated in previous studies. Stiffness of spinal PAs (slope of the latter portion of the FD curve) expressed as a constant is another parameter that has been used to characterize spinal PA stiffness. Although visual inspection of the FD curves from the current study may have suggested the stiffness approached a constant, the SF curves clearly indicated stiffness continued to change throughout the movement. The lack of constant stiffness in any region of the SF curves agreed with Nicholson et al. (2001) who found that a linear approximation of stiffness did not provide the best fit to FD curves from PAs to the lumbar spine. Variations in the force at which the stiffness of the tender side diverges from the control side may explain why single measures of displacement or stiffness were unable to detect differences between sides in the current study. 4.1. Clinical implications The findings in the current study of significant differences in stiffness at forces starting at 12 N supports the assertion by experienced clinicians of being able to detect altered PA mobility well before the end of the PA movement. The method used in this study may have in fact overestimated the minimum force necessary to manually detect differences. Clinicians will often displace overlying soft tissue to gain closer contact between their thumbs and the vertebrae being palpated. The indentor in the current study was applied in a predetermined linear direction without prior displacement of soft tissue which may have resulted in a thicker layer of soft tissue being compressed than occurs with manual palpation. A small amount of force being necessary to detect differences was also demonstrated by Marcotte et al. (2005) who found that the force used by clinicians varied from 1 to 8 N, but the level of force did not affect the accuracy of detecting the location of a known intervertebral fusion. In light of differences being detectable at such low levels of force, it is interesting to note that many of the previous studies assessing central PA stiffness in the lumbar spine considered stiffness occurring only in the latter portion of the movement at forces above 30 N (Lee and Liversidge, 1994; Latimer et al., 1996a, b; Edmondston et al., 1998; Shirley et al., 2003).
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Clinicians interpreting manual spinal PAs appear to consider aspects of the PA movements other than or in addition to the single values of displacement or stiffness previously used to describe instrumented assessments (Maher and Adams, 1995a, b). The findings of differences in patterns of stiffness throughout the PA movement may suggest some of the parameters that clinicians consider in their assessments of PA stiffness but the inferences that can be drawn from these findings are limited in several ways. Firstly, it is not known if the patterns of stiffness found in the current study could be differentiated from altered stiffness resulting from extraneous factors not addressed in this study but known to influence PA stiffness (e.g. position, respiration or regional muscle contraction). Secondly, despite the subjects being defined as asymptomatic, the control side could not be considered ‘normal’ but only less tender than the tender side. Both sides used for comparisons were tender to some extent and the sides only differed in pain intensity by an average of 2.5 out of 10 on a visual analogue scale. Finally, although the analysis in the current study was more detailed than that used in previous studies, it may not have been sufficient to determine the essential characteristics of differences in spinal PAs related to altered segmental mobility. It may be worth suggesting how clinicians’ perceptions might relate to the patterns of stiffness described in the current study. Two common terms used to describe PA movements are R1 (the point thought to correspond with the first onset of resistance) and endfeel. Petty et al. (2002) pointed out that there was resistance throughout the PA movement and suggested that R1 did not correspond with a measurable point in PA movements. The point described as R1 may, however correspond with the point where the rate of increase in stiffness changes rather than the point of first perceptible resistance. In the current study R1 may therefore correspond with the point on the stiffness graphs where the tender side diverges from the control side. Likewise defining the physical equivalent of endfeel is problematic. There is no clear end of range of PA movements as displacement continues to increase with increasing force. The location, height and shape of portions of the SF curves diverging from the control sides may therefore be parameters of interest in assessing spinal PA stiffness. Additional research is necessary using symptomatic subjects to clarify the relationship between patterns of PA stiffness and symptom production. In addition, further studies relating clinician’s perceptions with physical measurements may bring a greater objectivity to manual assessment of passive movements. 4.2. Conclusions To our knowledge, this is the first study to investigate differences in patterns of stiffness throughout PA
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movements to the cervical spine. The pattern of stiffness particularly from 12 to 16 N and 20 to 25 N is a more effective method of characterizing altered PA mobility in the cervical spine related to intervertebral dysfunction than the single measures of displacement or stiffness used in previous studies. There was a small sample size in this study so the results can only be considered as preliminary but if confirmed, these findings will assist in determining more objective criteria for characterization of spinal PA mobility for research, teaching and clinical practice. Future studies investigating assessment and interpretation of spinal PAs may need to consider parameters other than the single values of displacement or stiffness used in previous studies.
Competing interests The authors declare that they have no competing interests.
Acknowledgements NT is supported by an Australian Postgraduate Award. We would like to thank Kerrie Evans for assistance in data collection and the subjects for their participation.
Appendix. Calculation of simultaneous confidence and simultaneous prediction bands Resampling methods such as bootstrapping overcome many of the difficulties resulting from small sample sizes. For this study, 1000 simultaneous bootstrap resamples (resampling entire curves) with replication were used for all analyses. SCBs enable the comparison of mean values by enclosing the area around the sample mean curve where, for a given probability, the entire length of the true mean curve can be expected to lie. To determine the SCBs, the sample mean curves from each of the bootstrap resamples for the tender side, the less tender side and pointwise difference between the two sides were calculated. The largest pointwise standardized deviation from the grand mean that occurred on each resample mean curve (S.D.maxresample) indicated the maximum distance (in standard deviations) from any point on that resample mean curve to the grand mean curve. The 95th percentile (50th largest) S.D.maxresample (S.D.95%resample) was therefore greater than the maximum distance (in standard deviations) between any point on the remaining 95% of the sample means and the grand mean. The width of the 95% SCB around the grand mean at each point was therefore
S.D.95%resample multiplied by the pointwise standard deviation at that point. The difference between SCBs and pointwise confidence intervals could be illustrated by probabilities related to the mean curve of any future resample of the original dataset. There would be only a 5% chance that any part of the curve would lay outside of an SCB, but as each curve would contain 100 data points one would expect an average of five data points to lie outside of a pointwise series of confidence intervals. Plots of the SCBs of the tender and control sides were then overlaid and any areas where the SCBs did not overlap represented areas of the curves with significantly different means. The mean and confidence intervals of the pointwise widths of the SCBs were calculated for the tender and control group as an indicator of the variance of the curves. The SCBs of the differences between the tender and control sides were graphed and if zero was not contained within the SCBs the difference was considered to be significantly different from zero. SPBs differ from SCBs in that, for a given probability, SCBs are expected to fully enclose the true mean curve of the population while SPBs are expected to enclose individual curves from the population. The usefulness of SPBs is that when future individual curves are co-plotted with the SPBs, if any part of the new curve is outside of the SPBs, then the individual curve can be considered to be significantly different from the population used to determine the prediction band. SPBs were also calculated using bootstrap resamples each containing 10 curves. The maximum pointwise standardized deviation was calculated for each curve (S.D.maxcurve). The average of the 95th percentiles of from the bootstrap resamples S.D.maxcurve (SD95%curve) is therefore greater than the maximum distance (in standard deviations) between any point on 95% of the individual curves and the mean curve. The width of the 95% SPB of the control group around the grand mean at each point is therefore S.D.95%curve times the pointwise standard deviation at that point. Plots of individual curves of tender locations were overlaid on the SPBs of the control group. If any part of an individual curve from the tender side lies outside of the SPB of the control group, that curve can be considered to be significantly different from the control group.
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Lee R, Evans J. An in vivo study of the intervertebral movements produced by posteroanterior mobilization. Clinical Biomechanics 1997;12(6):400e8. Lee M, Liversidge K. Posteroanterior stiffness at three locations in the lumbar spine. Journal of Manipulative and Physiological Therapeutics 1994;17(8):511e6. Lee H, Nicholson LL, Adams RD. Cervical range of motion associations with subclinical neck pain. Spine 2004;29(1):33e40. Lee RY, McGregor AH, Bull AM, Wragg P. Dynamic response of the cervical spine to posteroanterior mobilisation. Clinical Biomechanics 2005;20(2):228e31. Lenhoff MW, Santner TJ, Otis JC, Peterson MG, Williams BJ, Backus SI. Bootstrap prediction and confidence bands: a superior statistical method for analysis of gait data. Gait & Posture 1999;9(1):10e7. Maher C, Adams R. Is the clinical concept of spinal stiffness multidimensional? Physical Therapy 1995;75(10):854e60. Maher C, Adams R. A psychophysical evaluation of manual stiffness Physiotherapy Australian Journal of discrimination. 1995;41:161e7. Maitland G, Hengeveld E, Banks K, English K. Maitland’s vertebral manipulation. 7th ed. Edinburgh: Elsevier/Butterworth Heinemann; 2005. Marcotte J, Normand MC, Black P. Measurement of the pressure applied during motion palpation and reliability for cervical spine rotation. Journal of Manipulative and Physiological Therapeutics 2005;28(8):591e6. Nicholson L, Maher C, Adams R, Phan-Thien N. Stiffness properties of the human lumbar spine: a lumped parameter model. Clinical Biomechanics 2001;16(4):285e92. Petty NJ, Maher C, Latimer J, Lee M. Manual examination of accessory movements-seeking R1. Manual Therapy 2002;7(1):39e43. Pool JJ, Hoving JL, de Vet HC, van Mameren H, Bouter LM. The interexaminer reproducibility of physical examination of the cervical spine. Journal of Manipulative and Physiological Therapeutics 2004;27(2):84e90. Shirley D. Manual therapy and tissue stiffness. In: Boyling JD, Jull G, editors. Grieve’s modern manual therapy. Sydney: Churchill Livingstone; 2004. p. 381e91. Shirley D, Hodges PW, Eriksson AE, Gandevia SC. Spinal stiffness changes throughout the respiratory cycle. Journal of Applied Physiology 2003;95(4):1467e75. Smedmark V, Wallin M, Arvidsson I. Inter-examiner reliability in assessing passive intervertebral motion of the cervical spine. Manual Therapy 2000;5(2):97e101. Snodgrass SJ, Rivett DA, Robertson VJ. Manual forces applied during posterior-to-anterior spinal mobilization: a review of the evidence. Journal of Manipulative and Physiological Therapeutics 2006;29(4):316e29. Squires MC, Latimer J, Adams RD, Maher CG. Indenter head area and testing frequency effects on posteroanterior lumbar stiffness and subjects’ rated comfort. Manual Therapy 2001;6(1):40e7. Sran MM, Khan KM, Zhu Q, Oxland TR. Posteroanterior stiffness predicts sagittal plane midthoracic range of motion and threedimensional flexibility in cadaveric spine segments. Clinical Biomechanics 2005;20(8):806e12. Tuttle N, Barrett R, Laakso L. Postero-anterior movements of the cervical spine: repeatability of forceedisplacement curves. Manual Therapy 2007;13(4):341e8.
Available online at www.sciencedirect.com
Manual Therapy 14 (2009) 36e44 www.elsevier.com/math
Original article
Manual physical assessment of spinal segmental motion: Intent and validity J. Haxby Abbott a,*, Timothy W. Flynn b, Julie M. Fritz c, Wayne A. Hing d, Duncan Reid e, Julie M. Whitman b a
Centre for Physiotherapy Research, School of Physiotherapy, University of Otago, PO Box 56, Dunedin, New Zealand b Department of Physical Therapy, Regis University, Denver, CO, USA c Division of Physical Therapy, University of Utah, Salt Lake City, UT, USA d School of Physiotherapy, Auckland University of Technology, Auckland, New Zealand e Division of Rehabilitation and Occupation Studies, Auckland University of Technology, Auckland, New Zealand Received 19 March 2007; received in revised form 10 August 2007; accepted 13 September 2007
Abstract Validity of a clinical test can be defined as the extent to which the test actually assesses what it is intended to assess. In order to investigate the validity of manual physical assessment of the spine, it is therefore essential to establish what physical therapists intend to assess when they are applying these tests. The aims of this study were to (1) establish what manual physical therapists are intending to assess while applying passive intervertebral motion tests; and (2) examine the face validity and content validity for manual physical assessment of the spine. We surveyed 1502 members of the national manual physical therapist organisations of New Zealand and the United States of America using a web-based survey instrument. Sixty-six percent of 466 respondents believed passive accessory intervertebral motion (PAIVM) tests were valid for assessing quantity of segmental motion, and 76% believed passive physiologic intervertebral motion (PPIVM) tests were valid for assessing quantity of segmental motion. Ninety-eight percent of manual physical therapists base treatment decisions at least in part on the results of segmental motion tests. Quality of resistance to passive segmental motion was considered of greater importance than quantity of kinematic motion during PAIVM tests, while the quality of complex kinematic motion was considered of greater importance than quantity of displacement kinematics during PPIVM tests. Manual physical therapists accept the face validity of manual physical assessment of spinal segmental motion to a great extent, however a minority voice scepticism. Content validity is dominated by concepts of segmental kinematics and the forceedisplacement relationship. Intent of assessment does, however, vary widely between therapists. These data will inform the design of concurrent validity studies. Further work is recommended to increase consistency of intent, methodology and terminology in manual physical assessment of the spine. Ó 2007 Elsevier Ltd. All rights reserved. Keywords: Physical therapy techniques; Manual therapies
1. Introduction Expert clinicians believe that lumbar spinal segmental (intervertebral) motion is an important factor in low * Corresponding author. Tel.: þ64 3 479 5133; fax: þ64 3 479 8414. E-mail address:
[email protected] (J.H. Abbott). 1356-689X/$ - see front matter Ó 2007 Elsevier Ltd. All rights reserved. doi:10.1016/j.math.2007.09.011
back pain (LBP) and that it can be assessed using physical examination procedures (Binkley et al., 1993). Some form of physical assessment of spinal motion is integral to almost all classification systems used by expert musculoskeletal physical therapists (PTs) to diagnose subgroups within non-specific spinal disorders (Paris, 1985; Nyberg, 1993; Delitto et al., 1995; Riddle, 1998;
J.H. Abbott et al. / Manual Therapy 14 (2009) 36e44
Van Dillen et al., 1998; Laslett and van Wijmen, 1999; Petersen et al., 1999; Flynn et al., 2002; Cook et al., 2006). Two common manual physical examination procedures used by PTs to detect spinal segmental mobility are passive accessory intervertebral motion tests (PAIVMs) and passive physiological intervertebral motion tests (PPIVMs) (Abbott et al., 2005). The face validity of these manual physical examination tests for detecting spinal segmental mobility is not universally accepted. The ‘content universe’ of properties of motion the assessor is expected to assess [i.e. all of what is entailed in the entity the test is intended to measure, and the relative importance of each component of that entity (Portney and Watkins, 1993)] is not known. The literature contains a very wide range of descriptors of what may be felt with manual segmental mobility assessment (Maher et al., 1998; Cook et al., 2006), although two studies suggest that the key concepts are quantity of motion and the forceedisplacement relationship (Binkley et al., 1993; Maher et al., 1998). Beyond this, little is known about the relative importance placed on the quantities of motion that may be assessed, or the various characteristics that may be perceived. The aim of this study was to investigate the face validity and content validity of manual assessment of spinal segmental motion. We aimed to examine: (1) the extent to which manual PTs accept the face validity of two common manual physical assessment procedures, PAIVMs and PPIVMs, for detecting spinal segmental motion; and (2) the relative importance of each component of the core ‘content universe’ for these tests.
2. Methods The target population for this study was members of the New Zealand Manipulative Physiotherapists Association (NZMPA) and the American Academy of Orthopaedic Manual Physical Therapists (AAOMPT). We included all PTs who: (a) were financial members of
37
these organisations in December 2005; and (b) had an active email address on file with the organisation. This protocol was reviewed by the Institutional Review Board of Regis University, and was designated IRB Exempt. Development of the survey instrument was approached in three phases. The principal investigator (JHA) developed version 1 as part of earlier research (Abbott, 2005). Pilot data from that research informed version 2, which was further developed through consultation with the co-investigators and colleagues. We then designed version 3 using WebSurveyorÒ (www.websurveyor.com), and pilot-tested the survey instrument on a small sample of manual PTs (n¼15). Based on feedback from the pilot test, we reworded questions and responses where necessary for the final version. We populated the WebSurveyor database with the list of email addresses provided by NZMPA and AAOMPT. The WebSurveyorÒ program sent an email invitation to eligible PTs. Respondents submitted completed surveys via WebSurveyorÒ, which logged the submission, added the responses to the results database, and withheld further reminder notices to the email address of the respondent. Non-respondents were emailed three reminder notices at 1-week intervals. Our examination of the extent of face validity was based on three questions. In the first question, participants were asked to choose (on a Likert scale) how accurate they believe each of the physical assessment procedures (PAIVMs and PPIVMs) are for estimating the quantity of movement present at a lumbar segment. In the second question, participants were asked if they believe that it is possible, from the clinical examination, to recognise restricted or excessive lumbar segmental motion. The third question relied on the assumption that participants demonstrated acceptance of face validity if they reported that, in clinical practice, they select different treatment options for patients with LBP on the basis of lumbar segmental motion findings.
Table 1 Responses available to respondents for survey questions on intent of manual physical assessment and basis for comparative decisions Responses available for ranking: intent of manual physical assessment
Responses available for ranking: basis for comparative decisions
Position of the vertebrae, or normality of the position of vertebrae during motion Quantity of angle of spinal bending Quantity of translation of the vertebrae Quality of resistance (e.g. greater or lesser stiffness, forcedisplacement relationship) Quality of end-feel or tissue-feel (e.g. capsule, disc, muscle, ligament, bony, cartilage) Quality of the motion during the movement, or normality of the path of vertebral motion The patient’s pain response (verbal or observed) Other
The mobility you expect for that segmental level, taking into account the patient’s age and/or body type The mobility you expect for that segmental level, compared to your experience of assessing the same segmental level in other patients and normal individuals The mobility you expect for that segmental level, compared to other segments above and below The patient’s pain response (verbal or observed) to the procedure Other
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J.H. Abbott et al. / Manual Therapy 14 (2009) 36e44
We then examined the two principal aspects of content validity: the ‘content universe’ and the relative order of importance of each component of that content universe (Portney and Watkins, 1993). We identified, from the manual PT literature, key properties of motion within the content universe related to intent of manual segmental motion assessment and incorporated these as available responses to survey questions (Table 1). To establish the basis on which PTs make comparative decisions regarding these motion properties, we asked participants to rank the choices available from most important to least important. Respondents could leave blank any choice that did not represent their modus operandi. We captured other components of the content universe, and other bases for decision-making, by including an ‘‘other’’ response. Respondents choosing ‘‘other’’ were invited to submit a free-text response. We also included a request for further comments at the end of the survey instrument. These were analysed qualitatively by two investigators (WH, DR), and independently by another investigator (JHA) using Editing Analysis Style principles (Crabtree and Miller, 1992), until all major themes were identified. The minimum number of like responses necessary to constitute a theme was set at 5%. A hierarchy of themes was derived from the data: meta-themes, themes, and (where necessary) subthemes. The final themes were subsequently agreed by consensus between the three investigators. Descriptive statistics (number, percent) were used to summarise the data. For ranked responses, we counted the frequency each response was ranked at each ranking level, and present only the frequency they were ranked by respondents as most important (#1) and second most important (#2). We calculated the frequency and proportion of free-text responses in each theme which arose in the qualitative analysis.
3. Results Four hundred sixty-six (31%) of 1502 eligible PTs responded. Characteristics of the participants are described in Table 2. The majority of respondents (65.9%; 95% confidence interval 61.5%, 70.0%) believed that central postero-anterior PAIVMs are ‘somewhat accurate’ or ‘very accurate’ for estimating the quantity of movement present at a lumbar segment (for example identifying restricted, normal, excessive movement) (Table 3). A still higher proportion (76.2%; 72.1%, 79.8%) believe that PPIVMs are ‘somewhat accurate’ or ‘very accurate’ for estimating the quantity of movement present at a lumbar segment (Table 3). Most respondents (97.6%; 95.8%, 98.6%) report that they select different treatment options for patients with LBP at least partly on the basis of lumbar segmental motion findings.
Table 2 Characteristics of respondents Respondents Total
466/1502
(31%)
Country of PT practice USA NZ Other
395 64 2
(86%) (14%) (0.2%)
Direct patient care >30 h/week 21e30 h/week 20 or less hours/week
280 65 115
(61%) (14%) (25%)
Low back pain patients >30% of caseload 10e30% of caseload <10% of caseload
280 154 25
(61%) (34%) (5%)
Entry level PT degree Certificate/diploma/other Bachelors Masters Clinical doctorate (DPT)
66 212 156 27
(14%) (46%) (34%) (6%)
Highest earned degree Certificate/diploma/other Bachelors Masters Clinical doctorate Research doctorate
71 100 170 81 38
(17%) (22%) (37%) (18%) (8%)
Professional designationsa ABPTS certified (e.g. OCS) MNZMPA or FAAOMPT Neither
188 165 152
(48%) (41%) (38%)
PT, physical therapy or physiotherapy; USA, United States of America; NZ, New Zealand; DPT, Doctor of Physical Therapy degree; ABPTS, American Board of Physical Therapy Specialties; OCS, Orthopaedic Certified Specialist; NZMPA, fully qualified Member of the New Zealand Manipulative Physiotherapists Association; FAAOMPT, Fellow of the American Academy of Orthopaedic Manual Physical Therapists. a Percentages exceed 100% because respondents may be in more than one category.
When asked to consider what they are intending to assess when performing central postero-anterior PAIVMs, the greatest proportion of respondents ranked the patient’s pain response (verbal or observed) as most Table 3 Responses to the questions ‘‘Indicate how accurate you believe [central P-A PAIVMs/PPIVMs] are for estimating the quantity of movement present at a lumbar segment (for example identifying restricted, normal, excessive movement)’’
Not at all accurate Somewhat inaccurate Somewhat accurate Very accurate
PAIVMs: number (%)a
PPIVMs: number (%)b
42 114 250 51
20 89 279 70
(9.2%) (24.9%) (54.7%) (11.2%)
(4.4%) (19.4%) (60.9%) (15.3%)
PAIVMs, passive accessory intervertebral motion tests; PPIVMs, passive physiological intervertebral. a Percent of valid data, 9 (1.9%) missing. b Percent of valid data, 8 (1.7%) missing.
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J.H. Abbott et al. / Manual Therapy 14 (2009) 36e44
important (31.8% ranked this response #1; 18.8% ranked it #2). Quality of resistance (e.g. greater or lesser stiffness, forceedisplacement relationship) was the next most highly ranked (28.8 #1; 28.8 #2), followed by quantity of translation of the vertebrae (11.5; 13.7). Further results are presented in Fig. 1. When asked to consider what they intend to assess when they perform PPIVMs, quality of the motion during the movement (or normality of the path of vertebral motion) was ranked most important by respondents (29.7% ranked this response #1; 24.8% ranked it #2). Quantity of angle of spinal bending (e.g. flexion, extension, or sidebending) was the next most highly ranked (19.5 #1; 16.6 #2), followed by position of the vertebrae during motion (13.7; 9.8). Further results are presented in Fig. 2. How respondents judge spinal mobility during passive intervertebral motion assessment procedures, is presented in Fig. 3. The free-text responses offered by participants fell into two meta-themes: justification and clarification. The themes revealed for PAIVMs and PPIVMs were not dissimilar, so were collapsed into common themes. Results from the 73 free-text responses offered are listed in Table 4. Regarding what manual PTs intend to assess using manual tests of segmental motion, comments suggested that interaction between properties (or domains) are assessed by some respondents: ‘‘A general sense of movement quality related to quality determinants such as palpable resistance, muscle spasm, and related to other patient psycho-physiological responses.’’
Property Position of vertebra
Property Position of vertebra
Ranked #1, #2
Quantity of angle Quantity of translation
19. 5 11. 1
Quality of resistance
6.7
Quality of end-feel
5.3
16.6 10.7
17.3 13. 2
Quality of motion path Pain response
9.8
13. 7
29. 7 12.0
24. 8
7.3
Other
Fig. 2. Responses to the question ‘‘Consider what you are intending to assess when you perform central PPIVMs. Using the drop-down boxes, please rate the following choices in rank order, from most important to least important.’’ Data represent the proportion (in percent) of manual physical therapists who ranked each response as of the greatest importance (dark red bar) and second greatest importance (light blue bar) during assessment of spinal segmental motion. Four hundred and fifty-one (96.8% of) respondents gave at least 1 ranked response, 440 (94.4% of) respondents gave 2 or more ranked responses. Data were missing for 15 (3.2%) participants.
‘‘The pain-range behavior which I’ll define as the where in range is the pt’s concordant sign reproduced and with how much force.’’ Several respondents were sceptical about the validity of manual physical assessment of spinal segmental motion: ‘‘I do not use this technique in general. There is very weak EBP.’’ ‘‘Very rarely use them. The literature indicates they are of little value with poor reliability to determine a level let alone anything else of use.’’
Ranked #1 , #2 4.6
Quantity of angle Quantity of translation
11. 5
Quality of resistance
28. 8
Quality of end-feel
9.4
Quality of motion path
11. 5
Pain response
13. 7 28. 8 24. 1 9.7 31. 8
18. 8
Other
Judgement made by mobility expected compared to:
Ranked #1 , #2
That segmental level considering age & body type
14.4
That segment allevel cf. other patients & normals
13.7
Segments above & below within the same patient Pain response Other
Fig. 1. Responses to the question ‘‘Consider what you are intending to assess when you perform central P-A PAIVMs. Using the drop-down boxes, please rate the following choices in rank order, from most important to least important.’’ Data represent the proportion (in percent) of manual physical therapists who ranked each response as of the greatest importance (dark red bar) and second greatest importance (light blue bar) during assessment of spinal segmental motion. Four hundred and fifty-nine (98.5% of) respondents gave at least 1 ranked response, 452 (97% of) respondents gave 2 or more ranked responses. Data were missing for 7 (1.5%) participants.
35.1 29.7 60.6
21.4
8.9 12.8 2.4
Fig. 3. Responses to the question ‘‘Consider how you judge spinal mobility. Do you base your judgments on any of the following? Using the drop-down boxes, please rate the following choices in rank order, from most important to least important.’’ Data represent the proportion (in percent) of manual physical therapists who ranked each response as of the greatest importance (dark red bar) and second greatest importance (light blue bar) during assessment of spinal segmental motion. Four hundred and fifty-nine (98.5% of) respondents gave at least 2 ranked responses. Data were missing for seven (1.5%) participants.
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J.H. Abbott et al. / Manual Therapy 14 (2009) 36e44
Table 4 Themes identified from ‘other’ responses to the questions ‘‘Consider what you are intending to assess when you preform.’’ PAIVMs and PPIVMs Themea
Number (%)b
Examples from the data
Interaction of domains
12 (16%)
‘‘Pain response combined with quantity of motion’’ ‘‘Relationship of pain and resistance’’ ‘‘Here I am looking for different things if the patient’s condition is acute or more chronic’’ ‘‘Influence of muscle length on vertebral movement’’ ‘‘Paraspinal muscle reactivity or reaction’’ ‘‘Ability to reproduce patient’s symptoms’’ ‘‘I don’t use this technique in general. There is very weak EBP’’ ‘‘The literature indicates they are of little value with poor reliability.’’
Muscle-related
7 (10%)
Symptom-related Scepticism
5 (7%) 4 (5%)
PAIVMs, passive accessory intervertebral motion tests; PPIVMs, passive physiological intervertebral motion tests. a Two other common themes (movement-related and position by palpation) are not listed as they replicate responses available in the survey instrument. b Number (%) of 73 comments represented by theme. Percentages do not sum to 100, because some comments either could not be classified by theme, or represented responses available in the survey questions (Table 1).
Regarding how manual PTs make comparative judgments about the motion of a spinal segment, one main theme was identified from the 37 free-text responses offered by respondents (Table 5). Respondents emphasised the importance of the patient’s history and other clinical findings, indicating that the influence of pretest probability is taken into account: ‘‘Expected mobility for that segment based on the patient’s history of injury and course of symptom progression/regression.’’ ‘‘Patients response to active movement, observation skills patterns of movement and postural influences, i.e. descrepencies [sic] in anatomy, weak muscles etc.’’ Comments offered in the final free-text question revealed three main themes (Table 6). Among the 144 free-text responses, many respondents commented that manual tests of segmental motion are but a part of a more comprehensive set of data collected to inform clinical decision-making: ‘‘PPIVM and PAIVM must be used along with other tests to rule in or out diagnostic hypotheses that were formed from the history and subjective report. One test does not stand alone.’’ The theme of scepticism regarding the reliability and validity of manual tests of segmental motion continued: ‘‘.I believe the literature to date does not support this approach.’’ although some acknowledged evidence supporting their valid use: ‘‘I rarely use PPIVMs now. Unreliable and invalid. I use them only to identify the anatomical [sic] segment once I have chosen to perform a manipulative procedure. I use PAIVMs primarily for pain response (provocation or abolition). I now consider (on the basis of current evidence) that PAIVMs may have value in a composite of
clinical findings for identifying patients most likely to respond to manipulation (Flynn, Childs, Fritz papers).’’ ‘‘As noted in the lit [literature] the reliability of PPIVM’s and PAIVM’s is poor however combined with other subjective and objective data we can subgroup LBP patients and apply CPR’s [clinical prediction rules].’’
4. Discussion Our data indicate that most (66e76%) manual PT respondents have faith in the accuracy of manual segmental mobility assessment procedures for detecting quantity of spinal segmental motion. Few (5e9%) expressed scepticism, or rated the procedures as ‘‘not at all accurate’’. The overwhelming majority (98%) base patient treatment choices at least partly on the basis of lumbar segmental motion assessment findings. These
Table 5 Themes identified from ‘other’ responses to the question ‘‘Consider how you judge spinal mobility. Do you base your judgments on.’’ Theme
Number (%)a Examples from the data
22 (59%) Taking other history and physical findings into account (sum of subthemes)b
‘‘Based on medical/surgical history and what patient presents in his subjective history/complaints’’ ‘‘Patient history/description of activities/positions that produce the pain/catching; irritability of presentation’’ ‘‘Range of motion testing; observing quality and quantity of motion’’
a Number (%) of 37 comments represented by theme. Percentages do not sum to 100, because some comments could not be classified by theme, or represented responses available in the survey questions (Table 1). b Subthemes identified were: History examination; Symptoms (including reproduction of); Other physical examination items.
J.H. Abbott et al. / Manual Therapy 14 (2009) 36e44
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Table 6 Themes identified from responses to the question ‘‘Would you like to comment on any aspect of the use of PAIVM or PPIVM assessments for the examination of the spine?’’ Theme
Number (%)a
Examples from the data
Part of a multi-factorial process
49 (34%)
I do it differently
14 (10%)
Scepticism
13 (9%)
Experience is necessary to use these tests
10 (7%)
‘‘I view PPIVM and PAIVM as part of a comprehensive examination process in orthopedic [sic] physical therapy. Findings are taken within the context of all physical examination findings, as well as the subjective portion of the patient examination’’ ‘‘I perform PAIVMs superior and inferior directions to access facet restrictions, not in a PeA direction’’ ‘‘Generally don’t use them due to McKenzie training’’ ‘‘Questionable interrater reliability’’ ‘‘I rarely use PPIVMs now. Unreliable and invalid’’ ‘‘I also think that the ability of a therapist to consistently use these tools increases there [sic] reliability and validity’’ ‘‘A spinal evaluation is not complete unless PPIVM and/or PAIVM are performed!’’
Essential to the clinical examination
7 (5%)
PAIVM, passive accessory intervertebral motion; PPIVM, passive physiological intervertebral motion. a Number (%) of 144 comments represented by theme. Percentages do not sum to 100, because some comments could not be classified by theme, or represented responses available in the survey questions (Table 1).
findings are consistent with previous research indicating that segmental motion is an important clinical finding in the examination and diagnosis of patients with spinal pain (Binkley et al., 1993; Cook et al., 2005a, 2006), and PTs are confident in diagnosing segmental motion disorders (Cook et al., 2005b). Our data concur with Cook and colleagues (2005b), who found that over 70% of manual PTs in their Dephi study ‘often’ or ‘very often’ use palpable segmental mobility abnormalities in the diagnosis of spinal instability (Cook et al., 2005b). We therefore conclude that acceptance of the face validity of manual segmental mobility assessment procedures is strong among manual PTs. Our data indicate that, overall, quantity of motion and quality of the forceedisplacement relationship were the dominant concepts within the content universe of spinal segmental motion, concurring with earlier research (Binkley et al., 1993; Maher et al., 1998; Cook et al., 2006). Few respondents ranked ‘other’ properties of segmental motion as highly important, for either PAIVM or PPIVM testing, which supports the view that the content universe of what is intended to be assessed during these manual tests was adequately represented by the responses available (see Table 1). Within these responses, however, considerable variability was seen in the data. Patients’ pain response to PAIVM testing was rated of highest importance by more respondents (32%) than rated any of the motion properties highest, which is consistent with research indicating that these assessment procedures are accurate for the detection of a painful segment (Phillips and Twomey, 1996). A large proportion of respondents (58%: equally split between #1 and #2 rankings) intend to assess the quality of resistance to movement (i.e. greater or lesser stiffness; the force-displacement relationship) during PAIVM testing, as found by (Maher et al., 1998), and supported by
experimental research using a proxy criterion standard for stiffness (Chiradejnant et al., 2003a). A wide variety of other motion properties were ranked highly by respondents. Manual PTs also commonly use PAIVM tests to assess quantity of translation and the quality of the ‘end-feel’ of segmental motion. Few studies have measured sagittal translation motion, however, those that have report that the magnitude of motion is small (Lee and Evans, 2000), may not be manually perceptible (Lee and Evans, 1997), and may be in the opposite direction to that which some manual PT theories might predict. Posterior translation seems to occur because of the spine behaving like a flexible beam undergoing three-point bending, rather than anterior translation of one vertebra on the neighbouring vertebra below (Lee and Evans, 1997). Although these in vitro and in vivo laboratory studies findings dispute the face validity of manual segmental mobility assessment, two recent criterion-related validity studies independently concluded that PAIVMs may possess concurrent validity for detecting excessive sagittal translation (Abbott et al., 2005; Fritz et al., 2005a). Despite differing methodology and populations, their results were highly consistent, which provides rigorous independent validation (Abbott, 2007). Although in one of the studies (Fritz et al., 2005a) the likelihood ratio for a positive test (LRþ) was not statistically significant, it appears likely that this may be due to type 2 error as the other study (Abbott et al., 2005) with a larger sample size found almost exactly the same LRþ estimate, and was statistically significant. Similarly, in one of the studies (Abbott et al., 2005) the likelihood ratio for a negative test (LR-) was not statistically significant, however, again this is likely to be type 2 error, as the study with the higher prevalence of excessive sagittal translation (Fritz et al., 2005a) found a highly comparable LRestimate and was statistically significant. The magnitude
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of these associations is, however, small, indicating that: (a) a single clinical examination procedure in isolation has only weak diagnostic value; and possibly also that: (b) the kinematic properties measured as a criterion in these studies may not adequately represent the content universe of what manual PTs are assessing while performing these examination procedures. Research indicates that sagittal rotation occurs during PAIVM testing (Powers et al., 2003; Kulig et al., 2004, 2007; Beneck et al., 2005; Lee et al., 2005), although they are noted to be small, leading some authors to speculate that accurate detection by manual means would unlikely (Lee and Evans, 1997). Lee and Evans (1997) also note that the vertebrae rotate and translate simultaneously, and suggest it unlikely the assessing therapist would be able to discriminate the component movement properties. Limited motion will certainly be of a small magnitude, and it is unclear whether excessive sagittal rotation is an important factor associated with LBP (Abbott et al., 2005, 2006). Our data, however, suggest that very few manual PTs intend to assess sagittal rotation during PAIVM testing, which diminishes the external validity of such speculation. There have been few technical studies of PPIVMs, however, excessive sagittal translation motion has been shown to be more readily detected by flexione extension in the side-lying position than by standing flexioneextension (Wood et al., 1994), and there is preliminary evidence that PPIVMs performed in side-lying may have moderate validity for detecting excessive sagittal translation, however, further research must be done to confirm these findings (Abbott and Mercer, 2003; Abbott et al., 2006). No studies have yet examined complex kinematics during spinal segmental mobility testing. The quality of the path of motion perceived by the assessor during PPIVM testing was ranked of highest importance by respondents, both in terms of #1 ratings and the aggregate of #1 and #2 ratings. This indicates that complex kinematics were considered more important than simple displacement kinematics (such as quantity of angledsecond most highly rateddand quantity of translation). This proposition will pose technical difficulties to researchers choosing a reference standard for assessing the criterion-related validity of PPIVM testing, however, emerging evidence both supports the relative importance of complex kinematics over simple displacement kinematics in patients with LBP, and offers technical solutions to measuring it (Abbott, 2005; McCane et al., 2006; Teyhen et al., 2007). The data we have provided on manual PTs intent will inform researchers in the design and interpretation of criterion-related concurrent validity studies, helping to ensure a match between intent and an appropriate reference standard. The present data indicate that manual PTs’ intent of assessment encompasses more than one
domain, therefore when interpreting the results of criterion-related concurrent validity studies readers should take this fact into account. Criterion-related validity studies may underestimate validity if they examine only one domain, such as sagittal translation, without examining other important domains, such as stiffness. Estimates of the actual validity must take into account criterion-related validity of the important biomechanical domains therapists intend to assess concurrently (such as displacement, aberrant path of motion, and stiffness) as well as predictive validity. With little evidence of the validity of manual physical assessment procedures, our data suggest that some manual PTs may have turned to research investigating their reliability as a proxy measure to support or refute face validity. We suggest that it is a poor choice of proxy for three principal reasons. Firstly, we refer the reader to (Wainner, 2003) for enlightening data and argument on why low reliability may not preclude diagnostic or prognostic utility, although it must be noted that the data Wainner presents are single estimates from different studies, indicating that further research is required to adequately support the theory he presents. Secondly, the threshold for how reliable a test must be in order to be useful depends on several factors, not least being the consequences of an erroneous result (Rothstein, 2001; Wainner, 2003). And thirdly, usefulness (i.e. validity) is a more important property of a test than reliability, but is generally more difficult to study (Rothstein, 2001). There is growing evidence that manual physical assessment procedures are useful, in that they demonstrate predictive validity both for the purpose of making treatment decisions and for outcome, particularly when combined with other factors in a multivariate decision rule (Chiradejnant et al., 2002; Flynn et al., 2002; Fritz et al., 2003, 2004, 2005b; Childs et al., 2004; Hicks et al., 2005), although not all studies support these propositions (Haas et al., 2003; Chiradejnant et al., 2003b). Our data, indicating that the majority of manual PTs believe manual physical assessment procedures are moderately (somewhat) accurate, and overwhelmingly use the results of those procedures to make treatment decisions, indicates that manual PTs practice is consistent with the available evidence on usefulness. Our data also indicate that manual PTs recognise that the validity of these tests is not strong enough to stand alone, so use them in conjunction with other observations, tests and measures. A plausible explanation for poor reliability, according to Maher et al. (1998), may be that therapists’ knowledge of what biomechanical properties they are able to assess, and what properties are important in LBP, is inadequate. Terminology is inconsistent and often jargon-filled (Maher et al., 1998). We concur with this view, and believe that this inadequate knowledge base and terminology may explain the considerable
J.H. Abbott et al. / Manual Therapy 14 (2009) 36e44
variation in the data from the respondents to this study. Consistent methodology and terminology grounded in sound biomechanical and clinical evidence may facilitate communication between teacher and student; therapist and patient; clinician and researcher; and between members of the interdisciplinary health-care team. Conclusions drawn from these results must take into account the strengths and limitations of the data. The data represent a large sample of clinically active manual physical therapists across two countries, suggesting international generalisability of the results, however, the small sample from New Zealand (due to its smaller population) does not permit subgroup comparisons. Respondent bias may have inflated our estimates of face validity, because it is likely the 31% of eligible manual PTs who responded have a greater interest in, and therefore belief in, the validity of the manual physical assessment techniques in question. As we were not able to capture a sample of non-respondents, we cannot discount the possibility that the responses of participants may differ from those of non-participating manual PTs. However, the possibility of respondent bias is mitigated by evidence of relatively high levels of scepticism regarding these assessment techniques. The use of prepared responses that respondents were asked to rank in order of importance may have led to bias, however, this is mitigated by the fact that respondents did not offer a large number of free-text responses, and very few of these were ranked highly by respondents.
5. Conclusions Manual physical therapists attribute moderate to strong face validity to manual passive assessment techniques, both for assessing spinal segmental motion and as a basis for determining what type of intervention is indicated. There remains some scepticism regarding the validity of manual passive assessment techniques, despite growing evidence of their concurrent and predictive validity. This scepticism is associated with the perception of low reliability. Our data concerning content validity indicate that manual passive assessment techniques are intended to provide the therapist with information on the location of a painful segment, the quality of the forceedisplacement relationship, the quantity of segmental motion, and to a much lesser extent the underlying patho-anatomical basis for any abnormality detected. These results will inform the design and interpretation of criterion-related validity studies. We recommend teachers and practitioners of manual physical assessment techniques adopt scientifically sound and consistent methodology and terminology in describing the intent and content of these assessment procedures.
43
Acknowledgments Thanks AAOMPT, NZMPA, in particular Ken Olsen and Vicki Reid; Dr Darren Rivett; and all the manual physical therapists who took the time to complete and submit this survey.
References Abbott JH. Accuracy in the diagnosis of lumbar segmental mobility disorders. Ph.D. Thesis, University of Otago, Dunedin, 2005. Abbott JH. Passive intervertbral motion tests for diagnosis of lumbar instability. Australian Journal of Physiotherapy 2007;53(1):66. Abbott JH, Mercer SR. Lumbar segmental hypomobility: criterionrelated validity of clinical examination items (a pilot study). New Zealand Journal of Physiotherapy 2003;31(1):3e9. Abbott JH, McCane B, Herbison P, Moginie G, Chapple C, Hogarty T. Lumbar segmental instability: a criterion-related validity study of manual therapy assessment. BMC Musculoskeletal Disorders 2005;6:56. Abbott JH, Fritz JM, McCane B, Shultz B, Herbison P, Lyons B, et al. Lumbar segmental mobility disorders: comparison of two methods of defining abnormal displacement kinematics in a cohort of patients with non-specific mechanical low back pain. BMC Musculoskeletal Disorders 2006;7:45. Beneck GJ, Kulig K, Landel RF, Powers CM. The relationship between lumbar segmental motion and pain response produced by a posterior-to-anterior force in persons with nonspecific low back pain. Journal of Orthopaedic & Sports Physical Therapy 2005;35(4):203e9. Binkley J, Finch E, Hall J, Black T, Gowland C. Diagnostic classification of patients with low back pain: report on a survey of physical therapy experts. Physical Therapy 1993;73(3):138e50. Childs JD, Fritz JM, Flynn TW, Irrgang JJ, Johnson KK, Majkowski GR, et al. A clinical prediction rule to identify patients with low back pain most likely to benefit from spinal manipulation: a validation study. Annals of Internal Medicine 2004;141(12): 920e8. Chiradejnant A, Latimer J, Maher CG, Stepkovitch N. Does the choice of spinal level treated during posteroanterior (pa) mobilisation affect treatment outcome? Physiotherapy Theory and Practice 2002;18(4):165e74. Chiradejnant A, Maher CG, Latimer J. Objective manual assessment of lumbar posteroanterior stiffness is now possible. Journal of Manipulative and Physiological Therapeutics 2003;26(1):34e9. Chiradejnant A, Maher CG, Latimer J, Stepkovitch N. Efficacy of ‘‘therapist-selected’’ versus ‘‘randomly selected’’ mobilisation techniques for the treatment of low back pain: a randomised controlled trial. Australian Journal of Physiotherapy 2003;49(4):233e41. Cook C, Brismee JM, Fleming R, Sizer Jr PS. Identifiers suggestive of clinical cervical spine instability: a delphi study of physical therapists. Physical Therapy 2005;85(9):895e906. Cook C, Brismee JM, Sizer PS. Factors associated with physiotherapists’ confidence during assessment of clinical cervical and lumbar spine instability. Physiotherapy Research International 2005;10(2): 59e71. Cook C, Brismee JM, Sizer Jr PS. Subjective and objective descriptors of clinical lumbar spine instability: a delphi study. Manual Therapy 2006;11(1):11e21. Crabtree BF, Miller WL. Doing qualitative research. Newbury Park, London: Sage; 1992. p. 18e20. Delitto A, Erhard RE, Bowling RW. A treatment-based classification approach to low back syndrome: identifying and staging patients for conservative treatment. Physical Therapy 1995;75(6):470e85.
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Flynn T, Fritz J, Whitman J, Wainner R, Magel J, Rendeiro D, et al. A clinical prediction rule for classifying patients with low back pain who demonstrate short-term improvement with spinal manipulation. Spine 2002;27(24):2835e43. Fritz JM, Whitman JM, Flynn TW, Wainner RS, Childs JD. Clinical factors related to the failure of individuals with low back pain to improve with spinal manipulation. Journal of Orthopaedic & Sports Physical Therapy 2003;33:A4e5. Fritz JM, Whitman JM, Flynn TW, Wainner RS, Childs JD. Factors related to the inability of individuals with low back pain to improve with a spinal manipulation. Physical Therapy 2004;84(2):173e90. Fritz JM, Piva SR, Childs JD. Accuracy of the clinical examination to predict radiographic instability of the lumbar spine. European Spine Journal 2005;14(8):743e50. Fritz JM, Whitman JM, Childs JD. Lumbar spine segmental mobility assessment: an examination of validity for determining intervention strategies in patients with low back pain. Archives of Physical Medicine and Rehabilitation 2005;86(9):1745e52. Haas M, Groupp E, Panzer D, Partna L, Lumsden S, Aickin M. Efficacy of cervical endplay assessment as an indicator for spinal manipulation. Spine 2003;28(11):1091e6 [discussion 6]. Hicks GE, Fritz JM, Delitto A, McGill SM. Preliminary development of a clinical prediction rule for determining which patients with low back pain will respond to a stabilization exercise program. Archives of Physical Medicine and Rehabilitation 2005;86(9):1753e62. Kulig K, Landel R, Powers CM. Assessment of lumbar spine kinematics using dynamic mri: a proposed mechanism of sagittal plane motion induced by manual posterior-to-anterior mobilization. Journal of Orthopaedic & Sports Physical Therapy 2004; 34(2):57e64. Kulig K, Powers CM, Landel RF, Chen H, Fredericson M, Guillet M, et al. Segmental lumbar mobility in individuals with low back pain: in vivo assessment during manual and self-imposed motion using dynamic mri. BMC Musculoskeletal Disorders 2007;8:8. Laslett M, van Wijmen P. Low back and referred pain: diagnosis and a new system of classification. New Zealand Journal of Physiotherapy 1999;27(2):5e14. Lee R, Evans J. An in vivo study of the intervertebral movements produced by posteroanterior mobilization. Clinical Biomechanics (Bristol, Avon) 1997;12(6):400e8. Lee RY, Evans JH. The role of spinal tissues in resisting posteroanterior forces applied to the lumbar spine. Journal of Manipulative & Physiological Therapeutics 2000;23(8):551e6.
Lee RY, McGregor AH, Bull AM, Wragg P. Dynamic response of the cervical spine to posteroanterior mobilisation. Clinical Biomechanics (Bristol, Avon) 2005;20(2):228e31. Maher CG, Simmonds M, Adams R. Therapists’ conceptualization and characterization of the clinical concept of spinal stiffness. Physical Therapy 1998;78(3):289e300. McCane B, King TI, Abbott JH. Calculating the 2d motion of lumbar vertebrae using splines. Journal of Biomechanics 2006;39:2703e8. Nyberg R. Clinical assessment of the low back: active movement and palpation testing. In: Basmajian JV, Nyberg R, editors. Rational manual therapies. Baltimore: Williams & Wilkins; 1993. p. 97e140. Paris SV. Physical signs of instability. Spine 1985;10(3):277e9. Petersen T, Thorsen H, Manniche C, Ekdahl C. Classification of nonspecific low back pain: a review of the literature on classifications systems relevant to physiotherapy. Physical Therapy Reviews 1999;4(4):265e81. Phillips DR, Twomey LT. A comparison of manual diagnosis with a diagnosis established by a uni-level lumbar spinal block procedure. Manual Therapy 1996;1(2):82e7. Portney LG, Watkins MP. Foundations of clinical research: applications to practice. East Norwark, CT: Appleton & Lange; 1993. Powers CM, Kulig K, Harrison J, Bergman G. Segmental mobility of the lumbar spine during a posterior to anterior mobilization: assessment using dynamic mri. Clinical Biomechanics 2003;18(1): 80e3. Riddle DL. Classification and low back pain: a review of the literature and critical analysis of selected systems. Physical Therapy 1998;78(7):708e37. Rothstein JM. Sick and tired of reliability? Physical Therapy 2001;81(2):774e5. Teyhen DS, Flynn TW, Childs JD, Abraham LD. Arthrokinematics in a sub-group of patients likely to benefit from a lumbar stabilization exercise program. Physical Therapy 2007;87(3):313e25. Van Dillen LR, Sahrmann SA, Norton BJ, Caldwell CA, Fleming DA, McDonnell MK, et al. Reliability of physical examination items used for classification of patients with low back pain. Physical Therapy 1998;78(9):979e88. Wainner RS. Reliability of the clinical examination: how close is close enough? Journal of Orthopaedic & Sports Physical Therapy 2003;33(9):488e91. Wood KB, Popp CA, Transfeldt EE, Geissele AE. Radiographic evaluation of instability in spondylolisthesis. Spine 1994;19(15): 1697e703.
Available online at www.sciencedirect.com
Manual Therapy 14 (2009) 45e51 www.elsevier.com/math
Original article
Development of a headache-specific disability questionnaire for patients attending physiotherapy Ken Niere a,b,*, Anthony Quin a a
Musculoskeletal Research Centre, School of Physiotherapy, La Trobe University, Victoria 3086, Australia b Auburn Spinal Therapy Centre, Australia Received 13 June 2007; received in revised form 10 August 2007; accepted 24 September 2007
Abstract Headaches are relatively common, often leading to impaired function and decreased quality of life. Physiotherapists and other manual therapists treat patients with headaches when musculoskeletal dysfunction is the likely source or a significant contributing factor. The aim of this study was to develop a specific disability measure for use in a population of patients presenting for physiotherapy treatment of headache. Patients (N¼111) presenting to private physiotherapy practices in Victoria, Australia, for treatment of headaches completed a pre-existing, 16-item, headache disability questionnaire. Item responses were analysed separately to identify floor and ceiling effects and response rates, and by multivariate techniques to determine internal consistency and to identify unduly influential variables and underlying dimensions. Seven items from the original questionnaire were deleted due to significant floor effects, having low item-total correlations or after being judged unduly influential variables. The remaining nine items addressed the domains of pain severity, prevention of activity and reduction in ability to perform activities. The results of this study have led to the development of a valid and internally consistent questionnaire for measurement of the impact of headaches on patients receiving physiotherapy treatment. Further research is underway to examine the responsiveness and testeretest reliability of the questionnaire. Ó 2007 Elsevier Ltd. All rights reserved. Keywords: Headache; Outcome assessment; Disability; Physiotherapy
1. Introduction Physiotherapists treat patients presenting with headaches when musculoskeletal dysfunction is thought to be the cause or a contributing factor. Techniques are usually applied to the cervical and thoracic spines and commonly include manual therapy, therapeutic exercise, education, advice and electrotherapy (Grant and Niere, 2000). As with any physiotherapy technique or approach, valid, reliable and responsive outcome measures are essential to measure the effect of the intervention and if necessary, * Corresponding author. School of Physiotherapy, La Trobe Univers i t y , V i c t o r i a 3 0 8 6 , A u s t r a l i a . T e l . : þ6 1 3 9 4 7 9 5 8 5 7 , f a x : þ61 3 9479 5768. E-mail address:
[email protected] (K. Niere). 1356-689X/$ - see front matter Ó 2007 Elsevier Ltd. All rights reserved. doi:10.1016/j.math.2007.09.006
justify ongoing treatment. When considering outcome measures for physical treatment of headache in clinical trials and practice, the parameters of headache frequency, duration and intensity are often used (Niere and Robinson, 1997; Tuchin et al., 2000; Jull et al., 2002). In keeping with a patient centred approach to management, it is essential for the therapist to appreciate and be able to measure the effect that a patient’s headaches have on their quality of life. Cavallini et al. (1995) demonstrated that headache sufferers often experience a reduction in their functional capabilities during headache attacks. Their study indicated that subjects suffered from reduced motor performance, disturbed interpersonal relationships and feelings of inadequacy. Subjects also reported distress when attacks were imminent and reported disturbed relationships with family,
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friends and colleagues, often influencing the planning of their social lives. Other research has reinforced the findings of decreased quality of life in headache sufferers, including those with cervicogenic headache (Kryst and Scherl, 1994; Diener, 2001; Marcus, 2003). A number of measures have been designed to gauge headache-related disability. However, these have mostly related either to specific headache types such as migraine, or were developed within secondary referral headache clinics (Jacobsen et al., 1994; Stewart et al., 1998). An example of such a measure is the 16-item Headache Impact Questionnaire (HImQ) that was developed by an international, expert working group to measure the effects of headache, on quality of life (Stewart et al., 1998). From the HImQ, Stewart et al. (1999) developed a five-item Migraine Specific Assessment Scale (MIDAS) based on a 3-month time frame. The MIDAS items include: days missed from work or school because of headaches; days where productivity at work or school was reduced by at least half by headaches; days where headaches prevented household work; days where productivity in household work was reduced by at least half because of headaches and days where family, social or non-work (leisure) activities were missed because of headaches. The MIDAS has been shown to possess good internal consistency, reproducibility and validity in populations of patients with migraines (Stewart et al., 2001). Other studies (Solomon et al., 1994; Solomon, 1997) have used the SF36 (Ware and Sherbourne, 1992) to establish whether quality of life differs among headache diagnoses. They found that quality of life profiles for each of the common benign headache disorders (migraine, tensiontype, mixed and cluster) appear to be unique for the specific headache diagnosis. Therefore, it is unlikely that measures like the MIDAS would be suitable for measuring disability in patients with other headache types, although this has not been specifically tested. Physiotherapists treat musculoskeletal dysfunction in a variety of headache types including migraine, tensiontype headache and cervicogenic headache (Niere, 1998). Therefore, an instrument such as MIDAS may not be appropriate for measuring headache-related quality of life in all patients presenting for physiotherapy or indeed for health care practitioners who treat a general headache population. The aim of this study was to develop items for a headache-specific disability questionnaire suitable for patients receiving physiotherapy treatment for their headaches.
2. Method 2.1. Questionnaires A headache information form was adapted from a headache questionnaire developed by Watson and Trott
(1993). It included questions concerning age, sex and occupation of participants, length of headache history, precipitating and aggravating factors, accompanying sensations, medication use, pain description and area of headache. A further question to differentiate migraine from cervicogenic headache ascertained whether the headache was predominantly unilateral, and if so, whether it ever changed sides. The 16-item HImQ (Stewart et al., 1998) was used as an initial pool of questions with the aim of determining which of the items would be most suitable for measuring headache-related disability in patients attending physiotherapy. Items on the HImQ that required participants to indicate headache activity over a 3-month period were modified to take into account a 1-month time-frame. This was done to make the questionnaire applicable to patients who had a headache history of less than 3 months and to improve the accuracy of participant recall. 2.2. Recruitment Physiotherapists working in 45 private practices in Victoria, Australia, were invited to recruit participants for the study. Practices were selected to include a broad cross section of metropolitan and rural settings and a range of socio-economic backgrounds. Clinicians were instructed to invite up to five consecutive patients who satisfied the inclusion criteria to participate. The participants had to be at least 18 years of age, have presented for physiotherapy treatment of their headaches, have a history of at least one headache per month for more than 1 month and be fluent in written English. Exclusion criteria included current diagnosed psychiatric illness and contraindications to physiotherapy management such as suspected fractures, neoplastic disease, infection or other serious pathology. 2.3. Procedure Ethical approval for this study was granted by the La Trobe University Faculty of Health Sciences Human Ethics Committee. Once informed consent was granted, participants completed the headache information form and the HImQ without therapist assistance. The treating physiotherapist returned the completed questionnaires to the researchers in reply-paid envelopes. Responses to the headache information form and the items of the HImQ were entered into an SPSS data file. Provisional headache diagnosis was made for each participant by the senior researcher (KN) by completion of a standardised form using responses from the information form and the HImQ. The diagnosis form comprised a check list of the International Headache Society diagnostic criteria for migraine without aura, migraine with aura and tension type headache (IHS, 1988) and the diagnostic criteria for cervicogenic
K. Niere, A. Quin / Manual Therapy 14 (2009) 45e51
headache according to Sjaastad et al. (1998). Headaches not fulfilling the criteria for any of these diagnostic categories were classified as ‘‘other’’. Descriptive statistics were calculated to summarise demographic information. HImQ responses were analysed for the presence of floor or ceiling effects for each item. The criterion for a substantial and unacceptable floor or ceiling effect was if more than 50% of subjects selected the minimum or maximum response for an item (O’Mahoney et al., 1998; Wolinsky et al., 1998). In order to identify inter-item correlation and explore the factor structure and construct validity of the questionnaire, the HImQ data were examined as follows: A correlation matrix was generated using data gained from the HImQ. Confirmation of adequate inter-item correlation was provided by inspection of the correlation matrix. Item/total correlations for each variable were examined to determine the extent to which each variable correlated with the total score of all variables. Bartlett’s Test of Sphericity and the KaisereMeyere Olkin (KMO) measure of sampling adequacy were applied to test the sampling adequacy of the data for factor analysis. Rotation of the factors was performed to achieve a more interpretable factor matrix. Initially, the Varimax (orthogonal) rotation was selected. This keeps the factors uncorrelated. To further improve interpretability of the factor solution, an Oblimin (oblique) rotation was performed. Oblique rotation allows correlations between the factors. Cronbach’s alpha, a measure of the internal consistency, was calculated for the HImQ score based on the final items. Cronbach’s alpha is a measure analogous to a split-half reliability test, and ranges from 0 to 1.0. If any items were considered to be less acceptable for use in the questionnaire, repeat factor analyses were performed with and without the items to better find the combination of items that would yield a tool with acceptable factor structure and internal consistency.
47
10.4 (10.7) years, a mode of 5 years and a median of 6 years. Employment status as indicated by participants on the headache information form showed that 90 (81.1%) of the subjects worked full or part-time, 10 (9.0%) indicated home duties as their main occupation while eight were students, two were retired and one was unemployed. Average headache frequency was 10.7 (SD¼8.2) headaches per month with a median of eight headaches per month. Average (SD) intensity of the headaches was 6.9 (1.8) out of 10 with a median intensity of 7 out of 10 while reported headache duration ranged from 30 min to 2 weeks with an average (SD) of 29.6 (28.6) h and a median duration of 24 h. Diagnostic categories for the headaches experienced by the participants were: cervicogenic headache, N¼40 (36%); tension-type headache, N¼33 (30%); migraine without aura, 16 (14%) and migraine with aura, 8 (7%). Fourteen participants (13%) had headaches that did not fit the criteria for any of the above-mentioned diagnoses and were classified as ‘‘other’’. 3.2. Response rates Response rates for the individual HImQ items ranged from 95% to 100% with 14 of the 16 items rating at least 98%. These response rates support the face validity of the questionnaire items, indicating that participants who completed the questionnaires understood the questions and were able to choose an appropriate response. 3.3. Ceiling and floor effects There were no substantial and unacceptable ceiling effects observed for any of the items. However, 55% of respondents’ headaches had not kept them from work for at least half of the day in the previous month. Also, 50% of respondents indicated that they rarely or never experienced nausea with their headaches while a further 28 participants reported that nausea accompanied their headaches less than half the time. These findings were considered substantial, and unacceptable floor effects and the items related to presence of nausea and the number of days of missed work were deleted from the factor analysis.
3. Results 3.4. Itemetotal correlations 3.1. Demographic information and headache characteristics Of the 111 subjects who completed both the Headache Information Form and HImQ, 93 (83.8%) were female and 18 (16.2%) were male. The age of the participants ranged from 18 to 74 years with an average (SD) age of 38.3 (12.2) years. The length of history of headaches ranged from 5 weeks to 52 years with a mean (SD) of
Itemetotal correlations ranged from 0.31 to 0.68 except for headache frequency (0.17), time since the last headache (0.15) and headache duration (0.15). The low itemetotal correlations for these variables suggested that they poorly reflect the underlying construct of headache related disability. The negative itemetotal correlation for headache frequency indicated that headaches that occur with a greater frequency are less likely to be
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disabling than those that occur at a lesser frequency. The items for headache frequency, time since last headache and headache duration were not included in the factor analysis. 3.5. Factor analysis Inspection of the correlation matrix calculated for responses from the 16-item HImQ revealed that a substantial proportion (41%) of correlations was above 0.3, considered a criterion for good factor analysis (Fitzpatrick et al., 1998). There were no extremely high correlations (greater than 0.85) that may have indicated item redundancy. Further support of the adequate interitem correlations was provided by a value of 572 ( p<0.0001) for Bartlett’s Test of Sphericity and a KMO measure 0.78. The initial factor analysis resulted in a three-factor model that explained 69% of the variance in the data set. Final communalities (indicating the proportion of variance for each variable that is explained by the factors) were all above 0.6 except for the items relating to avoidance of light and sound (0.44) and the frequency of lying down to rest because of the headache (0.57). However, the rotated factor solution was not interpretable with the 11 retained items. It was hypothesised that the items on avoidance of light and sound and the frequency of lying down to rest were unduly influencing the factor solution. The factor analysis was repeated after deletion of these items. The three factor solution achieved with the remaining nine items explained 75.3% of the variance, resulted in communalities that were all greater that 0.6 and was interpretable in regard to headache related disability. It was felt that this result justified the exclusion of the items on avoidance of light and sound and frequency of lying down to rest. The final sorted factor matrix is displayed in Table 1. Inspection of Table 1 indicates that correlations between the nine HImQ items were best accounted for by three interrelated factors that were subsequently labelled to reflect their
Table 2 Labelled factors and items with loadings of greater than 0.7 in descending order of value Factor 1 Activity limitation
Factor 2 Activity prevention
Factor 3 Pain intensity
NWorkEff% WorkEff% ChoreEff% MissWork%
MissChoreN MissNWorkN LieDownN
PainSev% PainInt
interpreted dimensions. The labelled factors with correlated variables of greater than 0.7 are displayed in Table 2. 3.6. Inter-factor correlations The oblique rotation used for this factor analysis allows the factors to be correlated with each other. The strongest correlation was between factors 1 and 3 (r¼0.41). This positive correlation indicated that patients experiencing high degrees of activity limitation were also likely to suffer headaches of high pain intensity. Not surprisingly, the positive correlation between factors 1 and 2 (r¼0.39) indicated that patients with high degrees of activity limitation were also less likely to participate in these activities. Interestingly, the correlation between factors 2 and 3 was r¼0.10, indicating a weak relationship between level of participation restriction and headache pain intensity. 3.7. Proposed questionnaire A questionnaire incorporating the retained items has been proposed and is reproduced in Fig. 1. Cronbach’s alpha for items included in the final questionnaire was calculated at 0.80, indicating good internal consistency. Alpha values for individual factors were: activity limitation, 0.75; activity prevention, 0.82 and pain intensity, 0.70. To facilitate a practical scoring method for each item, an 11-point scale has been included. When HImQ
Table 1 Sorted factor matrix following oblique (Oblimin) rotation with correlations >0.70 in bold Item description
Abbreviation
Decreased efficiency in non-work activities Decreased ability to work or study Decreased efficiency in housework or chores Proportion of times where work is missed
NWorkEff% WorkEff% ChoreEff% MissWork%
Number of days where chores prevented Number of days non-work activities prevented Number of days where lie down >1 h Proportion of times when pain is severe Usual pain intensity
Factor 1
Factor 2
Factor 3
.89 .84 .81 .74
.06 .07 .07 .02
.12 .08 .01 .10
MissChoreN MissNWorkN LieDownN
.08 .12 .46
.92 .89 .81
.07 .08 .05
PainSev% PainInt
.04 .12
.01 .02
.93 .83
49
K. Niere, A. Quin / Manual Therapy 14 (2009) 45e51
HEADACHE DISABILITY QUESTIONNAIRE Name:…………………………………
Date:………/………./……….
Score
/ 90
Please read each question and circle the response that best applies to you 1. How would you rate the usual pain of your headache on a scale from 0 to 10? 0 NO PAIN
1
2
3
4
5
6
7
8
9
10
6
7
8
9
10
WORST PAIN
2. When you have headaches, how often is the pain severe? NEVER 0 1
ALWAYS 2
3
4
5
3. On how many days in the last month did you actually lie down for an hour or more because of your headaches? NONE 1-3 0 1
4-6
7-9
10-12
13-15
16-18
19-21
22-24
25-27
28-31
2
3
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EVERY DAY
4. When you have a headache, how often do you miss work or school for all or part of the day? NEVER 0 1
ALWAYS 2
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8
9
10
5. When you have a headache while you work (or school), how much is your ability to work reduced? NOT 0 1 REDUCED
2
3
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7
8
9
10
UNABLE TO WORK
6. How many days in the last month have you been kept from performing housework or chores for at least half of the day because of your headaches? NONE 1-3 0 1
4-6
7-9
10-12
13-15
16-18
19-21
22-24
25-27
28-31
2
3
4
5
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EVERY DAY
7. When you have a headache, how much is your ability to perform housework or chores reduced? NOT 0 1 REDUCED
2
3
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5
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7
8
9
10
UNABLE TO PERFORM
8. How many days in the last month have you been kept from non-work activities (family, social or recreational) because of your headaches? NONE 1-3 0 1
4-6
7-9
10-12
13-15
16-18
19-21
22-24
25-27
28-31
2
3
4
5
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EVERY DAY
9. When you have a headache, how much is your ability to engage in non-work activities (family, social or recreational) reduced? NOT 0 1 REDUCED
2
3
4
5
6
7
8
9
10
UNABLE TO PERFORM
Fig. 1. The headache disability questionnaire.
scores for the nine items were converted to a 0e10 scale, total scores for the proposed Headache Disability Questionnaire (HDQ) ranged from 0 to 74 out of 90, with an interquartile range of 25.0e41.8. The mean and median HDQ values were 34.89 and 34.50, respectively (SD¼12.66).
4. Discussion The results of this study have led to the development of a nine-item questionnaire (Fig. 1) that we believe measures headache-related disability experienced by patients receiving physiotherapy treatment. The proposed
50
K. Niere, A. Quin / Manual Therapy 14 (2009) 45e51
HDQ has appropriate construct validity, reflected by three related factors that encompass the domains of activity prevention, activity restriction and pain intensity. It also shows good internal consistency (Cronbach’s alpha¼0.80), indicating that the components (items) contribute evenly to the measurement of one broad construct (headache-related disability). In the proposed format, the HDQ would be relatively quick to complete, having only nine items and easy to score with a 0e10 scale for each item. High response rates for the items imply acceptability in the population studied. The items selected for the HDQ are different from the five items on the MIDAS developed by Stewart et al. (1999). Both questionnaires have four items in common: days missed from non-work or school duties, days missed from housework or chores and days where the efficiency of housework/chores and non-work/school was limited (two items). While in the MIDAS, limitation of activity imposed by the headache is measured in terms of days where efficiency is reduced by more than 50% we have preferred to use an 11-point (0e10) scale of percentages from 0% to 100%. We have also used this principle for the items relating to decreased efficiency in work/study, how often work or school is missed and the proportion of times when pain is severe. Most participants (55%) in this study did not miss work or school due to their headaches and the mean number of missed work days over 1 month in this study was only 1.6 days. These findings for missed work/study frequency indicate that most general headache sufferers do not miss work/study days due to their headaches. Rather, they attempt to function on the job (or at school) with considerably reduced effectiveness and a subsequent degree of functional limitation. In this and previous studies (Stewart et al., 1998, 1999), headache sufferers were more inclined to miss chores and non-work (family, social, and leisure) activities than work/study related activities. The items measuring headache frequency and headache duration were not included in the HDQ because of low correlation with other items, and low itemetotal correlations. Deletion of items does not imply insignificance or irrelevance as measures of headache outcome. Rather, improved factor interpretability following item deletion in this study meant that a particular variable may not have been the most suitable question for inclusion in an instrument for measuring headache-related disability in the population studied. 4.1. Limitations The results cannot be generalised to a younger population as the study did not include either children or adolescents. Also, results can only be generalised to headache patients attending private physiotherapy practices. It is not known whether patients in public
and private hospital settings, rehabilitation centres or community health centres would have given similar responses. The findings can be generalised to the general headache population, but not necessarily to specific headache groups, such as tension-type headache, migraine or cervicogenic headache. The current research was limited to patients fluent in written and spoken English. The ease and accuracy with which those with poorer English comprehension skills would have completed the questionnaire was not addressed. A potential limitation of factor analysis as used in this study is that the factors extracted can only reflect the data that is included in the model. For example, if pain intensity measures had not been part of the initial 16 HImQ items, the pain intensity factor would not have been defined. 4.2. Clinical relevance and implications of findings Questionnaires are a quick and practical way of gaining relatively accurate, self-reported data about quality of life limitations. The proposed HDQ (Fig. 1), based on the nine items identified in this study, could be an appropriate instrument for clinical use due to its simplicity in administration, anticipated short completion time and likely ease of scoring. The appropriateness of the individual items was demonstrated by high response rates, at least in the format of the HImQ, further supporting the potential usefulness of this questionnaire in the clinical setting. The unidimensional parameters of headache intensity, frequency and duration are widely used in the clinical setting as outcomes by which the effectiveness of headache treatment is gauged. A previous study (Niere, 1997) found that of 154 subjects presenting as new patients to private physiotherapy practices for treatment of headache, 66% nominated reduction of headache frequency as the most important indicator of treatment success, followed by reduced intensity (21%), improved function (8%), and decreased duration (5%). In this study, headache frequency and duration did not substantially reflect the broader construct of headache impact. However, it is recommended that these parameters be measured individually, in addition to the nine-item HDQ score. 4.3. Future research It is recommended that the testeretest reliability (reproducibility) and responsiveness (sensitivity to change) of the HDQ be determined before it can be used with confidence in the clinical setting. It should also be noted that the factor structure and internal consistency were not analysed using the scoring system of the proposed HDQ. Confirmatory factor analysis on a new data set would be useful to confirm the factor structure of the proposed HDQ. Head to head comparison of HDQ properties and scores with other measures such as the
K. Niere, A. Quin / Manual Therapy 14 (2009) 45e51
MIDAS would be useful in gauging specificity and criterion-related validity. It would also be useful to know the minimum level of detectable change within the HDQ score and how this relates to the minimum clinically important difference. Studies are currently underway to establish these properties. Further studies could analyse populations in different settings (hospital outpatients, community health centres) and whether the HDQ is likely to be useful for assessing headache-related disability in adolescents and children.
5. Conclusion This study has led to the development of a nine-item questionnaire that measures the construct of headacherelated disability in a population of patients receiving physiotherapy treatment for their headaches. The proposed HDQ combines items that measure headache intensity, activity prevention and degree of activity restriction. The results of this study indicate that the HDQ has good content and construct validity and is likely to be easy to administer and score when used on a clinical population. Further psychometric testing is necessary before the HDQ can be confidently recommended for clinical use.
References Cavallini A, Micieli G, Bussone G, Rossi F, Nappi G. Headache and quality of life. Headache 1995;35:29e35. Diener I. The impact of cervicogenic headache on patients attending a private physiotherapy practice in Cape Town. South African Journal of Physiotherapy 2001;57:35e9. Fitzpatrick R, Davey C, Buxton MJ, Jones DR. Evaluating patientbased outcome measures for use in clinical trials. Health Technology Assessment 1998;2:14. Grant T, Niere K. Techniques used by manipulative physiotherapists in the management of headaches. Australian Journal of Physiotherapy 2000;46(4):215e22. International Headache Society, Headache, Classification, Committee. Classification and diagnostic criteria for headache disorders, cranial neuralgias and facial pain. Cephalalgia 1988;8(7S):1e96. Jacobsen G, Ramadan N, Aggarwal S, Newman C. The Henry Ford Hospital headache disability inventory (HDI). Neurology 1994;44:837e42.
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Jull G, Trott P, Potter H, Zito G, Niere K, Shirley D, et al. A randomized controlled trial of exercise and manipulative therapy for cervicogenic headache. Spine 2002;27:1835e43. Kryst S, Scherl E. A population-based survey of the social and personal impact of headache. Headache 1994;34(6):344e50. Marcus D. Disability and chronic posttraumatic headache. Headache 2003;43:117e21. Niere K. Expectations of physiotherapy treatment in headache patients. In: Gerrard B, editor. Focusing ahead: Proceedings of the 10th biennial conference of the Manipulative Physiotherpists’ Association of Australia. Melbourne: MPAA Publishers; 1997. p. 136e7. Niere K. Can characteristics of benign headache predict manipulative physiotherapy treatment outcome? Australian Journal of Physiotherapy 1998;44(2):87e93. Niere KR, Robinson PM. Determination of manipulative physiotherapy treatment outcome in headache patients. Manual Therapy 1997;2:199e205. O’Mahoney PG, Rodgers H, Thomson RG, Dobson R, James OFW. Is the SF-36 suitable for assessing health status of older stroke patients? Age and Ageing 1998;27:19e22. Sjaastad O, Fredriksen T, Pfaffenrath V. Cervicogenic headache: diagnostic criteria. Headache 1998;38(6):442e5. Solomon G. Evolution of the measurement of quality of life in migraine. Neurology 1997;48(Suppl. 3):S10e5. Solomon G, Skobieranda F, Gragg L. Does quality of life differ among headache diagnoses? Analysis using the medical outcomes study instrument. Headache 1994;34:143e7. Stewart WF, Lipton RB, Simon D, Von Korff M, Liberman J. Reliability of an illness severity measure for headache in a population sample of migraine sufferers. Cephalalgia 1998; 18(1):44e51. Stewart WF, Lipton RB, Kolodner K, Liberman J, Sawyer J. Reliability of the migraine disability assessment score in a population-based sample of headache sufferers. Cephalalgia 1999; 19:107e14. Stewart WF, Lipton RB, Dowson AJ, Sawyer J. Development and testing of the migraine disability assessment (MIDAS) questionnaire to assess headache-related disability. Neurology 2001;56:S20e8. Tuchin P, Pollard H, Bonello R. A randomized controlled trial of chiropractic spinal manipulative therapy for migraine. Journal of Manipulative and Physiological Therapeutics 2000;23(2):91e5. Ware JE, Sherbourne CD. The MOS 36-item short-form health survey (SF-36). I. Conceptual framework and item selection. Medical Care 1992;30:473e83. Watson D, Trott P. Cervical headache: an investigation of natural head posture and upper cervical flexor muscle performance. Cephalalgia 1993;13(4):272e84. Wolinsky FD, Wyrwich KW, Nienaber NA, Tierney WM. Generic versus disease-specific health status measures. An example using coronary artery disease and congestive heart failure. Evaluation and the Health Professions 1998;21:216e42.
Available online at www.sciencedirect.com
Manual Therapy 14 (2009) 52e60 www.elsevier.com/math
Original article
Further examination of modifying patient-preferred movement and alignment strategies in patients with low back pain during symptomatic tests* Linda R. Van Dillen a,*, Katrina S. Maluf b,1, Shirley A. Sahrmann c a
Program in Physical Therapy, Washington University School of Medicine, 4444 Forest Park Ave., Campus Box 8502, St. Louis, MO 63108, USA b Department of Rehabilitation Medicine, University of Iowa, USA c Departments of Neurobiology, Cell Biology and Physiology, Program in Physical Therapy, Washington University School of Medicine, St. Louis, MO, USA Received 9 March 2006; received in revised form 13 August 2007; accepted 14 September 2007
Abstract Our purpose was to examine the effect of modifying symptomatic movement and alignment tests in a sample of people with LBP referred to physical therapy. Fifty-one patients (19 males, 32 females; mean age 3710.59 yr) with LBP and a mean Oswestry Disability Index score of 3418% were examined. The examination included 28 primary tests in which patients used their preferred movement or alignment strategy and reported symptoms. Symptomatic tests were followed by a secondary test in which the patient’s strategy was standardly modified to correct the spinal alignment or movement that occurred with the primary test. Symptoms and directions of movement or alignment modified were recorded. For 82% of the secondary tests, the majority of the patients’ symptoms improved. For 54% of the secondary tests, some patients required modification of more than one direction of movement or alignment to eliminate symptoms. The findings suggest that the modifications described are generalizable across a number of tests with a moderately involved group of patients, and for individual tests there is variability in the numbers and directions of movements or alignments that appear to contribute to symptoms. Information obtained from the modifications is important because it can be used to confirm the patient’s LBP classification and, within the context of the examination, immediately be used to teach the patient strategies to change movements and positions that appear to be contributing to his LBP. Ó 2007 Elsevier Ltd. All rights reserved. Keywords: Low back pain; Rehabilitation
1. Introduction Examinations to identify the mechanical factors contributing to a patient’s low back pain (LBP) often * The study was conducted in St. Louis, Missouri at the Program in Physical Therapy, Washington University School of Medicine. Presented in part, at the Combined Sections Meeting of the American Physical Therapy Association, Tampa, FL, February 13, 2003. * Corresponding author. Tel.: þ1 314 286 1427; fax: þ1 314 286 1410. E-mail address:
[email protected] (L.R. Van Dillen). 1 Affiliation at time of study: Program in Physical Therapy, Washington University School of Medicine, USA.
1356-689X/$ - see front matter Ó 2007 Elsevier Ltd. All rights reserved. doi:10.1016/j.math.2007.09.012
include active movement tests and alignment tests in which symptoms are assessed. Judgments of impairments are also often made. Traditionally, such examinations have focused on symptoms with a variety of trunk movements and positions including (1) single (Cyriax, 1982; Maitland and Edwards, 1986; Cailliet, 1988; Spratt et al., 1990; Moffroid et al.,1994; Delitto et al., 1995; Van Dillen et al., 1998; McKenzie and May, 2003a) and repeated trunk movements (Spratt et al., 1990; Delitto et al., 1995; McKenzie and May, 2003a), (2) combined trunk movements with and without overpressure (Maitland, 1986; Edwards, 1994) or (3)
L.R. Van Dillen et al. / Manual Therapy 14 (2009) 52e60
sustained end-range trunk positions (Moffroid et al., 1994; Delitto et al., 1995; McKenzie and May, 2003a). Some of the examinations are used to classify the LBP (Moffroid et al., 1994; Delitto et al., 1995; Sahrmann, 2002; McKenzie and May, 2003b). The overall goal of testing is to identify the trunk movements and alignments that increase or decrease the patient’s symptoms. Based on the findings various treatments may be implemented with the goal of improving the LBP problem. Work has been ongoing to examine properties of one of these examinations (Van Dillen et al., 1998) used clinically to classify LBP problems (Sahrmann, 2002). Briefly, the examination includes primary tests of trunk movements and alignments as well as limb movements. Symptoms are assessed and impairments are identified. Each test is presumed to be associated with the direction(s) of flexion, extension, rotation, rotation and extension or rotation and flexion. The patient performs a primary test once using his preferred strategy and reports symptoms. Standardized modifications for a subset (N¼9) of primary tests were initially included based on the observation that symptoms often decrease by modifying how the patient moves or aligns the lumbar region during tests and functional activities. These are referred to as secondary tests. Overall, modifications involve (1) restricting movement of the lumbar region while encouraging movement in other regions, for example, the thoracic region or hip joint or (2) positioning the lumbar region in as close to a neutral alignment as possible (Adams et al., 2002; McGill, 2002). If a primary test increases symptoms the associated secondary test immediately follows. Symptoms are compared to those with the primary test. A patient’s LBP is classified based on the direction(s) of alignment and movement most consistently associated with a change in symptoms and impairments across the examination. A change in symptoms in this case refers to symptom behavior both with primary tests and with secondary tests. For example, a patient might report (1) an increase in symptoms with the flexion-related primary tests, (2) a decrease in symptoms with the associated flexion-related secondary tests, and (3) no change in symptoms with tests associated with other directions of movement and alignment. The patient’s LBP classification would be lumbar flexion. Proposed LBP classifications include lumbar (1) flexion, (2) extension, (3) rotation, (4) rotation with flexion, and (5) rotation with extension (Sahrmann, 2002). A preliminary study was conducted to examine whether the subset of secondary tests actually resulted in a decrease in symptoms. Overall, the majority of patients reported a decrease with eight of nine tests (Van Dillen et al., 2003a). These findings were important because they suggested that systematically modifying symptomatic tests could provide a clinical method for identifying the specific directions of movement and alignment that appear to contribute to the patient’s
53
LBP. Such data, therefore, provides confirmatory information for classifying the LBP. Although these findings were encouraging, the effects were examined in only nine secondary tests. However, to obtain an adequate sample of tests of the directions of movement and alignment proposed to characterize different LBP subgroups (Sahrmann, 2002; Van Dillen et al., 2003b), we currently include 28 primary tests. We also know that patients vary in the types and numbers of primary tests that are symptom-provoking (Van Dillen et al., 2001a, 2003b). For example, a patient with a rotation with flexion problem may report symptoms with only 30% of flexion-related tests and 25% of rotation-related tests. Thus, in order to confirm a patient’s classification we considered it essential to have secondary tests defined for each primary test. During our preliminary study we also did not document the (1) specific directions of movement and alignment modified or (2) extent of symptom change (decreased versus (vs.) eliminated). Such information would not only provide more specific confirmatory information, the consistency of responses could potentially lend insight into a patient’s prognosis for rehabilitation. Finally, only 55% of our sample was recruited from clinics and many had already received treatment for their current LBP. The generalizability of the findings to clinically based, untreated patients, therefore, was limited. For these reasons we chose to examine patients with LBP on their first clinical visit using a revised examination that included secondary tests for all primary tests. We also recorded the specific directions of movement or alignment modified and extent of change with each test. The primary purposes of the current study were to examine (1) whether our preliminary findings would generalize to a greater number of secondary tests in a more involved group of patients than the prior sample, (2) the percentages of patients who reported a decrease vs. elimination of symptoms, and (3) the directions of modifications with each test that resulted in an elimination of symptoms. We hypothesized that (1) the majority of patients would report a decrease or elimination of symptoms with each of the secondary tests and (2) some patients would require more than one direction to be modified with individual secondary tests to eliminate symptoms.
2. Methods 2.1. Subjects Subjects were recruited from consecutive patients with a LBP-related diagnosis referred for treatment to a university-based outpatient physical therapy clinic in the St. Louis metropolitan area. At their initial visit, all patients with a LBP-related medical diagnosis on the physician’s referral were given a self-report form
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L.R. Van Dillen et al. / Manual Therapy 14 (2009) 52e60
with a list of the exclusion criteria. The patient was eliminated if he answered positively to any of the criteria. Patients between 18 and 75 years of age who had symptoms related to a LBP problem in either the region of the lower back, proximal lower extremity (LE) or distal LE (Spitzer et al., 1987) were eligible for inclusion in the study. Subjects were excluded if the patient reported, or had a diagnosis on their referral of spinal stenosis, osteoporosis, spondylolisthesis, spinal fusion, rheumatoid arthritis, and ankylosing spondylitis. Subjects were also excluded in the case of severe kyphosis or scoliosis, neurological disease that required hospitalization, current treatment for cancer, or had current medical complications involving the spine. All patients who met the criteria read and signed an informed consent approved by the Washington University Medical School Human Studies Committee before participating. Table 1 provides the sample characteristics of the 51 patients (37% male, 63% female) who participated. 2.2. Examination items The items of interest were the primary and secondary tests from the standardized clinical examination (Van Dillen et al., 1998). The primary tests included 7 tests of trunk alignment, 5 tests of trunk movement, and 16 tests of limb movements (eight/side). Secondary tests were defined for each primary test (see Appendix A). For each secondary test the examiner would give verbal instructions and physical assistance. Directions of movement Table 1 Characteristics of study sample Characteristic
Value
Mean age in years (S.D.) Mean height in centimeters (S.D.) Mean weight in kilograms (S.D.) Mean pain intensity rating over previous week (Bolton, 1999) (0e10) (S.D.) Location of current symptomsa (Spitzer et al., 1987) Low back only Low back/proximal lower extremity (LE) Low back/distal LE Low back/proximal LE/distal LE History of previous episode of LBP Mean Oswestry disability questionnaire scores (Fairbank, et al., 1980) (S.D.) LBP categoryb Acute Subacute Chronic
36 (10.59) 172.15 (10.62) 88.02 (25.66) 5.29 (2.21)
Fig. 1. Example of modification of right side lying during a secondary test of alignment.
or alignment modified were recorded (see Appendix A). Figs. 1 and 2 provide examples of modifying a trunk alignment and a limb movement, respectively. The possible symptom responses included increased, same, decreased or eliminated (Van Dillen et al., 2001b). Appendix B provides the operational definitions. Inter-rater reliability of examiners performing 28 of the 56 tests in the current study has been reported (Van Dillen et al., 1998). Kappa coefficients for some items were attenuated due to low prevalence rates (Feinstein and Cicchetti, 1990). Using a testeretest design, reliability of the two examiners was also examined performing tests in the current study on 7 patients with LBP. Percent agreement values for assessment of symptoms for two of the secondary tests, modification of forward bend and of flexed sitting were 70%. Percent agreement values for the remaining tests ranged from 80% to 100%. Percent agreement values for the
24 (47%) 10 (20%) 2 (4%) 15 (29%) 33 (65%) 32 (18%)
2 (4%) 19 (38%) 30 (58%)
a Definitions for location of symptoms from the Quebec task force on spinal disorders (Spitzer et al., 1987). Low back: region from T12 to gluteal fold; proximal LE: region from gluteal fold to knee; distal LE: below knee. b Definitions for LBP categories from the Quebec task force on spinal disorders (Spitzer et al., 1987). Acute: onset of symptoms <7 days; Subacute: onset of symptoms 7 dayse7 weeks; chronic: onset of symptoms >7 weeks.
Fig. 2. Example of modification of hip lateral rotation in prone during a secondary test of movement.
L.R. Van Dillen et al. / Manual Therapy 14 (2009) 52e60
movement and alignment judgments ranged from 65% to 100%. Additional reliability statistics were not calculated due to sample size (Cicchetti and Sparrow, 1981). 2.3. Procedures Each patient was examined on the first visit to the clinic by one of two trained physical therapists. The therapists were 42 and 25 years of age. One therapist had 17 years of experience and the other therapist had just completed her Master’s degree in Physical Therapy. For each patient the sequence of test positions (standing, sitting, supine, side lying, prone, quadruped) was randomized to control for order effects. 2.4. Data analysis Data analysis was performed using Systat version 10.2 for Windows (SPSS, Inc., Chicago, IL). Descriptive statistics were calculated for patient characteristics and diagnoses. Frequencies and percentages of symptom responses for each secondary test were calculated for only those patients who reported an increase in symptoms with the corresponding primary test. For each secondary test a c2 goodness-of-fit analysis then was performed on the frequencies of responses to examine if the percentages of patients in each of 3 response categories (decreased, same, increased) were different. The decreased response for this analysis included patients with a decrease or an elimination of symptoms. To examine how much symptoms improved, a oneway analysis of variance (ANOVA) was conducted on the percentage of patients with a decrease vs. elimination of symptoms. Finally, to examine if more than one direction of movement or alignment had to be modified to eliminate symptoms, frequencies and percentages of the directions modified were calculated. These statistics were calculated for each secondary test for only patients who reported an elimination of symptoms. The probability level for all significance testing was set at the P#.05 level.
3. Results
55
3.2. Exceptions Three percent (49/1428) of the total responses for the primary tests were not obtained. Nine patients were unable to provide a response for at least one of the primary tests. Five (56%) patients did not schedule sufficient time, 3 had neck, shoulder, or knee pain that limited some positions and one could not assume quadruped due to obesity. 3.3. Secondary tests Appendix A includes a list of the secondary tests and directions of lumbar region movement or alignment that potentially would need to be modified to decrease symptoms. Table 2 lists the secondary tests and the percentages who reported a decrease in symptoms with each secondary test. Overall, all 51 patients reported a decrease or elimination of symptoms with one or more of the 28 tests. The mean percentage of patients who reported a decrease in symptoms was 8410% with a range of 100e58%. The majority of patients reported a decrease in symptoms for 23 (82%) of the 28 secondary tests (all comparisons P#.05). The five tests in which the majority did not report a decrease in symptoms included 2 trunk alignments (left side lying and quadruped) and 3 right limb movement tests (hip abduction/lateral rotation, hip lateral rotation and shoulder flexion in quadruped). For each of the secondary tests some patients reported a decrease and some reported an elimination of symptoms. On average, 523% reported a decrease in symptoms and 484% reported an elimination of symptoms (F¼0.55, P¼0.460). For 6 of the 7 trunk alignment tests (86%) all patients required only one direction of alignment modified. One patient required modification of 2 directions of alignment with left side lying. For all 5 of the trunk movement tests (100%) some patients required modification of 2 directions of movement. Finally, for 9 of the 16 limb movement tests (56%) some patients required modification of 2 directions of movement. These tests included knee extension in sitting (bilateral), hip and knee flexion in supine (bilateral), knee flexion in prone (bilateral), hip extension in prone (bilateral), and right arm lift in quadruped.
3.1. Patient characteristics Descriptive statistics for patient characteristics are summarized in Table 1. The majority of patients (64%) were referred with a diagnosis of LBP. Ten percent were diagnosed as a lumbar sprain or strain, 8% as lumbar radiculopathy and 8% as lumbar segmental dysfunction. Four percent were diagnosed as degenerative disc or joint disease and another 4% were myofascial pain. Finally, 2% were referred with a diagnosis of lumbago.
4. Discussion 4.1. Primary findings Our purpose was to examine, in patients at their initial physical therapy visit, the effects of standardly modifying examination tests used to classify LBP. The findings from the current study extend the findings from our preliminary work (Van Dillen et al., 2003a). The modifications can be
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L.R. Van Dillen et al. / Manual Therapy 14 (2009) 52e60
Table 2 Percentages of patients who reported a decreasea in symptoms with each secondary testb Test categoryc
Secondary test
Trunk alignment
Sitting: flexion Sitting: extension Supine Side lying Prone Quadruped
Percentage reporting decreased symptoms (%) Right
Trunk movement
Limb movement
Standing: forward bend Standing: return from forward bend Standing: lateral bend Quadruped: rock back Sitting: knee extension Supine: hip and knee flexion Supine: hip abduction and lateral rotation Prone: knee flexion Prone: hip lateral rotation Prone: hip medial rotation Prone: hip extension Quadruped: shoulder flexion
Left
Other 75 88 94
73
58d 78 75d 90 90
96
81 83
83 81 75d 85 71d 93 95 71d
91 73 100 100 86 86 89 80
a
Decreased responses include patients who reported a decrease or an elimination of symptoms when the primary test was modified. Secondary test findings from those who had an increase in symptoms with the corresponding primary test. Modifications include (1) aligning the lumbar region in as close to neutral as possible (Adams and Dolan, 1995; McGill, 2002) or (2) restricting lumbar region movement and encouraging movement in other regions, e.g., hip joint, thoracic region. c There were three categories of tests: (1) tests of trunk alignment, (2) tests of trunk movement, and (3) tests of limb movements. d Indicates no difference between those reporting decreased vs. same for symptoms with the secondary test. For all other secondary tests, the majority of patients reported a decrease in symptoms (P#.05). b
applied to all of the primary tests and to a clinically based group of patients with higher levels of symptoms and LBPrelated disability than our original study (Table 1). A significant number of patients reported an improvement in their symptoms with 71% of the alignment tests and 86% of the movement tests (Table 2). On average, patients’ symptoms were decreased 50% of the time and eliminated 50% of the time with the secondary tests. Finally, for individual tests we identified the number of directions of movements or alignments required to eliminate symptoms. These findings are important because (1) they suggest it is possible to obtain immediate information about whether the patient’s symptoms can be changed by direction-specific modifications, (2) many patients improve with the modifications, and (3) some patients will require modification of more than one direction of movement or alignment to eliminate symptoms. The specific movement and alignment information and response to modifications is essential for confirming the patient’s direction-specific LBP classification. Classifying LBP problems is important for direction of treatment and prognosis (Spitzer et al., 1987). 4.2. Clinical relevance The findings from the described methods are used to assist in classifying the movement-system aspect of
a patient’s LBP problem (Sahrmann, 2002). The findings are of particular relevance because tests are given more significance in the decision-making process if a primary test produces increased symptoms and the associated secondary test produces decreased symptoms. Thus, each modification provides the clinician with immediate and confirmatory information about the specific direction(s) of movement or alignment related to the patient’s LBP. Because patients vary in the type and number of tests that are symptomatic, it is essential to have methods that confirm the specific movements and alignments contributing to the patient’s symptoms for each examination test to effectively classify the LBP. The classification assigned describes the direction(s) of movement and alignment that are most consistently associated with changes in symptoms and impairments identified across the examination. Such changes in symptom behavior are considered both during primary and secondary tests associated with a particular direction of movement or alignment. For example, an increase in symptoms with primary tests associated with lumbar region flexion, a decrease or elimination of symptoms during the associated secondary tests and no change in symptoms with primary tests associated with other directions of movement and alignment would result in a flexion-related classification. Considering the classification identifies the movement-system contribution to
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the LBP problem it can then be used to direct treatment. Treatment includes (1) education about how generalizing the identified movement and alignment strategies across multiple activities potentially contributes to acceleration of lumbar region tissue stress and symptoms (Mueller and Maluf, 2002) and (2) modification of strategies through retraining of functional activities and exercise. For example, a patient classified as lumbar flexion would be educated about his tendency to flex the lumbar region with multiple functional activities. The patient would be educated about how the repetitive use of flexion movements and alignments across the day potentially contributes to increased lumbar region tissue stress and symptoms, particularly because they are performed in the same direction. Each of the patient’s symptom-provoking functional activities, as well as those frequently repeated throughout the day, then would be observed, analyzed, and modified. Emphasis would be placed on modifying the activities so the patient could accomplish the activities without the use of lumbar flexion. Finally, secondary test modifications that resulted in a decrease or elimination of symptoms with primary tests from the examination would be prescribed as exercises. The secondary test responses are also considered to be related to the patient’s prognosis in two ways. First, based on clinical observation, it appears that the course of the different LBP classifications identified, in part, with the secondary tests, may differ. Knowledge of prognoses for different classifications will assist the clinician in treatment and goal setting. Second, if the patient’s modifications are readily implemented and improve symptoms the prognosis for treatment is likely to be good. Thus far, descriptive and pilot work examining classification-based treatment based, in part, on the associated modifications, has resulted in positive shortand long-term outcomes (Maluf et al., 2000; Harris Hayes et al., 2005; Van Dillen et al., 2005; Van Dillen and Sahrmann, 2006). Future randomized clinical trials, however, comparing classification-based treatment to other treatments are required to fully test these preliminary outcomes. 4.3. Prior literature McKenzie described a symptom assessment method in which the patient performs single and repeated endrange spinal movements or assumes sustained end-range spinal alignments (McKenzie and May, 2003a). The findings from testing are used for LBP classification to assist in treatment and prognosis. Similar to the current study, Donelson et al. examined patients’ responses to McKenzie’s testing within a single session in patients with varying levels of acuity and symptom location (Donelson et al., 1991). The authors reported that more subjects’ symptoms improved with repeated extension than
57
repeated flexion movements. Because we do not perform repeated spinal movements for symptom assessment the current findings cannot be directly compared to the Donelson et al. study. Both studies, however, suggest that the majority of patients appear to positively respond to the described methods of symptom testing. Future studies need to compare the characteristics of patients who respond positively to one, both, or neither of the symptom assessment methods to determine the optimal methods to be applied to different patient types. The McKenzie method appears applicable to a number of people with LBP (Fritz et al., 2003; Long et al., 2004), and centralization has been related to a good prognosis (Donelson et al., 1990; Long, 1995). There is data, however, to suggest that not all patients will respond systematically to the described symptom testing (Fritz & George, 2000; Fritz et al., 2003; Long et al., 2004) and a suggestion that treatment effects based on results of the McKenzie symptom testing are not always consistent (Delitto et al., 1995). Considering the majority of people in the current study improved with the tests examined, the described methods could provide an alternative method for those who do not systematically respond to McKenzie methods. 4.4. Acuity and location of symptoms We did not examine differential effects of the secondary test methods based on acuity or location of symptoms. These were not performed because currently there is no theoretical basis to suggest that the results of individual secondary tests or the different classifications we identify based, in part, on the secondary test results would differ based on these variables. The primary directions of movement and alignment that are considered to contribute to a patient’s LBP are considered to be the same irrespective of acuity or symptom location. For example, a patient classified with lumbar rotation with flexion (1) may seek treatment in the acute, subacute or chronic stage and (2) may or may not have symptoms that extend to the proximal or distal LE. Based on pilot work and clinical observation we do know that, within a patient, what may vary based on acuity or location is the (1) number of primary tests that are symptomatic and (2) extent of change in symptoms (decreased vs. eliminated) with secondary tests (unpublished data). 4.5. Limitations One potential limitation is that not all patients completed all 28 primary tests (Table A1). Only four patients, however, were unable to perform some of the tests because of their LBP problem (Table A1). Because of the number and inter-relationships among the tests (Van Dillen et al., 2003b), missing responses to some of the tests should not preclude classification. A second
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potential limitation is that only a minimal amount of testing has been done on the reliability of clinicians inexperienced in the use of the symptom testing and examination (Turner et al., 2005). The findings from the current study, therefore, may not be easily replicated. Future studies could focus on training inexperienced clinicians to determine if similar changes in symptoms can be obtained. A third limitation is that the prognostic value of the findings from the symptom testing is speculative at this point in time. The data currently available are case reports of people with LBP who responded positively to the symptom testing and were treated based on results of the testing and their LBP classification, and a pilot study of outcomes of people treated based on their LBP classification compared to an untreated group of people with LBP (Maluf et al., 2000; Harris Hayes et al., 2005; Van Dillen et al., 2005; Van Dillen and Sahrmann, 2006). Longitudinal studies of outcomes of patients who do and do not respond positively to the symptom testing are indicated. A fourth limitation is that the symptom testing, classification system and treatment based on the results of symptom testing are based on a proposed conceptual model for LBP that is not fully tested. Work is ongoing to test assumptions of the proposed LBP model (Van Dillen et al., 2001a, 2003a, 2005; Gombatto et al., 2006; Van Dillen and Sahrmann, 2006; Gombatto et al., 2007; Scholtes and Van Dillen, in press) and to test the reliability and validity of the classification system based on the proposed model (Van Dillen et al., 1998,2003b; Maluf et al., 2000; Norton et al., 2004; Harris Hayes et al., 2005; Turner et al., 2005; Van Dillen et al., 2005; Van Dillen and Sahrmann, 2006). Considering the status of testing, the validity of the assumptions underlying the effects of the described symptom testing is still tentative. A fifth limitation is the current study is focused on only some of the variables that would assist in understanding and identifying the various contributions to the patient’s LBP problem. Consistent with the biopsychosocial model (Waddell, 1998), information about several other variables (history, self-report, laboratory measures) are essential to designing treatment and prognosing. The variables focused on in the current study provide insight only into some of the movement-system variables potentially contributing to the LBP problem. A final limitation is that we do not know if any of the patients in our sample demonstrated high levels of fear-avoidance behavior (Waddell et al., 1993). We would assume, however, that if this was an issue a patient would avoid performing any tests that increase symptoms. The four patients who did not perform a few of the tests because of their LBP did perform other tests that increased symptoms. Future work could examine how people who display different levels of fear-avoidance behavior respond during the tests described.
5. Conclusions The findings suggest that the modifications are generalizable across a number of tests and to a clinically based sample of patients who have not been treated for their current LBP, and result in a decrease in symptoms in the majority of patients. Additionally, for many tests there is variability in the numbers of movements or alignments that appear to contribute to symptoms and that would need to be modified to improve symptoms. Information obtained from the modifications is important because it can be used to assist in confirming a patient’s LBP classification and thus, assist in directing treatment and prognosis.
Acknowledgments The authors wish to acknowledge Tom Susco, A.T.C, D.P.T. for his assistance in data processing and analysis and Kate Crandell, M.S.P.T. for her assistance in pilot work related to the methods for the tests described. This work was funded by the National Institute of Child Health and Human Development, National Center for Medical Rehabilitation Research, Grant #1 K01HD01226-05 and Grant#5 T32 HD07434-10.
Appendix A. Directions of movement or alignment potentially needed to be modified during secondary tests to decrease symptoms Primary tests are tests in which the patient assumes a trunk position or performs a trunk or limb movement using his preferred strategy. Symptoms with each primary test are monitored and compared to a reference position or movement. Any symptom-provoking primary test is immediately followed by a secondary test. Secondary tests are directed at decreasing the patient’s symptoms compared to symptoms during the associated primary test. The primary goal of the secondary tests for alignment is to attempt to position the lumbar region in as close to a neutral alignment (Adams and Dolan, 1995; McGill, 2002) as possible. The primary goal of the secondary tests for movement is to restrict or eliminate movement of the lumbar region while encouraging movement in other regions such as the thoracic region, shoulder joint or hip joint. Tests that involve movement of the limbs or movement of the trunk in the frontal or horizontal plane are performed both to the left and to the right. Specific directions of lumbar region movement or alignment may need to be modified to successfully decrease symptoms with individual secondary tests. The directions of movement or alignment that would potentially need to be modified for each test are provided below, see Table A1.
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L.R. Van Dillen et al. / Manual Therapy 14 (2009) 52e60 Table A1 Secondary test
Directions of movement or alignment potentially needed to be modified during secondary tests to decrease symptoms Flexiona
Tests of trunk alignment Sitting: flexion Sitting: extension Supine Side lying Prone Quadruped Tests of trunk movement Standing: forward bend Standing: return from forward bend Standing: lateral bend Quadruped: rock back
Rotationa,b
X
Flexion and rotationc
X
Extension and rotationc
X X X X X
X X
X
X
X
X
X
X
X X
X
Tests of limb movement Supine: knee extension X Supine: hip and knee flexion X Supine: hip abduction and lateral rotation Tests of limb movement Prone: knee flexion Prone: hip lateral rotation Prone: hip medial rotation Prone: hip extension Quadruped: shoulder flexion
Extensiona
X
X
X
X X
X X
X X X
X
X X X X X
X X
X
X
X
a
Indicates only one direction of movement or alignment would need to be modified to decrease symptoms. Because rotation and lateral bending are coupled motions in the lumbar region (Pearcy and Tibrewal, 1984; White and Panjabi, 1990) we currently categorize either of these as rotation. c Indicates both directions of movement or alignment would need to be modified to decrease symptoms. b
Appendix B. Operational definitions for symptom responses for primary and secondary tests 1. Increased: Symptoms were evoked or increased in intensity, or extended more distally. 2. Same: Symptoms were unchanged in intensity or location. 3. Decreased: Symptoms were diminished in intensity, or were located more proximally. 4. Eliminated: Symptoms were eliminated. In instances in which the findings for proximal and distal symptoms are different, the examiner prioritizes the behavior of the most distal symptoms to decide on the response (Van Dillen et al., 2001b).
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Bolton JE. Accuracy of recall of usual pain intensity in back pain patients. Pain 1999;83:533e9. Cailliet R. Clinical application of low back mechanics in the diagnosis and treatment of pain syndromes. In: Low back pain syndrome. 2nd ed. Philadelphia, PA: F.A. Davis; 1988. p. 49e57. Cicchetti DV, Sparrow SA. Developing criteria for establishing interrater reliability of specific items: applications to assessment of adaptive behavior. American Journal of Mental Deficiency 1981;86:127e37. Cyriax J. The lumbar region: examination. In: Textbook of orthopaedic medicine. 8th ed. London: Bailliere Tindall; 1982. p. 253e79. Delitto A, Erhard RE, Bowling RW. A treatment-based classification approach to low back syndrome: identifying and staging patients for conservative treatment. Physical Therapy 1995;75:470e85. Donelson R, Silva G, Murphy K. Centralization phenomenon. its usefulness in evaluating and treating referred pain. Spine 1990;15:211e3. Donelson R, Grant W, Kamps C, Medcalf R. Pain response to sagittal end-range spinal motion. A prospective, randomized, multicentered trial. Spine 1991;16:S206e12. Edwards BC. Clinical assessment: the use of combined movements in assessment and treatment. In: Twomey LT, Taylor JR, editors. Physical therapy of the low back. 2nd ed. New York: Churchill Livingstone Inc.; 1994. p. 197e220. Fairbank JC, Couper J, Davies JB, O’Brien JP. The Oswestry low back pain disability questionnaire. Physiotherapy 1980;66:271e3. Feinstein AR, Cicchetti DV. High agreement but low kappa: I. The problems of two paradoxes. Journal of Clinical Epidemiology 1990;43:543e9.
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Fritz JM, George S. The use of a classification approach to identify subgroups of patients with acute low back pain. Interrater reliability and short-term treatment outcomes. Spine 2000;25:106e14. Fritz JM, Delitto A, Erhard RE. Comparison of classification-based physical therapy with therapy based on clinical practice guidelines for patients with acute low back pain: a randomized clinical trial. Spine 2003;28:1363e71. Gombatto SP, Collins DR, Sahrmann SA, Engsberg JR, Van Dillen LR. Gender differences in pattern of hip and lumbopelvic rotation in people with low back pain. Clinical Biomechanics 2006;21:263e71. Gombatto SP, Collins DR, Engsberg JR, Sahrmann SA, Van Dillen LR. Patterns of lumbar region movement during trunk lateral bending in two different subgroups of people with low back pain. Physical Therapy 2007;87:441e54. Harris Hayes M, Sahrmann SA, Van Dillen LR. Classification and treatment outcomes of a patient with lumbar extension syndrome. Physiotherapy Theory and Practice 2005;21:1e16. Long AL. The centralization phenomenon: its usefulness as a predictor of outcome in conservative treatment of chronic low back pain (a pilot study). Spine 1995;20:2513e21. Long AL, Donelson R, Fung T. Does it matter which exercise? A randomized control trial of exercise for low back pain. Spine 2004;29:2593e602. Maitland GD. Selection of techniques. In: Vertebral manipulation. 5th ed. London: Butterworth & Co Ltd; 1986. p. 115e43. Maitland GD, Edwards BC. Examination. In: Vertebral manipulation. 5th ed. London: Butterworth & Co. Ltd; 1986. p. 43e92. Maluf KS, Sahrmann SA, Van Dillen LR. Use of a classification system to guide nonsurgical management of a patient with chronic low back pain. Physical Therapy 2000;80:1097e111. McGill S. Low back disorders: evidence-based prevention and rehabilitation. 1st ed. Champaign, IL: Human Kinetics Publishers; 2002. McKenzie R, May S. Physical examination. In: The lumbar spine mechanical diagnosis & therapy. 2nd ed, vol. 2. Waikanae, New Zealand: Spinal Publications New Zealand Ltd; 2003. p. 395e422. McKenzie R, May S. The lumbar spine: mechanical diagnosis & therapy. 2nd ed, vol. 1. Waikanae, New Zealand: Spinal Publications New Zealand Ltd; 2003. Moffroid MT, Haugh LD, Henry SM, Short B. Distinguishable groups of musculoskeletal low back pain patients and asymptomatic control subjects based on physical measures of the NIOSH Low Back Atlas. Spine 1994;19:1350e8. Mueller MJ, Maluf KS. Tissue adaptation to physical stress: a proposed ‘‘physical stress theory’’ to guide physical therapist practice, education, and research. Physical Therapy 2002;82:383e403. Norton BJ, Sahrmann SA, Van Dillen LR. Differences in measurements of lumbar curvature related to gender and low back pain category. Journal of Orthopedic and Sports Physical Therapy 2004;34:524e33. Pearcy MJ, Tibrewal SB. Axial rotation and lateral bending in the normal lumbar spine measured by three-dimensional radiography. Spine 1984;9:582e7.
Sahrmann SA. Movement impairment syndromes of the lumbar spine. In: Diagnosis and treatment of movement impairment syndromes. 1st ed. St. Louis, MO: Mosby Inc.; 2002. p. 5e118. Scholtes SA, Van Dillen LR. Gender-related differences in prevalence of lumbopelvic region movement impairments in people with low back pain. Journal of Orthopaedic and Sports Physical Therapy, in press. Spitzer WO, LeBlanc FE, Dupuis M. Scientific approach to the assessment and management of activity related spinal disorders: a monograph for clinicians. Report of the Quebec task force on spinal disorders. Spine 1987;12:S1e59. Spratt KF, Lehmann TR, Weinstein JN, Sayre HA. A new approach to the low-back physical examination. Behavioral assessment of mechanical signs. Spine 1990;15:96e102. Turner J, Sarvaiya-Shah S, Trudelle-Jackson E. Interrater reliability of the movement impairment classification for lumbar spine syndromes in patients with chronic low back pain. Journal of Orthopaedic and Sports Physical Therapy 2005;35:A267. Van Dillen LR, Sahrmann SA. Outcomes of classification-directed intervention in people with chronic or recurrent low back pain. Journal of Orthopaedic and Sports Physical Therapy 2006;36:A61e2. Van Dillen LR, Sahrmann SA, Norton BJ, Caldwell CA, Fleming DA, McDonnell MK, et al. Reliability of physical examination items used for classification of patients with low back pain. Physical Therapy 1998;78:979e88. Van Dillen LR, Sahrmann SA, Norton BJ, Caldwell CA, Fleming DA, McDonnell MK, et al. Effect of active limb movements on symptoms in patients with low back pain. Journal of Orthopaedic and Sports Physical Therapy 2001;31:402e13. Van Dillen LR, Sahrmann SA, Norton BJ, McDonnell MK, Fleming DA, Caldwell CA, et al. Response to invited commentary. Journal of Orthopaedic and Sports Physical Therapy 2001;31: 416e8. Van Dillen LR, Sahrmann SA, Norton BJ, Caldwell CA, McDonnell MK, Bloom NJ. The effect of modifying patientpreferred spinal movement and alignment during symptom testing in patients with low back pain: a preliminary report. Archives of Physical Medicine and Rehabilitation 2003;84:313e22. Van Dillen LR, Sahrmann SA, Norton BJ, Caldwell CA, McDonnell MK, Bloom NJ. Movement system impairment-based categories for low back pain: Stage 1 validation. Journal of Orthopaedic and Sports Physical Therapy 2003;33:126e42. Van Dillen LR, Sahrmann SA, Wagner JM. Classification, intervention, and outcomes for a person with lumbar rotation with flexion syndrome. Physical Therapy 2005;85:336e51. Waddell G. The back pain revolution. Edinburgh: Churchill Livingstone; 1998. Waddell G, Newton M, Henderson I, Somerville D, Main CJ. A Fearavoidance beliefs questionnaire (FABQ) and the role of fearavoidance beliefs in chronic low back pain and disability. Pain 1993;52:157e68. White AA, Panjabi MM. Clinical biomechanics of the spine. Philadelphia, PA: Lippincott; 1990.
Available online at www.sciencedirect.com
Manual Therapy 14 (2009) 61e67 www.elsevier.com/math
Original article
Relationship between spinal stiffness and outcome in patients with chronic low back pain Manuela Loureiro Ferreira a,b,*, Paulo Henrique Ferreira a,c, Jane Latimer a, Robert Dale Herbert a, Christopher Maher a, Kathryn Refshauge a b
a School of Physiotherapy, University of Sydney, Sydney, Australia Departamento de Fisioterapia, Pontifı´cie Universidade Cato´lica de Minas Gerais, Av. Dom Gaspar, 500 Coracao Eucaristico, Belo Horizonte, Brazil c Departamento de Fisioterapia, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
Received 11 December 2006; received in revised form 22 August 2007; accepted 19 September 2007
Abstract Many manual therapists assess and treat spinal stiffness of people with low back pain. The objectives of this study were to investigate: (i) whether spinal stiffness changes after treatment; (ii) the relationship between pre-treatment spinal stiffness and change in stiffness with treatment; (iii) the relationship between spinal stiffness, pain, disability and global perceived effect of treatment; (iv) whether spinal stiffness predicts outcome of treatment or response to treatment in chronic low back pain patients. One hundred and ninety-one subjects with chronic low back pain were randomly allocated to groups that received either spinal manipulative therapy, motor control exercise, or a general exercise program. Spinal stiffness was assessed before and after intervention. All three groups showed a significant decrease in stiffness following treatment ( p<0.001). No difference between groups was observed. There was a significant negative correlation between pre-treatment stiffness and change in stiffness (r¼0.61; p<0.001). There was a significant but weak correlation (r¼0.18; p¼0.02) between change in stiffness and change in global perceived effect of treatment, and a significant but weak correlation between change in stiffness and change in function for subjects in the spinal manipulative therapy group (r¼0.28; p¼0.02). No significant association was observed between initial stiffness score and any of the final outcome measures following treatment. Initial stiffness did not predict response to any treatment. In conclusion, spinal stiffness decreases over the course of an episode of treatment, more so in those with the stiffest spines, but the decrease is not dependent on treatment and is not generally related to outcome. Ó 2007 Elsevier Ltd. All rights reserved. Keywords: Spinal stiffness; Low back pain; Spinal manipulative therapy; Exercise
1. Introduction Spinal manipulative therapy is defined as the practice of manually applying forces to the spine to assess and treat patients with spinal pain (Maitland et al., 2001). * Corresponding author. Departamento de Fisioterapia, Pontifı´ cie Universidade Cato´lica de Minas Gerais, Av. Dom Gaspar, 500 Coracao Eucaristico, Belo Horizonte, Brazil. Tel.: þ55 31 3319 4114. E-mail address:
[email protected] (M.L. Ferreira). 1356-689X/$ - see front matter Ó 2007 Elsevier Ltd. All rights reserved. doi:10.1016/j.math.2007.09.013
Prior to using spinal manipulative therapy, a thorough assessment is performed of patients’ symptoms and their responses to active and passive movement tests (Maitland et al., 2001). This usually involves manual assessment of spinal motion. One test of spinal motion is the central posteroanterior (PA) pressure, which assesses PA spinal stiffness and pain reproduced with PA pressure. The test involves manual application of an oscillatory PA force or pressure over the patient’s spinous processes. The reliability
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M.L. Ferreira et al. / Manual Therapy 14 (2009) 61e67
of manual judgments of PA stiffness is poor when traditional testing protocols are used (Maher and Adams, 1994). In contrast excellent reliability and validity is possible if the stiffness testing protocol is closely controlled and a reference stiffness stimuli is provided to clinicians (Maher et al., 1998; Chiradejnant et al., 2003). Manual stiffness judgments made using this reference-based protocol demonstrate high inter-rater reliability (ICC¼0.78) and criterion-related validity (correlation between machine ratings and manual judgements¼0.74) and hence are suitable for assessing whether spinal stiffness has changed following intervention. PA spinal stiffness has been shown to depend on the frequency of mechanical excitation (Keller and Colloca, 2007) and the level of muscle stimulation in the ovine spine (Keller et al., 2007). Moreover, it has been hypothesised that there is a relationship between spinal pain, reduced voluntary movement and abnormal spinal stiffness, and that restoration of normal spinal stiffness will result in a reduction of symptoms and a return of voluntary movement (Latimer et al., 1996; Shirley, 2002). However, because of the poor reliability of traditional protocols used to assess PA stiffness, there has been little investigation of the relationship between manual PA stiffness and pain or movement (Lee et al., 1998; Maher et al., 1998). One study conducted by Latimer et al. in 1996 obtained instrumented measures of PA stiffness in 25 subjects with low back pain when pain was first present and when it had decreased by more than 80% (Latimer et al., 1996). The authors concluded that PA stiffness declined as pain abated, while pain-free subjects showed no change in PA stiffness over time. No statistical association was reported between pain and stiffness. Instrumented measures of PA stiffness also decreased significantly as pain resolved in 15 patients with acute low back pain (Shirley, 2002). The authors showed that people with higher pain had higher PA stiffness, but significant linear correlations between pain and stiffness were not found. Similarly, Brown et al. (2002) showed that intra-operative spinal stiffness measurements did not correlate with patients’ levels of satisfaction with lumbar surgery. However, the effect of low back pain treatment on PA stiffness has not been evaluated, and the relationship between PA stiffness and patients’ outcomes such as pain, disability and health status is not clear. The aims of the current study were to investigate, in patients with chronic low back pain: (i) whether spinal stiffness changes after treatment, or is changed by treatment; (ii) whether a relationship exists between pre-treatment spinal stiffness and change in stiffness with treatment; (iii) the relationship between change in stiffness, change in pain, change in disability and change in global perceived effect (GPE); (iv) whether baseline spinal stiffness predicts outcome or response to treatment.
2. Methods 2.1. Subjects Subjects with chronic low back pain who were participants in a randomised clinical trial evaluating the efficacy of physiotherapy treatment of low back pain were invited to participate in this study. Patients who approached the hospital outpatient physiotherapy departments of three large public hospitals in Sydney, Australia, seeking treatment for low back pain were invited to participate in the primary trial. The results of this trial have been published elsewhere (Ferreira et al., 2007). To be eligible for inclusion, patients had to have non-specific low back pain of at least 3 months duration and be aged between 18 and 80 years. They were screened for serious low back pathology and contraindications to exercise and spinal manipulative therapy by a physiotherapist, and they were excluded if they had neurological signs or specific spinal pathology (e.g., malignancy, inflammatory joint or bone disease) or if they had undergone back surgery. Prior to commencing the study, ethics approval was obtained from the University of Sydney Human Research Ethics Committee, as well as the South Western and Western Sydney Area Health Services. After signing a written consent form, subjects were randomised to groups using sealed opaque envelopes. Eighty subjects were randomly allocated to each of three treatment groups: general exercise, spinal manipulative therapy and motor control exercise. Of these 240 subjects, only 191 joined this spinal stiffness study (60 subjects included in the Motor Control Exercise group, 60 from the General Exercise group and 71 from the Spinal Manipulative Therapy group). The remaining 49 subjects did not participate because they were unable to lie prone for the assessment, their symptoms were too severe for the test to be performed, or they did not agree to spinal stiffness testing. 2.2. Outcome measures Before commencing treatment, all subjects underwent a physical assessment performed by the treating physiotherapist. A blinded assessor measured the following variables and manually assessed spinal stiffness of all participating subjects, before and after 8 weeks of treatment: 1. Global perceived effect: GPE was measured on an 11-point scale that ranged from 5 (vastly worse) to 5 (completely recovered), with 0 being no change (Ross and LaStayo 1997). 2. Patient-specific functional status (PSFS): Subjects were required to list three activities they had trouble with as a result of their low back pain and rate the
M.L. Ferreira et al. / Manual Therapy 14 (2009) 61e67
degree of difficulty of each activity from 1 (unable to perform) to 10 (able to perform at pre-injury level). The scores for the three activities were summed giving a total score that could range from 3 to 30 (Westaway et al., 1998). 3. Roland Morris Disability Questionnaire (RMDQ): This questionnaire consists of 24 statements related to activities of daily living commonly affected by low back pain. Subjects were asked to tick the statements that truly represented their status that day. Each ticked statement was worth 1 point, giving a score out of 24 (Roland and Morris, 1983). 4. Average pain intensity over last 24 h was measured on a visual analogue scale, where 0 represented no pain and 10 represented the worst pain possible (Ross and LaStayo, 1997). 5. Spinal stiffness was manually assessed by two raters who were qualified physiotherapists. Both raters had used PA mobilisation techniques for at least 8 years. Assessments before and after treatment intervention were performed by the same rater to remove interrater variability. The assessors were blinded to allocation. When assessing stiffness post-intervention they were also blinded to baseline stiffness and outcome measurements. 2.2.1. Procedure Prior to the study, the raters were asked to practise applying forces between 30 and 120 N (3e13 kg) on a set of bathroom scales to improve the accuracy of their force delivery (Keating et al., 1990). For manual stiffness testing, the reference-based protocol described by Chiradejnant et al. (2003) was used. Subjects were asked to lie prone on a plinth with head down, arms to the side and their lower backs exposed. The most symptomatic lumbar spine level was identified, marked and recorded for the post-treatment assessment. The rater then tested stiffness using a pisiform grip. A PA force was applied three times over the most symptomatic spinal level at a frequency of 1 Hz as the subject held his or her breath at the end of normal expiration. This was based on the findings of Macfadyen et al. (1998) showing that peak discriminability was provided when manual stiffness was assessed using three oscillations. Raters were encouraged to ignore the first cycle, when judging spinal stiffness, since there is a significant increase in stiffness and displacement between the first and subsequent oscillatory cycles (Shirley et al., 2002). The frequency was determined with the aid of a metronome. Because visual state (eyes closed vs. eyes open) can interfere with spinal stiffness judgement, visual state was standardised during testing, by asking raters to look at their own hands (Maher and Adams, 1994). Raters were also told to concentrate on the loading portion of the forceedisplacement curve when trying to match the stiffness.
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A stiffness reference device was used to anchor judgements of stiffness based on an 11-point scale (Chiradejnant et al., 2003). The device consists of a metal lever and a contact pad, which rest on a compression spring at its free end. By adjusting the position of the spring as well as the spring itself, the stiffness of downward movements of the metal lever could be increased or decreased and used as a reference for stiffness judgements made when a manual PA pressure was applied over the subject’s spine. The stiffness reference device was placed immediately adjacent to the plinth, at the subject’s feet, so that the same conditions were applied to both situations. The task for the rater was to change the location and size of the springs in the reference device to match the stiffness of the reference device to perceived stiffness of the lumbar spine. The rater then noted which spring best matched the subject’s spinal stiffness and marked this on an 11-point scale. The criterion validity of this protocol was tested in a subset of 28 chronic low back pain subjects participating in the present study. The stiffness assessment machine (SAM), a mechanical device designed specifically for measurement of responses to PA vertebral mobilisation, was used as the reference standard (Latimer et al., 1996). A correlation of 0.50 ( p¼0.007) was found between the manual stiffness assessment protocol and the reference standard.
2.3. Interventions Subjects in the three groups received an eight-week treatment program provided by a physiotherapist. (i) General Exercise group: An initial individual assessment was performed by the physiotherapist to determine the amount of physical activity of the subject, how troublesome the back problem was, and the ability of the subject to perform the exercises. Subjects were then taught the individual non-specific stretching and strengthening exercises and informed of the level at which they should be performing the exercises. Classes were delivered in groups of eight. Subjects were encouraged to finish all 12 sessions even if they had completely recovered. (ii) Motor Control Exercise group: Subjects allocated to this group were prescribed exercises aimed at improving function of specific muscles of the low back region (Richardson et al., 1999). The aim was for subjects to relearn the ability to recruit the deep muscles of the spine and gradually reduce unwanted over-activity of the global muscles. Feedback with the aid of real-time ultrasound was encouraged in the first treatment session to facilitate the activation of the deep abdominal
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muscles. Daily home exercises were encouraged and monitored to enhance compliance. (iii) Spinal Manipulative Therapy group: An initial standard assessment was performed by the treating physiotherapist including a complete history and physical examination relevant to the problem. Joint mobilisation or manipulation techniques were then applied to the subject’s spine or pelvis. The choice of technique was at the discretion of the treating physiotherapist, according to the subject’s physical examination findings. Subjects in all groups were to attend 12 sessions in 8 weeks. Subjects allocated to the General Exercise group had 2 sessions per week for the first 4 weeks and 1 session per week for the last 4 weeks. Subjects allocated to the Spinal Manipulative Therapy group or Motor Control Exercise group also attended 12 sessions but the timing of the sessions was at the physiotherapist’s discretion. Subjects were asked not to seek other treatments and where possible not to change current medications for the 8-week trial period.
Table 1. All groups showed a significant decrease in mean stiffness following treatment ( p<0.001 for all three groups); on average the decrease was 1.2 points on the 11-point scale. No difference between group changes was observed when Spinal Manipulative Therapy group was compared to the Motor Control Exercise group (mean difference¼0.49; 95% CI: 1.00 to 0.04; p¼0.07), when Spinal Manipulative Therapy group was compared to General Exercise group (0.09; 95% CI: 0.49 to 0.65; p¼0.77) or when the Motor Control Exercise group was compared to the General Exercise group (0.40; 95% CI: 0.92 to 0.12; p¼0.13). 3.2. Pre-treatment stiffness vs. change in stiffness A strong negative correlation was found between pretreatment stiffness and change in stiffness (r¼0.61; p<0.001) for all subjects. When the three groups were analysed separately, significant correlations of 0.40 ( p¼0.02) for the Motor Control Exercise group, 0.77 ( p<0.001) for Spinal Manipulative Therapy group and 0.62 ( p<0.001) for the General Exercise group were found.
2.4. Analysis Paired samples t-tests were used to test changes in stiffness within each treatment group. The 95% confidence intervals for mean differences between the three treatment groups’ mean changes were estimated using the t-distribution. Pearson’s correlation was used to analyse the relationship between pre-treatment stiffness scores and change in stiffness, change in pain, change in RMDQ, change in PSFS and change in GPE scores. The analyses were conducted within each group and for the pooled data of all three groups. Multiple linear regression was used to determine if baseline stiffness predicted either outcomes or responses to treatment. GPE, PSFS, RMDQ and pain scores were the outcome variables in separate regression models. Pre-treatment stiffness scores, group, baseline scores and the interactions between stiffness score and group were explanatory variables. The three groups were dummy coded. The pre-treatment stiffness term was used to assess if pre-treatment stiffness predicted outcome, and the interaction between stiffness and group was used to assess if pre-treatment stiffness predicted response to treatment.
3.3. Relationship between stiffness and change in outcome No significant correlation was found between change in stiffness and change in pain, disability or function (Table 2). A weak negative correlation of 0.18 ( p¼0.02) was observed between change in stiffness and change in GPE for all subjects. A weak negative correlation was also found between stiffness change and function change for subjects in the Spinal Manipulative Therapy group (0.28; p¼0.02). No other significant correlations were found. 3.4. Stiffness as predictor of outcome or of response to treatment No significant association was observed between initial stiffness and any of the final outcome measures Table 1 Mean (S.D.) pre-treatment, post-treatment and change in stiffness scores for each group Motor control exercise (n¼60)
Spinal manipulative therapy (n¼71)
General exercise (n¼60)
All subjects (n¼191)
1.3 (1.3) 0.4 (1.5) 0.9 (1.3) <0.001
1.1 (1.5) 0.3 (1.1) 1.4 (1.7) <0.001
1.1 (1.5) 0.2 (1.4) 1.3 (1.6) <0.001
1.1 (1.5) 0.0 (1.3) 1.2 (1.5) <0.001
3.1. Change in stiffness
Pre-treatment Post-treatment Change p
Mean pre-treatment stiffness, post-treatment stiffness and change in stiffness of each group are presented in
Stiffness is measured on an 11-point scale (5 to þ5). Data are means and S.D.s. n: sample size. The p-value is for the hypothesis that the change in stiffness¼0.
3. Results
M.L. Ferreira et al. / Manual Therapy 14 (2009) 61e67 Table 2 Correlations (r) between change in stiffness and change global perceived effect, function, disability and pain outcomes Outcome Motor control exercise (n¼60) GPE PSFS RMDQ Pain
0.16 0.09 0.02 0.06
Spinal manipulative therapy (n¼71)
General exercise (n¼60)
All subjects (n¼191)
(0.21) 0.14 (0.25) 0.18 (0.17) 0.18 (0.02)) (0.52) 0.28 (0.02)) 0.04 (0.74) 0.13 (0.08) (0.86) 0.00 (0.98) 0.17 (0.19) 0.06 (0.40) (0.64) 0.23 (0.53) 0.04 (0.77) 0.11 (0.15)
Data in brackets are p-values. GPE: global perceived effect (5 to þ5); PSFS: Patient-specific functional scale (1e30); RMDQ: Roland Morris Disability Questionnaire score (0e24). Pain: pain intensity measured on a visual analogue scale (0e10). ) p<0.05.
following treatment, showing that initial stiffness does not predict outcome in subjects with chronic low back pain (Table 3). The interaction term was not significant for any outcome suggesting that initial stiffness does not influence response to treatment. Table 3 Prediction of outcomes from initial spinal stiffness Outcome Predictor
Regression 95% CI coefficient
p
GPE
Constant 1.92 Initial stiffness 0.30 Initial GPE 0.13 SMT 1.01 MCE 1.29 SMTinitial stiffness 0.16 SSEinitial stiffness 0.22
1.11 0.67 0.02 0.06 0.31 0.35 0.31
to to to to to to to
2.74 0.07 0.28 1.97 2.27 0.67 0.75
PSFS
Constant 8.24 Initial stiffness 0.63 Initial PSFS 0.71 SMT 1.26 MCE 2.28 SMTinitial stiffness 0.96 SSEinitial stiffness 0.38
5.69 1.64 0.53 1.28 0.31 0.39 1.03
to to to to to to to
10.79 <0.001 0.38 0.22 0.90 <0.001 3.79 0.33 4.86 0.08 2.32 0.16 1.79 0.60
RMDQ
Constant 0.10 Initial stiffness 0.34 Initial RMDQ 0.63 SMT 0.94 MCE 0.54 SMTinitial stiffness 0.04 SSEinitial stiffness 0.18
1.98 0.45 0.50 2.92 2.73 1.13 1.00
to to to to to to to
2.19 1.14 0.75 1.04 1.64 1.05 1.37
0.92 0.39 <0.001 0.35 0.63 0.95 0.76
Pain
Constant 1.73 Initial stiffness 0.21 Initial pain 0.43 SMT 0.16 MCE 0.72 SMTinitial stiffness 0.40 SSEinitial stiffness 0.02
0.39 0.19 0.26 1.18 1.77 0.95 0.55
to to to to to to to
3.07 0.61 0.59 0.87 0.33 0.15 0.59
0.01 0.30 <0.001 0.76 0.18 0.15 0.94
<0.001 0.11 0.10 0.04 0.01 0.53 0.41
Regression coefficients are unstandardised (i.e., they represent the change in outcome for a unit change in predictor). GPE: global perceived effect (5 to þ5); PSFS: Patient-specific functional scale (1e 30); RMDQ: Roland Morris Disability Questionnaire score (0e24); Pain: pain intensity measured on a visual analogue scale (0e10); SMT: spinal manipulative therapy; MCE: motor control exercise.
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4. Discussion Manual stiffness tests are widely used in the assessment of patients with low back pain. The value of these tests is still unclear. Our results show that stiffness decreases over the course of an 8-week treatment period. The decrease in stiffness is similar in patients receiving spinal manipulative therapy or exercise as a treatment intervention. Change in stiffness is negatively correlated with initial stiffness, but there is little or no correlation between change in stiffness and change in clinically important outcomes, or between initial stiffness and clinically important outcomes. The protocol used in the present study included using an 11-point scale (5 to 5) to assess spinal stiffness, with values ranging from 4.14 to 25.57 N/mm. Data variability of scales is usually difficult to interpret. However, frequency analyses of the data show that initial stiffness values ranged from 7.26 to 23.82 N/mm, with 58.6% of these subjects showing values ranging from 15.25 to 17.30 N/mm. Post-treatment spinal stiffness values still ranged from 7.26 to 23.82 N/mm, but 77.5% of subjects who participated in the study, showed stiffness values ranging from 11.53 to 15.25 N/mm. It could be argued that the protocol employed to measure spinal stiffness in the present study was not accurate enough to provide true measurements of spinal stiffness. However, when a subset of the sample was used to verify the criterion validity of the protocol, a satisfactory correlation of 0.5 was found. Although further evidence is necessary to confirm that the protocol used provides a valid measure of lumbar stiffness, this protocol is likely to be more accurate than the clinical manual tests performed by clinicians in their daily routine and consequently we would expect our data to overestimate the predictive value of clinical assessments of stiffness. Our findings of a significant reduction in stiffness over the course of treatment are in accordance with the findings of Latimer et al. (1996). These authors found a significant mean decrease in instrumented measurements of stiffness of 8% in patients with acute and subacute low back pain over the period of resolution of their pain. This change was not observed in an asymptomatic control group. Shirley (2002) also observed a 9% ( p¼0.03) decrease in instrumented measures of spinal stiffness as pain resolved in an acute low back pain population. Again, the author did not observe a reduction in stiffness in the control group, suggesting that change in stiffness was associated with back pain (low back pain group vs. control group), rather than by the initial levels of spinal stiffness. In the present study, an average decrease in stiffness of 1.2 on an 11-point scale was observed using a manual stiffness assessment protocol. According to Chiradejnant et al. (2003), the standard error of the measurement (SEM) of the protocol used is 0.56. The mean increase in
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stiffness for all subjects in our study is at least twice that value, showing that this change could not be explained by error of the measurement, but rather represents a true change in stiffness. Our results show that there is a significant reduction in spinal stiffness over time in subjects with chronic low back pain. This change could not be explained by assessment bias, since raters did not have access to subjects’ initial spinal stiffness assessment scores, which was performed 8 weeks before post-treatment spinal stiffness assessment. However, there was no difference between stiffness changes across treatment groups suggesting that these changes are not specifically related to the application of spinal manipulative therapy. Similarly, Goodsell et al. (2000) demonstrated no change in spinal stiffness as a result of short-term PA mobilisations (one session) in patients with chronic low back pain. These data suggest that changes in stiffness occur as symptoms improve in patients with low back pain, and these changes are not directly due to the application of spinal manipulative therapy. Different factors could explain the change in spinal stiffness following treatment. Past research has shown that body mass index, pelvic rotation, the direction of applied force and patient position are related to variations in spinal stiffness (Edmonston et al., 1998; Lee et al., 1998; Caling and Lee, 2001; Chansirinukor et al., 2003). However, since subjects were measured in the same conditions and by the same assessor it is unlikely that variations in pelvic rotation, direction of application of force or positioning of patients could have caused the systematic drop in stiffness observed following treatment in the present study. It has been suggested that the human spinal stiffness is dynamically modulated by its intrinsic viscoelastic components, such as ligaments, muscles, tendons, as a response mechanism to different daily stimuli (Keller and Colloca, 2007). Therefore, changes in muscle activity (Shirley, 2002), as well as muscle stimulation (Keller et al., 2007) have been associated with changes in spinal stiffness. Spinal stiffness correlates with the level of transversus abdominis and diaphragm muscle contraction in pigs (Hodges et al., 2003), multifidus contraction in the ovine spine (Keller et al., 2007) and voluntary contraction of the lumbar extensor muscles increases PA spinal stiffness in humans (Shirley et al., 1999). It is possible, therefore, that reductions in involuntary muscle activity associated with resolution of pain may be responsible for the reductions in spinal stiffness observed over the course of treatment in this study. There was a negative correlation between pre-treatment stiffness and change in stiffness. In other words, subjects with greater baseline stiffness values tended to have a greater decrease in stiffness. We sought to determine if this relationship was simply due to regression to the mean (Newell and Simpson, 1990). Further analyses
using Blomqvist’s method (Blomqvist, 1977; Hayes, 1988) showed that after correcting for regression to the mean, the correlation between baseline stiffness scores and change in stiffness was 0.56 for all subjects and 0.82 for the Spinal Manipulative Therapy group. These values are very close to the observed correlations of 0.61 for all subjects and 0.77 for Spinal Manipulative Therapy group. That is, the relationship between baseline stiffness and change in stiffness is not due solely to regression to the mean. What clinical implications do the observed reductions in spinal stiffness have? It has been conceptualised that spinal stability is provided by the interaction of three systems: (i) passive inert tissues of the spinal column; (ii) muscles around the spine; (iii) neural control unit. Under normal condition, the three systems would work in harmony to provide mechanical stability of the spine (Panjabi, 2003). Based on this concept, Panjabi (2003) suggests that a decrease in the intervertebral motion would result in reduced pain. However, this has not been supported by our results. On average, subjects in this study experienced improvements in GPE, disability and pain scores. However, this improvement does not seem to be associated with change in stiffness and change in outcome. Shirley et al. (2002) reported similar findings in acute and subacute low back pain patients. Thus, even though stiffness declines with the resolution of low back pain, the clinical meaning of this decrease is still unclear. Investigations of whether physical examination tests have a prognostic role in the treatment of low back pain are scarce (Borge et al., 2001). A recent study showed that a clinical decision rule which incorporated manual assessment of spinal stiffness was able to identify those people with low back pain who respond best to spinal manipulation. (Those subjects with at least one hypomobile segment responded better to manipulation) (Childs et al., 2004). Our data, however, show no relationship between pre-treatment stiffness values and improvement in outcome following treatment, suggesting that measures of spinal stiffness might not contribute substantially to the discriminative accuracy of the clinical decision rule.
5. Conclusion These results demonstrate that, even though manually perceived spinal stiffness decreases after treatment in people with chronic low back pain, it does not predict meaningful clinical outcomes such as pain and disability and it does not predict response to treatment.
Acknowledgements This study was partially funded by research grants from the University of Sydney and Motor Accidents
M.L. Ferreira et al. / Manual Therapy 14 (2009) 61e67
Authority of New South Wales. Drs. Manuela and Paulo Ferreira received CAPES scholarships from the Brazilian Government. A/Prof. Christopher Maher and A/Prof. Robert Herbert research fellowships are funded by the National Health and Medical Research Council of Australia.
References Blomqvist N. On the relation between change and initial value. Journal of the American Statistical Association 1977;72:746e9. Borge JA, Lebouef-Yde C, et al. Prognostic values of physical examination findings in patients with chronic low back pain treated conservatively: a systematic literature review. Journal of Manipulative and Physiological Therapeutics 2001;24:292e5. Brown MD, Wehman KF, et al. The clinical usefulness of intraoperative spinal stiffness measurements. Spine 2002;27(9):959e61. Caling B, Lee M. Effect of direction of applied mobilization force on the posteroanterior response in the lumbar spine. Journal of Manipulative and Physiological Therapeutics 2001;24:71e8. Chansirinukor W, Lee M, et al. Contribution of ribcage movement to thoracolumbar posteroanterior stiffness. Journal of Manipulative and Physiological Therapeutics 2003;26:176e83. Childs JD, Fritz JM, et al. A clinical prediction rule to identify patients with low back pain most likely to benefit from spinal manipulation: a validation study. Annals of Internal Medicine 2004;141(12): 920e8. Chiradejnant A, Maher CG, et al. Objective manual assessment of lumbar posteroanterior stiffness is now possible. Journal of Manipulative and Physiological Therapeutics 2003;26:34e9. Edmonston SJ, Allison GT, et al. Effect of position on the posteroanterior stiffness of the lumbar spine. Manual Therapy 1998;3(1): 21e6. Ferreira ML, Ferreira PH, et al. Comparison of general exercise, motor control exercise and spinal manipulative therapy for chronic low back pain: a randomised trial. Pain 2007;131(1/2):31e7. Goodsell M, Lee M, et al. Short-term effects of lumbar posteroanterior mobilization in individuals with low-back pain. Journal of Manipulative and Physiological Therapeutics 2000;23(5):332e42. Hayes RJ. Methods for assessing whether change depends on initial value. Statistics in Medicine 1988;7:915e27. Hodges PW, Kaigle Holm A, et al. Intervertebral stiffness of the spine is increased by evoked contraction of transversus abdominis and the diaphragm: in vivo porcine studies. Spine 2003;28(23): 2594e601.
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Keating JC, Bergmann T, et al. Interexaminer reliability of eight evaluative dimensions of lumbar segmental abnormality. Journal of Manipulative and Physiological Therapeutics 1990;13:463e70. Keller TS, Colloca CJ. Dynamic dorsoventral stiffness assessment of the ovine lumbar spine. Journal of Biomechanics 2007;40:191e7. Keller TS, Colloca CJ, et al. Muscle contributions to dynamic dorsoventral lumbar spine stiffness. European Spine Journal 2007;16:245e54. Latimer J, Lee M, et al. An investigation of the relationship between low back pain and lumbar posteroanterior stiffness. Journal of Manipulative and Physiological Therapeutics 1996;19(9):587e91. Lee M, Steven GP, et al. Variations in posteroanterior stiffness in the thoracolumbar spine: preliminary observations and proposed mechanisms. Physical Therapy 1998;78(12):1277e87. Macfadyen N, Maher CG, et al. Number of sampling movements and manual stiffness judgements. Journal of Manipulative and Physiological Therapeutics 1998;21:604e10. Maher CG, Adams R. Reliability of pain and stiffness assessments in clinical manual lumbar spine examination. Physical Therapy 1994;74(9):801e11. Maher CG, Latimer J, et al. An investigation of the reliability and validity of posteroanterior spinal stiffness judgments made using a reference-based protocol. Physical Therapy 1998;78(8):829e37. Maitland GD, Banks K, et al. Lumbar spine. In: Maitland GD, Banks K, English K, Hengeveld E, editors. Maitland’s vertebral manipulation. Oxford: Butterworth-Heinemann; 2001. p. 325e83. Newell D, Simpson J. Regression to the mean. Medical Journal of Australia 1990;153:97e9. Panjabi MM. Clinical spinal stability and low back pain. Journal of Electromyography and Kinesiology 2003;13:371e9. Richardson CA, Jull GA, et al. Therapeutic exercise for spinal segmental stabilisation in low back pain: scientific basis and clinical approach. Edinburgh: Churchill Livingstone; 1999 [chapter 4, p. 125]. Roland M, Morris R. A study of the natural history of back paind Part I: development of a reliable and sensitive measure of disability in low-back pain. Spine 1983;8(2):141e3. Ross R, LaStayo P. Clinical assessment of pain. In: Van Deusen J, Brunt D, editors. Assessment in occupational therapy and physical therapy. Philadelphia: WB Saunders; 1997. p. 123e33. Shirley D. Muscle activity and lumbar PA stiffness. PhD thesis, School of Physiotherapy, University of Sydney, 2002. Shirley D, Ellis E, et al. The response of posteroanterior lumbar stiffness to repeated loading. Manual Therapy 2002;7(1):19e25. Shirley D, Lee M, et al. The relationship between submaximal activity of the lumbar extensor muscles and lumbar posteroanterior stiffness. Physical Therapy 1999;79(3):278e85. Westaway M, Stratford P, et al. The patient-specific functional scale: validation of its use in persons with neck dysfunction. Journal of Orthopaedic and Sports Physical Therapy 1998;27(5):331e8.
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Manual Therapy 14 (2009) 68e74 www.elsevier.com/math
Original article
Individual advice in addition to standard guideline care in patients with acute non-specific low back pain: A survey on feasibility among physiotherapists and patients Eric W.P. Bakker a,*, Arianne P. Verhagen a, Emiel van Trijffel b, Cees Lucas b, Hans J.C.M.F. Koning c, Bart W. Koes a b
a Department of General Practice, Erasmus University, Rotterdam, The Netherlands Department of Clinical Epidemiology, Biostatistics and Bioinformatics, Amsterdam Medical Centre, The Netherlands c Physiotherapy Centre, Prins Hendrikstraat 184, 2518 HZ The Hague, The Netherlands
Received 3 May 2007; received in revised form 9 September 2007; accepted 19 October 2007
Abstract The medical costs associated with low back pain (LBP) potentially pose an enormous economic burden to society. Prevention (secondary) might be beneficial when there is no definitive conclusion on the most appropriate intervention. For this purpose, individual advice focusing on modification of spinal mechanical load obtained with the 24 Hour Scheduled24HSd(an instrument for quantifying spinal mechanical load) in addition to standard care of guideline-recommendations might be effective. Naturally, this should be examined in controlled studies. Considering the costs involved carrying out a controlled study, the feasibility of 24HS-advice should be assessed first. We performed two surveys in primary care setting in 97 patients with acute (<6 weeks) non-specific LBP (who received a 24HS assessment and 24HS-advice at baseline), and 18 physiotherapists (all involved in 24HS baseline assessments). Patients and physiotherapists were first contacted by telephone after 6 months by a research assistant and requested to complete a questionnaire developed to assess feasibility. During this interview patients again completed a follow-up 24HS assessment. Eighty-eight patients and 17 physiotherapists participated in the follow-up. The median score of patients’ questionnaire was 7 (interquartile range 5.9e8.3) and of physiotherapists’ questionnaire 8 (interquartile range 7e8.5). Both questionnaires exceeded the criteria for feasibility, which we had previously set at seven or higher (out of 10). Subsequently, 24HS-advice was considered feasible for use in primary care healthcare providers and patients with LBP. In patients, the absence of LBP during the follow-up period and in physiotherapists ‘lack of time’ were identified as factors that could potentially threaten the feasibility in 24HS-advice. Ó 2007 Elsevier Ltd. All rights reserved. Keywords: Feasibility study; Low back pain; Prevention; 24 Hour Schedule
1. Introduction Low back pain (LBP) causes an economic burden to society in countries such as the USA, UK and The Netherlands (Maetzel and Li, 2002). Recently, a large number of
* Corresponding author. Tel.: þ31 10 408 8109; fax: þ31 10 408 9491. E-mail address:
[email protected] (E.W.P. Bakker). 1356-689X/$ - see front matter Ó 2007 Elsevier Ltd. All rights reserved. doi:10.1016/j.math.2007.10.002
systematic reviews were published concerning the effectiveness of treatments for LBP (van Tulder et al., 2000a, b; Guzma´n et al., 2001; Jellema et al., 2001; Ferreira et al., 2002; Pengel et al., 2002). Despite the large amount of evidence on LBP management, a definitive conclusion on the most appropriate intervention is not currently available. Prevention of recurrences and chronicity, however, was identified as an important goal in the management of LBP (Dugan, 2006).
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A previous study indicated that longer lasting and more intensive spinal loading in flexed positions, quantified with the 24 Hour Schedule (24HS: a questionnaire developed for quantifying subjects’ individual spinal mechanical load), was strongly associated with the occurrence of acute LBP (Bakker et al., 2003, 2007a). Modification of this spinal mechanical load may theoretically prevent recurrent episodes in patients with acute LBP (Bakker et al., 2007a, b). Such modification can be achieved through individualised advice, in addition to standard guideline care, using the results of the 24HS assessment (Bakker et al., 2007a). This way an individualised program for the self-management of LBP was developed. It is proposed that adding this 24HS-advice to the standard care in guideline recommendations may prove beneficial to patients. Whether this approach for LBP indeed is an effective intervention should be examined in controlled studies. The costs involved in a full scale randomised controlled trial can be considerable. Before starting a controlled study, the feasibility of an intervention should be examined. For example, non-compliance with therapeutic recommendations may be problematic in patients as well as in healthcare professionals (Bishop and Wing, 2003; Gold and McClung, 2006). In patients, variables related to the characteristics of the prescribed treatment could result in non-compliance with the treatment regimen (Turk and Rudy, 1991). In healthcare professionals, new therapeutic recommendations do not necessarily lead to practice changes unless these are accepted as valid and useful, and the benefits of the practice changes are expected to outweigh the difficulties linked to such changes (Geyman and Gordon, 1982). Therefore, the feasibility of 24HS-advice for use in clinical practice should be assessed first. The objective of this study was to assess the feasibility of 24HS-advice in additional to standard care in patients with LBP and in healthcare providers in primary care physiotherapy and manual therapy. 2. Methods A survey using a structured questionnaire was conducted among patients with LBP and their caregivers. 2.1. Study population Patients (n¼97) were participants of an inception cohort with acute (i.e. an episode of LBP lasting less than 6 weeks) non-specific LBP (Frymoyer, 1988; Bakker et al., 2007a, b). All patients were referred by general practitioners of the city of The Hague (The Netherlands) to an assessor in one of the four local research centres. Patients were eligible for inclusion if the assessor confirmed the ‘diagnosis’ acute LBP and the presence of exclusion criteria were expelled.
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Exclusion criteria were: insufficient understanding of the Dutch language, previous episode(s) of acute LBP in the past 12 months, low back pain after a recent trauma, pregnancy, spinal surgery, and known pathology suspicious for/or specific low back pain. Definitions used in this study are in accordance with the Dutch Guideline for General Practitioners ‘Low Back Pain’ and internationally accepted (Faas et al., 1996; Chavannes et al., 2005). After inclusion, all subjects signed informed consent, were coded to remain anonymous, and completed questionnaires focusing on subjects’ demographic and clinical data. The 24HS was used for the assessment of spinal mechanical loading (baseline measurement). 2.1.1. Therapists All assessors (n¼18) were physiotherapists trained in using the 24HS in two 90 min sessions and involved in previous studies with the 24HS. 2.2. The procedure of the 24HS measurement An assessor, trained in using the 24HS, systematically asked the patients to describe their daily activities. In each activity, the position of the back in the sagittal plane (i.e. flexed or extended), the load and duration applied were registered chronologically on the standardised registration form (see Addendum). For ‘load applied’ three categories were available: 1. No load applied (e.g. lying), 2. Loaded (e.g. sitting) and 3. Loaded with movement (e.g. digging). After completing the registration, subject’s flexed-posture score was calculated. Of each activity, the duration was multiplied by the weight of the category the activity was scored in and all obtained scores were added. The weight of the categories, based on Nachemsons’ findings modified by Sato (Nachemson, 1975; Sato et al., 1999), was set to 1:2:3, respectively (Bakker et al., 2003). For example, an activity scored 5 h in the second category on the registration form, becomes 10 h when recalculated to the first category. An activity scored 5 h in the third category will be recalculated to 15 h in the first category. The resulting figure represents the time the back was loaded in a flexed posture with a load of the first category. This parameter called Schedule Hours, ranges from 0 to 72. Subsequently, this procedure was repeated for the extended posture (range: 0e72). The sum score was obtained by subtracting the total time of the extended postures from the total time of the flexed postures. The resulting figure gives insight in the dominant use (the training activity) of the back (range: 72 Schedule Hours to þ72 Schedule Hours). Negative sum scores point to overall spinal use in extended positions and positive sum scores indicate overall spinal use in flexed postures.
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2.3. Treatment procedure After the assessment, all patients received standard care consisting of guideline-based information. First all patients were informed concerning the benign nature and unknown cause of the pain. Patients were encouraged to stay active and stimulated to resume all activities as normal. Finally, patients were reassured of a favourable prognosis and bed rest was discouraged (Chavannes et al., 1996; Koes et al., 2001; Faas et al., 2005). Next the outcome of the assessment of the 24HS was explained in non-technical language. This included a short explanation of the 24HS and how the sum score was obtained. Personalised advice was given to modify the 24HS sum score when indicated. Subjects were then encouraged to implement these recommendations in their daily activities and maintain those consequently even in absence of LBP. In case of persistent and/or exacerbated symptoms (including radiating leg pain), or experiencing adverse effects of the treatment, subjects were explicitly advised to consult their general practitioner (GP). Finally, all information was summarised in a brochure, which patients received. The mean total time required for the assessment was about 20 min; including 10 min for guideline based information, explanation, and summarising. 2.4. Follow-up 2.4.1. Patients After 6 months, a research assistant contacted subjects by telephone to evaluate the feasibility of the prescribed recommendations. Also again the 24HS was assessed and scores were compared with the baseline scores. This way, a quantitative indication of compliance was obtained. Regarding the course of subjects’ LBP, the duration of the complaints and recurrent episode(s) were also noted. Further, an eight-item questionnaire was used to assess factors, which could threaten the feasibility. A thorough search in electronic databases PubMed and Embase identified the following factors: the understanding of the diagnosis and causes of LBP and the prescribed regime, subjects’ expectations about the treatment, the belief that treatment was unnecessary or was no longer needed, ineffectiveness of treatment, and experience of adverse effects (Darnell et al., 1986; Silva et al., 1996; Park et al., 1999; Floyd et al., 2000; Lombas et al., 2001; Glanz and Rimer, 2005; Gold and McClung, 2006). The questionnaire contained two open format questions and six questions were phrased as statements. Responses were given on an 11-point Numeric Rating Scale (NRS) (Jeaschke et al., 1990) ranging from 0 to 10. All questions were formulated in order to link the recommendations and procedures of the treatment. The number of GP consultations for
persistent and/or exacerbated symptoms (including radiating leg pain), and/or experiencing adverse effects was registered. 2.4.2. Therapists A questionnaire survey was administered by 17 physiotherapists of whom 11 were trained manual therapists to evaluate how they valued using the 24HS during the study and whether they continued using it after the study period was finished. An 11-item questionnaire for healthcare professionals covered three domains relating to the use of the 24HS-advice in primary care: workload in daily practice (four items), usefulness of using individualised advice based on the 24HS (four items), and patients’ reactions (three items) (Geyman and Gordon, 1982). The questions were phrased as statements and responses were on an 11-point NRS that ranged from strongly disagree (0) to strongly agree (10). Furthermore, demographical data, experience, specialisation(s) and work setting were registered. Two open format questions were used to determine the most positive and most negative perceived characteristics of 24HS-advice concerning the implementation of this treatment in primary care practice. The questionnaire was completed during a telephone interview performed after completing the survey in patients by a research assistant. 2.5. Analyses All analyses were carried out in SPSS 14.0. Subjects’ baseline data, 24HS scores differences (baseline minus follow up), are presented with their mean and standard deviation (SD). In case of skewed distributions median and interquartile range (IQR) were used. Firstly, we decided by consensus that 24HS-advice is feasible in patients with LBP if the median score over all six questions of the questionnaire was seven or higher. All domains were equally weighted. Questionnaire scores are presented with their median and IQR. For each question we presented the number of patients that scored a 7 or higher (agreeestrongly agree) separately. Responses on the open format questions were collected and ranked in order of reported frequency. Next, the personal characteristics of the therapists were analysed and presented with their mean and SD or in case of skewed distributions the median and IQR were used. A priori, we decided by consensus that the 24HS would be feasible for use in a primary care setting when the median score of all 11 questions was seven or higher. All domains were equally weighted. The scores of the three domains of the questionnaire are presented with their median and IQR. For each question we presented the number of physiotherapists that scored a 7 or higher (agreeestrongly agree) separately. The
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responses on the open format questions were collected and ranked in order of reported frequency. Both respondents and research assistant were uninformed of the evaluation method used (in particular the threshold applied) to assess feasibility. The Medical Ethics Committee of the Erasmus Medical Centre (Rotterdam, The Netherlands) approved the study.
3. Results 3.1. Patients Of the 97 subjects of the original cohort, 88 had completed the follow-up and were interviewed again (Bakker et al., 2007a, b). The baseline characteristics of all subjects are shown in Table 1. Mean 24HS score at baseline of patients completing the follow-up was 34.6 (SD 8.1) and at follow-up was 1.1 (SD 14.1). The 24HS score Table 1 Baseline characteristics of the original cohort (n¼97) and completing the follow-up (n¼88)
Male (%) Mean age (SD) Previous episode(s) LBP (%) 24HS sum-scores, mean (SD) Median pain at inclusion (range) Duration of symptoms in days, mean (SD) Radiating leg pain (%)
Baseline (n¼97)
Follow up (n¼88)
52/97 40.7 70/97 34.4 6 11.7
49/88 41 58/88 34.6 5 11.8
(54) (13.5) (72) (8.2) (0e10) (6.7)
35/97 (36)
SD: standard deviation; LBP: low back pain.
(56) (14) (67) (8.1) (0e9) (6.7)
31/88 (35)
difference was 33.6 (SD 14.4). Chronicity of LBP (complaints lasting longer than 12 weeks) occurred in 12 (14%) subjects, of whom 8 (9%) had persistent complaints over the 6-month period. Recurrent episode(s)dall labelled as non-specific LBPdoccurred in 41 (47%), of whom 4 (5%) subjects had recurrent episode(s) lasting longer than 12 weeks. The median number of recurrent episode(s) was 1 (IQR 0e3). The results of the questionnaire, assessing the feasibility and the recommendations are shown in Table 2. For persistent and/or exacerbated symptoms (including radiating leg pain) and/or those experiencing adverse effects, seven (8%) subjects consulted their GP once and three subjects (3%) twice for baseline LBP. Similar, eight (20%) single consultations were registered for recurrent LBP. For the item understanding what could possibly cause LBP, two (2%) subjects had the lowest score (0) in contrast with 40 (45%) subjects with the highest score (10), meaning that almost half of all subjects understood completely how applied spinal mechanical load could cause LBP. For the understanding of the prescribed regimen, also an open format question was used. Here, subjects were asked to reproduce in their own wording the main issue of the treatment. In total, 76 subjects (86%) answered correctly by mentioning altering posture as an important part of the advices. Ten subjects (12%) described solitarily issues like lifting techniques or exercises. Two subjects (2%) stated to remember nothing. To determine whether the received treatment met subjects’ expectations, again an open format question was used. Subjects were asked for ‘missing items’. In this question, 83 subjects (94%) answered ‘nothing missing’. To indicate the likelihood that their LBP becomes a chronic condition, 15 subjects (17%) scored ‘absolute
Table 2 Domains, which could threaten the feasibility with the 24HS-advice in subjects with LBP (n¼88) Domains
Assessment
Understand possible cause Understand regime Subjects’ expectations Advice unnecessary or no longer needed Ineffectiveness
Question: ‘I understand what could cause my LBP’ (0¼strongly disagree to 10¼strongly agree)a Question: ‘I am able to prevent a recurrent episode LBP with the received advises’ (0¼strongly disagree to 10¼strongly agree). Question: Please give your grade for the received therapy (0¼totally discontented to 10¼totally contended) Question: ‘To which extend did you continue applying the advices consequently during the 6-months follow-up period as advised?’ (0¼never to 10¼always)b Question: ‘Will you resume complying with the advices in case of a recurrent episode?’ (0¼not at all to 10¼absolutely) Question: ‘Please estimate the likelihood that your LBP becomes a chronic condition’ (0¼absolute likely to 10¼absolute unlikely)
Score (IQR)
Scores of 7 or higher (%)
9 (7e10)
70 (79.5)
7 (5e9)
54 (61.4)
10 (8e10)
81 (92)
5 (5e7)
32 (36.4)
8 (6e10)
65 (73.9)
5 (4e7)
31 (35.2)
LBP: low back pain; 24HS: 24 h schedule; NRS: numeric rating scale. The median score with interquartile range (IQR) of the responses as given on the 11-point NRS. a Information concerning the ‘diagnosis’ non-specific low back pain was considered as standard guideline care and therefore not evaluated in this questionnaire. b As part of the treatment, subjects were instructed to continue applying the advices with or without complaints.
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unlikely’ and six (7%) had the maximum score (10), meaning they were convinced that their LBP would become chronic. Forty-nine subjects (55.7%) had a median score of seven or higher over all items of this questionnaire. The median score over all items of this questionnaire was 7 (IQR 5.9e8.3) reaching the threshold for feasibility that was set at 7 or higher. 3.2. Therapists From the 18 assessors, one stopped working as a physiotherapist, thus 17 completed the questionnaire. Seven (41%) were male and mean age was 40.6 (SD 9.1; range 22e52). Median number of years of working experience was 19 (IQR 8e25). All care providers were working in a primary care physiotherapy practice setting. The mean number of new patients with low back pain seen over a 1-month period was 10 (SD 5). The median number of 24HS assessments since the start of our study in subjects with acute non-specific LBP was 30 (IQR 14e70), taking about 10.6 min on average per assessment (SD 2.4). Median time required for 24HSbased advice was 10 min (IQR 9.5e15). The results of the questionnaire assessing the feasibility of the 24HS are shown in Table 3. To gain more insight in what the therapists experiences were when using the 24HS, two open format questions were used. They were asked for their most important motivation to continue or to stop using the 24HS after completing the study. The advantage of visualising and illustrating subjects’ spinal mechanical load was mentioned 12 times as a motivation for
continuing using the 24HS. Confronting and alerting patients were mentioned four times and individualising advice once. Reasons mentioned for stopping using the 24HS were lack of time (10 times), hardly seeing subjects with LBP (twice) and difficulties with the registration form (twice). Not considering to ‘stop using the 24HS’ was mentioned three times. The median score on all 11 questions was 8 (IQR 7e8.5) exceeding the threshold for feasibility a priori set at 7 or more. Three (18%) questionnaire scores were less then 7 (range: 6.6e6.9). The scores for the domains ‘workload’, ‘usefulness’ and ‘patients’ reactions’ were 8.3 (IQR 7e8.6), 8 (IQR 6.8e8.8), and 7.7 (IQR 7e8.3), respectively. All domains of the questionnaire exceeded the criteria for feasibility separately.
4. Discussion From the results of this study, surveying patients with acute non-specific LBP as well as their treating physiotherapists, it can be concluded that the 24HS-based advice is feasible in patients with LBP and in primary care physiotherapy. The overall score for feasibility for patients with LBP that received advice was 7 and the assessed score for feasibility in healthcare providers was 8. Therefore, a controlled study to assess the effectiveness of 24HS-based advice in patients with LBP can be considered. After 6 months, subjects indicated to be highly satisfied with the described approach with a median score of 10 (strongly agree). They also indicated with a score of 9 to understand how applied mechanical load (as a consequence of spinal use) could possibly
Table 3 Domains, which could threaten the feasibility of the 24HS-advice in healthcare professionals (n¼17) Domains
Question
Score (IQR)
Scores of 7 or higher (%)
Workload
The 24HS procedure is easy to learn A 24HS assessment is easy to carry out When informing and advising a patient with LBP thoroughly, using the 24HS spares me time Considering the workload and (dis-) advantages of the 24HS, new patients with LBP can be referred to me for a 24HS assessment
9 8 7 9
17 17 11 14
Usefulness
Using the 24HS I am able to illustrate clearly patients spinal use and applied mechanical load Using the 24HS I am able to explain clearly how patients could alter the applied spinal mechanical load I will continue using the 24HS in patients with LBP Individual preventive advice is lacking in all present LBP guidelines, but should be added to these
8 (7.5e9) 8 (8e9)
17 (100) 17 (100)
8 (5e8) 8 (7e10)
12 (70.6) 16 (94.1)
Patients reactions were positive on the received information and 24HS-advice Patients with LBP could be reassured of a favourable prognosis with the received information and 24HS-advice Considering patients questions and reactions during the 24HS, estimate how may of your patients understood the information and advises completely
8 (7e9) 8 (7e8.5)
17 (100) 15 (88.2)
8 (7e8)
15 (88.2)
Patients’ reactions
(8e9.5) (7.5e8) (6e8) (7.5e10)
(100) (100) (64.7) (82.4)
LBP: low back pain; 24HS: 24 h schedule; NRS: numeric rating scale. Questions presented (original in Dutch) as used in the questionnaire. The median scores with interquartile range (IQR) of the responses given on the 11-point NRS (0¼strongly disagree to 10¼strongly agree).
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cause LBP. Nevertheless, the subjects experienced difficulties in ‘applying the advices consequently’. At the same time, subjects also indicated (with a median score of 8) to resume complying with the advices in case of a recurrent episode. These scores suggest that the absence of LBP was most threatening the feasibility with the 24HS-advice in this cohort. In advance, especially the absence of LBP was considered a potential threat for the compliance with the advice given, because asymptomatic or chronic conditions were identified as important determinants for non-compliance in diverse treatment modalities and pain syndromes (Turk and Rudy, 1991; Miller, 1997). Expecting this problem, attempts were incorporated in the procedure of 24HS-advice in order to improve the compliance. For this, subjects must consider the suggested advises as feasible for implementation in their daily activities. If agreement was reached on this issue, subjects were instructed to maintain the advice even in absence of LBP. In addition, subjects were informed about possible consequences of non-compliance (Gold and McClung, 2006). Finally, all information was summarised in a brochure, which subjects received (Schaffer and Tian, 2003). Despite all effort, the score for ‘applying the advice consequently’ was only moderate. Unfortunately, this study provides insufficient information to understand the rationale of such moderate compliance. For further improvement of the compliance in 24HSbased advice, in depth interviews are necessary to further explore this phenomenon. In therapists the domain ‘usefulness’ was assessed as good (8). Also the responses in the open format question: the most important motivation for continuing using the 24HS after completing the study, were all associated with this domain. The score for the domain ‘workload’ had the highest score (8.3). Still improvement in logistics of 24HS assessments could be considered, since in the open format question ‘lack of time’ was mentioned frequently as potential reason to end using the 24HS. Because the therapists were highly experienced this critical comment was taken seriously. The 24HS assessments were achieved within a standardised treatment setting of 30 min (Bakker et al., 2007a). For example, a special fee for 24HS assessments could make extra time available and overcome this potential threat to feasibility. In advance (non-) compliance with 24HS-advice was considered to be an important independent variable in this specific treatment. This study identified subjects’ compliance and potential treats for compliance. In general, compliance with 24HS-advice can be considered to be satisfactory. Nevertheless, improvements regarding the compliance especially in pain free episodes can easily be made. In view of the available literature concerning noncompliance as threat in prescribed treatment regimes
73
(Sackett and Snow, 1979), non-compliance should be seen as an important independent variable affecting the effectiveness of treatments. Therefore, this variable should be objectified and considered as acceptable before introducing (new) treatments. In the literature no valid method to assess feasibility suitable for use in this study has been described as far as we know. It was unexpected that no valid method to assess feasibility was available in literature. For that reason the authors developed the method as used. Hereby the threshold based on median scores of the questionnaires (all domains were weighted equally, and 7 or higher means feasible) was set by consensus. We considered our method to have face- and expert validity. In this manner sufficient insight was achieved in the strong and weak points in 24HS-advice related feasibility as well as in patients as in healthcare professionals. Illiteracy is perhaps the most substantial barrier to successful patient education initiatives (Miller, 1997). The study population of consecutive primary care patients cannot be considered representative for the general population of LBP patients. All subjects actively sought medical care, which may be related to various socioeconomic factors. Therefore, poorly educated and foreign origin patients were possible underrepresented in this study. The feasibility with 24HS-advice in this group of patients may differ from the results of this study. Theoretically, the scores of the questionnaire for healthcare professionals could be overestimated (bias), since all participating physiotherapists were involved in previous studies with the 24HS. Still, the question assessing subjects’ opinion for the received treatment was evaluated by healthcare providers with 8 and by patients with 10. Since subjects had no such interest in the 24HS, the extend of this potential treat for internal validity could be limited. Nevertheless, the use of the 24HS should therefore be repeated in a different population. The data used for the 24HS was obtained from interviews using retrospective data for subjects’ description of ‘an average day’ the quality may therefore be questioned. For that reason, the 24HS scores are considered as an indication of the ‘true’ mechanical load only. 5. Conclusion We consider 24HS-advice feasible for use in primary care healthcare providers and patients with LBP. The absence of LBP during the follow-up period in subjects and ‘lack of time’ of care providers were identified as risk factors that could potentially threaten the feasibility in 24HS-advice. Conflict of interest None.
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Acknowledgements The authors highly appreciated the help of Mariska Maris, research assistant and Palmer Giddings for language editing.
Appendix A. Supplementary data Supplementary data associated with this article can be found in the online version at doi:10.1016/ j.math.2007.10.002.
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Gold DT, McClung B. Approaches to patient education: emphasizing the long-term value of compliance and persistence. The American Journal of Medicine 2006;119(4 Suppl 1):S32e7. Guzma´n J, Esmail R, Karjalainen K, Malmivaara A, Irvin E, Bombardier C. Multidisciplinary rehabilitation for chronic low back pain: systematic review. British Medical Journal 2001;322:1511e6. Jeaschke R, Singer J, Guyatt GH. A comparison of seven-point and visual analogue scales. Controlled Clinical Trials 1990;11:43e51. Jellema P, van Tulder MW, van Poppel MN, Nachemson AL, Bouter LM. Lumbar supports for prevention and treatment of low back pain. A systematic review within the framework of the Cochrane Back Review Group. Spine 2001;26(4):377e86. Koes BW, van Tulder MW, Ostelo R, Kim Burton A, Waddell G. Clinical guidelines for the management of low back pain in primary care: an international comparison. Spine 2001;26(22):2504e13. Lombas C, Hakim C, Zanchetta JR. Compliance with alendronate treatment in an osteoporosis clinic. Presented at the American Society for Bone and Mineral Research (ASBMR) 23rd Annual Meeting, Phoenix, AZ, 12e16 October 2001. Maetzel A, Li L. The economic burden of low back pain: a review of studies published between 1996 and 2001. Best practice & research. Clinical Rheumatology 2002;16(1):23e30. Miller NH. Compliance with treatment regimens in chronic asymptomatic diseases. The American Journal of Medicine 1997;17102(2A):43e9. Nachemson A. Towards a better understanding of low-back pain: a review of the mechanics of the lumbar disc. Rheumatology and Rehabilitation 1975;14(3):129e43. Park DC, Hertzog C, Leventhal H, Morrell RW, Leventhal E, Birchmore D, et al. Medication adherence in rheumatoid arthritis patients: older is wiser. Journal of the American Geriatrics Society 1999;47(2):172e83. Pengel HM, Maher CG, Refshauge KM. Systematic review of conservative interventions for subacute low back pain. Clinical Rehabilitation 2002;16:811e20. Sackett DL, Snow JC. The magnitude of compliance and noncompliance. In: Hayes RB, Taylor WB, Sackett DL, editors. Compliance in healthcare. Baltimore: Johns Hopkins University Press; 1979. p. 11e22. Sato K, Kikuchi S, Yonezawa T. In vivo intradiscal pressure measurement in healthy individuals and in patients with ongoing back problems. Spine 1999;24(23):2468e74. Schaffer SD, Tian L. Promoting adherence effects of theory-based asthma education. Clinical Nursing Research 2003;13:69e89. Silva RR, Munoz DM, Daniel W, Barickman J, Friedhoff AJ. Causes of haloperidol discontinuation in patients with Tourette’s disorder: management and alternatives. The Journal of Clinical Psychiatry 1996;57(3):129e35. Turk DC, Rudy TE. Neglected topics in the treatment of chronic pain patientsdrelapse, noncompliance, and adherence enhancement. Pain 1991;44(1):5e28. van Tulder M, Malmivaara A, Esmail R, Koes B. Exercise therapy for low back pain. A systematic review within the framework of the Cochrane Collaboration Back Review Group. Spine 2000;25(21):2784e96. van Tulder M, Ostelo R, Vlaeyen JWS, Linton SJ, Morley SJ, Assendelft WJJ. Behavioral treatment for chronic low back pain. A systematic review within the framework of the Cochrane Back Review Group. Spine 2000;25(20):2688e99.
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Manual Therapy 14 (2009) 75e80 www.elsevier.com/math
Original article
Immediate effects of bilateral manipulation of talocrural joints on standing stability in healthy subjects Francisco Alburquerque-Sendı´ n a,b,*, Ce´sar Ferna´ndez-de-las-Pen˜as a,c, Miguel Santos-del-Rey d, Francisco Javier Martı´ n-Vallejo e a Escuela de Osteopatı´a de Madrid, Spain Department of Physical Therapy, Universidad de Salamanca, Salamanca, Spain c Department of Physical Therapy, Occupational Therapy, Rehabilitation and Physical Medicine, Universidad Rey Juan Carlos, Alcorco´n, Madrid, Spain d Department of Human Anatomy and Histology, Universidad de Salamanca, Salamanca, Spain e Department of Statistic, Universidad de Salamanca, Salamanca, Spain b
Received 7 February 2007; received in revised form 16 October 2007; accepted 21 November 2007
Abstract The purpose of this study was to investigate the immediate effects of bilateral talocrural joint manipulation on standing stability in healthy subjects. Sixty-two healthy subjects, 16 males and 46 females, aged from 18 to 32 years old (mean: 21 3 years old) participated in the study. Subjects were randomly divided into two groups: an intervention group (n ¼ 32), who received manipulation of bilateral talocrural joints and a control group (n ¼ 30) which did not receive any intervention. Baropodometric and stabilometric evaluations were assessed pre- and 5 min post-intervention by an assessor blinded to the treatment allocation. Intra-group and intergroup comparisons were analysed using appropriate parametric tests. The results indicated that changes on the X coordinate range, length of motion, and mean speed approximated to statistical significance (P ¼ 0.06), and changes on the Y coordinate range reached statistical significance (P ¼ 0.02). Average X and Y motions, and anterioreposterior or lateral velocities did not show significant differences. Our results showed that bilateral thrust manipulation of the talocrural joint did not modify standing stability, that is, the behavioural pattern of the projection of the centre of pressure, in healthy subjects. Ó 2007 Elsevier Ltd. All rights reserved. Keywords: Standing balance; Stabilometric; Baropodometric
1. Introduction Postural control is achieved through accumulation of sensory information, postural reactions (feedback or feed-forward), personal experiences (memory), muscular and joint afferent input. Sensory information supplies a significant contribution to postural control. The
* Corresponding author. EU Enfermerı´ a y Fisioterapia, Universidad de Salamanca, c/ Donante de sangre s/n, Campus Miguel de Unamuno, 37007 Salamanca, Spain. Tel.: þ34 626 880 871; fax: þ34 923 294 576. E-mail address:
[email protected] (F. Alburquerque-Sendı´ n). 1356-689X/$ - see front matter Ó 2007 Elsevier Ltd. All rights reserved. doi:10.1016/j.math.2007.11.005
oculo-motor, vestibular, and the somato-sensory systems provide the necessary inputs for the maintenance of posture (Miralles and Heras, 2005). The foot and ankle can be considered a proprioceptive contributor to the postural system because it allows for segmental adjustments of the lower extremity while remaining a fixed point on the contacting surface (Villeneuve, 1990). Previous studies have identified that spinal manipulation can directly influence the proprioceptive system (Rogers, 1997; Davis, 2001; Sung et al., 2005; Palmgren et al., 2006; Haavik-Taylor and Bernadette, 2007), e.g. head reposition accuracy (Palmgren et al., 2006), or evoked potentials (Haavik-Taylor and Bernadette,
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2007). Palmgren et al. (2006) demonstrated that spinal manipulation had an impact on proprioceptive sensibility in people with neck pain. Further, Karlberg et al. (1991) and Heikkila¨ and Wenngren (1998) suggested that afferent inputs facilitated by joint manipulation may induce alterations in the proprioceptive stimuli hence affecting postural control. Force platforms are commonly used for the evaluation of the interaction between the lower extremity and the ground. Stabilometry conducted with a force platform is an innocuous, objective, and reproducible method of assessment that can be used in subjects of both sexes, regardless of weight or height, with the aim of obtaining data related to both stability and posture (Nordahl et al., 2000). Therefore, stabilometry can be used for investigating changes in standing stability after the application of any therapeutic procedure (Leardini et al., 1999). Although some previous studies have analysed the effects of spinal manipulation on proprioception, there are few studies investigating the influence of joint manipulations on the proprioceptive system of the extremities (Lo´pez-Rodrı´ guez et al., 2007). Hence, the purpose of this study was to investigate the immediate effects of bilateraltalocrural joint manipulation on standing stability in healthy subjects.
2. Methods 2.1. Subject
120 40 cm, 1600 sensors, and 200 Hz of frequency. The system was comprised of a force platform mounted to the floor. Subjects were asked to stand on the platform in a standardized fashion. Before data collection began, subjects several verbal commands: ‘‘be as still as possible, breathe normally, keep gaze on a fixed point (situated 5 m in front), do not clench the jaw, do not speak, and hold this position until otherwise indicated’’. Individuals maintained their gaze on the fixed reference point during all the assessment. The variables captured were the following: range of X coordinates (coord X ), which represented the range of lateral displacement over the force platform; range of Y coordinates (coord Y ) representing the range of anterioreposterior displacement over the force platform; mean of X coordinates (X mean), that is, the mean of the lateral displacement; mean of Y coordinates (Y mean), i.e. the mean of the anterioreposterior displacement, full length of each displacement, surface area, anterioreposterior velocity (velocity AeP), latero-lateral velocity (velocity LeL), and mean velocity (Fig. 1). 2.3. Reliability study Ten healthy subjects, who were not included in the main analysis, participated in a reliability study. Stabilometric assessment was recorded following the guideline as previously described, and the data were analysed by three independent assessors. Intra-class correlation coefficient (ICC 3,1) showed a high inter-examiner reliability of 0.75 (95% CI 0.7e0.81).
We conducted a randomised single-blind controlled study investigating the effects of bilateral talocrural joint manipulation on standing stability in healthy subjects. Sixty-two healthy volunteers, 16 males and 46 females, aged from 18 to 22 years (mean: 21.35 2.69) agreed to participate, provided informed consent and were included in data analysis. Subjects were excluded if they exhibited the following: (a) alterations of stability (cerebellar syndromes, migraine, impairment of the central nervous system, dizziness); (b) presence of deformities or orthopaedic lesions in the lower extremity; (c) subjects with history of trauma to the lower extremity or lumbar spine; (d) contraindications to the manipulative procedure (ankle joint instability, bone fracture, acute oedema); (e) received treatment of the lower extremity in the previous year; or (f) who reportedly had engaged in strenuous physical activity immediately before the study period.
2.4. Manipulative intervention
2.2. Outcome measures
Healthy subjects were recruited through an announcement at the Universidad de Salamanca, Spain, from March of 2005 to February of 2006. Subjects were asked to not perform any physical activity 24 h prior to participation in the study. Subjects underwent
A stabilometric analysis was performed using a Diagnostic Support Force Platform (Modular electronic baropodometer, Diasu SRL, Italy) with a capture area
An experienced physical therapist performed a distractive (caudal) manipulation directed at the talocrural joint in both extremities. The manipulation was performed with the subject in the supine position. The clinician interlaced both hands over the tibia and talus with thumbs over the posterior aspect of the calcaneus bone. A force was applied in a caudal direction until a slight tension was perceived by the clinician at the talocrural joint. A short distractive manipulative thrust was applied with slight accentuation of the dorsi-flexion vector (Fig. 2). The procedure for this technique was consistent with that previously used by Fryer et al. (2002). Each talocrural joint received only one thrust manipulation. 2.5. Study protocol
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Fig. 1. Stabilometric and centre of gravity assessment.
a physical examination prior to their inclusion on the study. Both weight (Tefal digital balance, precision 0.1 kg) and height (Med control stadiometer precision 0.1 cm) were assessed as anthropometrical variables. Following the physical examination, pre-intervention data were collected by a clinician blind to group assignment. Subjects were positioned over the force platform during 5 min in order to assess pre-intervention data. Stabilometric values from the fifth minute were considered the pre-treatment data and used in the analysis. After pre-treatment measurements were collected, subjects were randomly divided into two groups: an intervention group (n ¼ 32) which received a bilateral talocrural joint
manipulation and a control group (n ¼ 30) which did not receive any intervention. The manipulative technique was applied by a second clinician, who was blinded to preintervention data. Post-treatment data were assessed 5 min after the application of each intervention by the first clinician, who was blind to group allocation. Again, post-intervention data were taken from the fifth minute of the 5-min post-treatment stabilometric record. 2.6. Statistical analysis Data were analysed with the SPSS package (version 12.0). Mean and standard deviations were calculated for each variable. A normal distribution of quantitative data was assessed by means of the KolmogoroveSmirnov test (P > 0.05). Baseline features were compared between groups using the independent t-tests for continuous data, and c2 tests of independence for categorical data. An analysis of covariance (ANCOVA) was used to assess differences between groups with the pre-intervention value as covariant, group as the independent variable and the post-intervention value as dependent variable. The statistical analysis was conducted at a 95% confidence level. A P-value less than 0.05 was considered as statistically significant in all analyses.
3. Results
Fig. 2. Talocrural trust distractive manipulation.
Thirty-two subjects, nine men and 23 women, aged 18e32 (mean age: 21.94 3.36 years) were randomly
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Table 1 Within preepost values of both groups for each outcome measure Control group
Coordinate X (mm) Coordinate Y (mm) X mean (mm) Y mean (mm) Surface (mm2) Length (mm) Velocity AeP (mm/s) Velocity LeM (mm/s) Mean velocity (mm/s)
Experimental group
Pre-intervention
Post-intervention
Pre-intervention
Post-intervention
6.3 7.4 0.001 0.6 57.6 271.3 2.7 3.0 4.5
7.5 8.8 0.6 0.9 87.5 276.8 2.7 3.2 4.6
7.2 8.4 0.1 0.2 85.5 260.3 2.5 3.0 4.4
6.3 6.9 0.4 0.5 52.8 252.4 2.4 2.9 4.2
(1.6) (3.8) (1.3) (2.3) (65.7) (47.2) (0.6) (0.6) (0.8)
(2.7) (4.4) (2.4) (2.6) (83.9) (44.1) (0.6) (0.6) (0.7)
(3.6) (5.3) (1.8) (2.1) (122.3) (50.4) (0.6) (0.7) (0.8)
(2.5) (3.3) (1.4) (1.9) (48.1) (45.7) (0.5) (0.6) (0.7)
Values are expressed as mean standard deviation.
assigned to the intervention group; whereas 30 subjects, seven men and 23 women, aged 18e24 (mean age: 20.73 1.55 years) were assigned to the placebo group. No significant differences for gender, age, or posture measurements were found between both groups at baseline, so it could be assumed that both groups were similar at the start of the study. The ANCOVA found statistically significant differences between groups for some variables. Further, the intrinsic variability of posture data showed that some variables achieved statistical significance. The range of X coordinates and Y coordinates revealed differences between both groups, although it was only significant for anterioreposterior displacements (Table 1). Both the anterioreposterior and lateral displacements were smaller after the manipulative procedure compared to the control intervention. This was also true for the measurement of surface area, which encompasses 95% of such displacements, where the differences were significant both in terms of absolute values (41.6 mm2) and statistically significance (P ¼ 0.02). The mean situation of the displacements, as shown in the X mean and Y mean variables did not exhibit significant differences within the control group. Finally, the variable of displacement length was reduced by 18.4 mm in the experimental group, but differences were not significant (P ¼ 0.06).
Results of this study demonstrated that bilateral talocrural joint manipulation did not modify the standing stability, i.e. behavioural pattern of the projection of the centre of pressure, in healthy subjects. Nevertheless, a trend towards small differences between groups was found, possibly due to the small sample size or intrasubject variability of stabilometric data. Future studies including greater sample sizes should be conducted in order to investigate intra-subject variability of standing balance data. It seems that posture assessment has an intrinsic variability, so we calculated the SEM for all the variables in order to see if group differences could be provoked by an inherent error of the stabilometric data (Table 3). We can see that SEM had significantly lower values than changes obtained after the manipulative procedure
Table 2 Inter-group comparison of both groups with ANCOVA analysis
Table 3 Standard error of measurement of each variable
Coordinate X (mm) Coordinate Y (mm) X mean (mm) Y mean (mm) Surface (mm2) Length (mm) Velocity AeP (mm/s) Velocity LeM (mm/s) Mean velocity (mm/s) a
Liberty grades
P-value of interaction
P-value of ANCOVA
58 58 58 58 58 58 58 58 58
0.4 0.2 0.7 0.2 0.2 0.8 0.4 0.8 0.8
0.06 0.02a 0.6 0.6 0.02a 0.06 0.2 0.07 0.06
Statistically significant different between both groups.
Finally, velocity of the displacements, i.e. anteriore posterior and lateral velocity, did not show significant differences. Nevertheless, mean velocity was closed statistical significance (P ¼ 0.06). Table 1 summarizes pre- and post-intervention data for both groups, whereas Table 2 includes the P-value of the ANCOVA analysis.
4. Discussion
SEM Coordinate X (mm) Coordinate Y (mm) X mean (mm) Y mean (mm) Surface (mm2) Length (mm) Velocity AeP (mm/s) Velocity LeM (mm/s) Mean velocity (mm/s)
0.3 0.6 0.2 0.3 12.6 6.2 0.1 0.1 0.1
Data were taken from pre-intervention data of the whole sample (SD/O sample size).
F. Alburquerque-Sendı´n et al. / Manual Therapy 14 (2009) 75e80
which suggests that these changes were induced by the procedure and not related to an inherent error of the equipment. Nevertheless, with current data we do not know how much does the sway for one subject vary over a period of time (intra-subject variability), so changes in both groups could be also related to this intrinsic variability of posture assessment data. The results of the current study differ from those of previously conducted studies performed on younger populations. Rougier and Caron (1997) found a surface area of 92.8 34.2 mm, X coordinate of 5.1 2.7 mm, and Y coordinate of 9.20 4.65 mm. Gagey and Weber (2001) get 91 mm2 as mean surface area value in healthy populations. The mean of the displacements in X- and Y-axes was close to zero, as it could be expected and supported by others (Gagey and Weber, 2001). Previous studies have found that manipulations are able of modify transmission of proprioceptive input not only at a spinal level (Symons et al., 2000), but also at a cortical level (Haavik-Taylor and Bernadette, 2007). Perry et al. (2001) found a significant increase in the displacement of the centre of pressure after the application of cold, which suggests that afferent inputs from receptors in the ankle or feet could potentially induce changes in standing stability. Perhaps talocrural joint manipulation may induce both, peripheral stimulation of proprioceptive afferents of the ankle joint and leading to enhanced proprioceptive input. It seems that both local and cortical stimulations could be involved in the physiological effects of manipulative techniques on standing stability. Few studies have previously used stabilometric assessment to identify the effects of manipulative interventions. Nevertheless, previous studies that have investigated the effects of talocrural joint manipulations have used similar procedures. Pellow and Brantingham (2001) found an improvement in pain outcomes (algometry, McGill Pain Questionnaire, Numerical Pain Rate Scale) following eight manipulations of the talocrural joint. On the contrary, Fryer et al. (2002) did not identify any change in ankle range of motion following talocrural joint manipulation in healthy subjects. These authors found that joint cavitation only occurred in those subjects who exhibited lower extremity mobility restrictions prior to the intervention, which is in agreement with the findings of Nield et al. (1993). The present study suggests that manipulation of the talocrural joint may induce stabilometric changes, although future studies with greater sample sizes and symptomatic populations are needed. Finally, it seems sensible that the application of manipulative interventions could be combined with exercise training programs. Hess et al. (2001) found that an exercise training program did not modify stabilometric records in subjects with unstable ankles. Blackburn et al. (2000) also failed to report differences in stabilometry
79
in asymptomatic individuals who received both strength and proprioception trainings. Our study has some limitations. First, possibly the sample size did not permit to get statistically differences in some of the analysed variables. Second, it is possible that intra-subject variability of the stabilometric data can also influence in differences found between both groups. Third, it is also possible that the application of a sham-manual procedure instead of no-intervention would be better as control. Future studies should include greater sample sizes and sham-manual procedures as control or placebo group. Acknowledgments We would like to thank to Joshua A. Cleland for the revision of the manuscript. References Blackburn T, Guskiewicz KM, Petschauer MA. Balance and joint stability: the relative contributions of proprioception and muscular strength. J Sport Rehabil 2000;9:315e28. Davis D. Chronic painedysfunction in whiplash-associated disorders. J Manipulative Physiol Ther 2001;24:44e51. Fryer GA, Mudhe JM, McLaughlin PA. The effect of talocrural joint manipulation on range of motion at the ankle. J Manipulative Physiol Ther 2002;6:384e90. Gagey PM, Weber B. Posturologı´ a. Regulacio´n y alteraciones de la bipedestacio´n. Barcelona: Editorial Masson; 2001. Haavik-Taylor H, Bernadette M. Cervical spine manipulation alters sensory-motor integration: a somato-sensory evoked potential study. Clin Neurophysiol 2007;118:391e402. Heikkila¨ H, Wenngren B. Effects of acupuncture, cervical manipulation and NSAID on dizziness of suspected cervical origin. Arch Phys Med Rehabil 1998;79:1089e94. Hess DM, Joyce CJ, Arnold BL, Gansneder BM. Effect of a 4-week agility-training program on postural sway in the functionally unstable ankle. J Sport Rehabil 2001;10:24e35. Karlberg M, Magnusson M, Johansson R. Effects of restrained cervical mobility on voluntary eye movements and postural control. Acta Otolaryngol (Stockholm) 1991;111:664e70. Leardini A, O’Connor JJ, Catani F, Giannini S. Kinematics of the human ankle complex in passive flexion; a single degree of freedom system. J Biomech 1999;32:111e8. Lo´pez-Rodrı´ guez S, Ferna´ndez-de-las-Pen˜as C, AlburquerqueSendı´ n F, Rodrı´ guez-Blanco C, Palomeque-del-Cerro L. Immediate effects of manipulation of the talocrural joint on stabilometry and baropodometry in patients with ankle sprain. J Manipulative Physiol Ther 2007;30:186e92. Miralles RC, Heras C. Introduccio´n a la biomeca´nica clı´ nica del aparato locomotor. In: Miralles R, Miralles I, editors. Biomeca´nica clı´ nica de los tejidos y lar articulaciones del aparato locomotor. 2a ed. Barcelona: Masson; 2005. p. 3e14. Nield S, Davis K, Latimer J, Maher CD, Adams R. The effects of joint manipulation on range of motion at the ankle joint. Scan J Rehabil Med 1993;25:161e6. Nordahl SH, Aasen T, Dyrkorn BM, Eldsvik S, Molvaer OI. Static stabilometry and repeated testing in a normal population. Aviat Space Environ Med 2000;71:889e93. Palmgren PJ, Sandstro¨m PJ, Lundqvist FJ, Heikkila¨ H. Improvement after chiropractic care in cervico-cephalic kinesthetic sensibility and
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subjective pain intensity in patients with non-traumatic chronic neck pain. J Manipulative Physiol Ther 2006;29:100e6. Pellow JE, Brantingham JW. The efficacy of adjusting the ankle in the treatment of subacute and chronic grade I and grade II ankle inversion sprains. J Manipulative Physiol Ther 2001;1:17e24. Perry SD, Santos LC, Patla AE. Contribution of vision and cutaneous sensation to the control of centre of mass (COM) during gait termination. Brain Res 2001;913:27e34. Rogers RG. The effects of spinal manipulation on cervical kinaesthesia in patients with chronic neck pain: a pilot study. J Manipulative Physiol Ther 1997;20:80e5.
Rougier P, Caron O. Effet des informations visuelles et plantaires sur le controˆle postural orthostatique. In: Lacour M, Gagey PM, Weber B, editors. Posture et enviroment. Montpellier, Sauramps Medical; 1997. p. 125e39. Sung PS, Kang YM, Picar JP. Effect of spinal manipulation duration on low threshold mechanoreceptors in lumbar paraspinal muscles. Spine 2005;30:115e22. Symons BP, Herzog W, Leonard T, Nguyen H. Reflex responses associated with activator treatment. J Manipulative Physiol Ther 2000;23:155e9. Villeneuve P. Le pied humain organe de la posture orthostatique. Kinesither Sci 1990;294:47e51.
Available online at www.sciencedirect.com
Manual Therapy 14 (2009) 81e87 www.elsevier.com/math
Original article
Quantification of shoulder tightness and associated shoulder kinematics and functional deficits in patients with stiff shoulders Jing-lan Yang a, Shiau-yee Chen b, Chein-wei Chang a, Jiu-jenq Lin c,d,* a
Department of Physical Medicine and Rehabilitation, National Taiwan University Hospital, 7 Chun-Shan S Road, Taipei, Taiwan b Department of Internal Medicine, Taipei Medical University-Municipal Wan Fang Hospital, Taipei, Taiwan c School and Graduate Institute of Physical Therapy, College of Medicine, National Taiwan University, 3 F, 17, Xu-Zhou Road, Taipei 100, Taiwan d Department of Physical Medicine and Rehabilitation, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei, Taiwan Received 26 April 2007; received in revised form 17 October 2007; accepted 21 November 2007
Abstract Measurement of anterior/posterior shoulder tightness, humeral external/internal rotation range of motion (ROM), scapular upward rotation/tipping ROM, and functional limitations were made in 46 patients with unilateral stiff shoulders (SSs) using a clinical measurement (shoulder tightness), a three-dimensional electromagnetic tracking device (shoulder ROM), and self-reports of function. Patients with SSs in their dominant shoulder demonstrated statistically greater posterior shoulder tightness compared to nondominant shoulder. Control dominant shoulders demonstrated decreased internal ROM as compared with control nondominant shoulders ( p ¼ 0.021). In SSs, significant relationships were found between humeral internal rotation ROM and posterior shoulder tightness (R ¼ 0.49, p < 0.0005), humeral external rotation ROM and anterior shoulder tightness (R ¼ 0.59, p ¼ 0.0002), scapular tipping and anterior shoulder tightness (R ¼ 0.57, p ¼ 0.004). Specifically, in patients with dominant SSs, posterior shoulder tightness and functional limitation were related (R ¼ 0.56, p ¼ 0.002). In patients with dominant involved shoulders, emphasise on posterior tightness stretch may improve functional ability directly. In addition to stretching program in patients with SSs, internal rotation ROM of control dominant shoulder is also important to consider in the rehabilitation of patients with SSs. Ó 2007 Elsevier Ltd. All rights reserved. Keywords: Stiff shoulder; Tightness; Humeral rotation; Scapula
Stiff shoulder (SS) is a common health problem in various patient populations. SS is characterized by pain and functional restriction of both active and passive shoulder motions (Reeves, 1975; Wadsworth, 1986; Murnaghan 1990). The prevalence of SS in populations has been estimated to be 2 and 5% (Lubiecki and Carr, 2007). Diabetic patients have a higher incidence (10%) * Corresponding author. School and Graduate Institute of Physical Therapy, College of Medicine, National Taiwan University, 3 F, 17, Xu-Zhou Road, Taipei 100, Taiwan. Tel.: þ886 2 33228126; fax: þ886 2 23313598. E-mail address:
[email protected] (J. Lin). 1356-689X/$ - see front matter Ó 2007 Elsevier Ltd. All rights reserved. doi:10.1016/j.math.2007.11.004
than the general population (Bridgman, 1972). SS has been divided into two types: ‘‘idiopathic frozen shoulder’’ and ‘‘post-traumatic SS’’ (Lundberg, 1969; Griggs et al., 2000). Idiopathic contracture and loss of compliance of the glenohumeral joint capsule results in an idiopathic frozen shoulder, while after an injury, soft tissue contracture associated with the glenohumeral joint results in a post-traumatic SS. Specifically, adhesive capsulitis (Murnaghan, 1990) decreased capsular volume (Mao et al., 1997; Vermeulen et al., 2000), capsular contractions (Bunker, 1997), rotator interval thickening and fibrosis (Pearsall et al., 1999), and subscapularis tendon
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thickening (Pearsall et al., 1999) have been reported by arthography and arthoscopy. Although multiple factors are related to SS, the manifestation of shoulder tightness is thought to be correlated to altered glenohumeral movements. Cyriax (1978) proposed that tightness in a shoulder joint capsule would restrict motion in a predictable pattern, a capsular pattern in which external rotation is more limited than abduction, which in turn is more limited than internal rotation. Other authors have indicated that posterior shoulder tightness is significantly correlated with humeral internal rotation range of motion (ROM) loss in patients with shoulder impingement (Harryman et al., 1990; O’Brien et al., 1990; Warner et al., 1990). Specifically, Harryman et al. (1990) stated that asymmetrical tightness of the shoulder capsule, rather than ligament laxity, affects glenohumeral translations, thus influencing ROM of the shoulder. Clinically, capsular stretching exercises as well as mobilization (manipulation) treatments are thought to decrease shoulder capsule tightness and thus result in improvement of shoulder motion (Griggs et al., 2000; Vermeulen et al., 2000). Asymmetrical tightness of the shoulder is assumed to result in loss of ROM in patients with SSs, subsequently decreasing functional performance. The purpose of this study was to document anterior/ posterior shoulder tightness with clinical measurement and characterize relationships between tightness and associated shoulder kinematics and functional deficits in patients with SSs.
1. Materials and methods 1.1. Subjects Forty-six patients suffering from unilateral SS (22 male, 24 female) between the ages of 48 and 85 (mean ¼ 58.1, SD ¼ 16.3) years agreed to have Table 1 Patient characteristics Characteristics
Dominant shoulder involved (N ¼ 24)
Non-dominant shoulder involved (N ¼ 22)
Gender male (female) Age (yrs) Weight (kg) Height (cm) Duration of symptoms, range (m) FLEX-SF self-report (normal: 50/50)a
10 (14) 58.0 10.1 61.3 4.2 155.3 7.8 7.8 4.1, 3e36
12 (10) 54.7 12.8 68.9 12.4 164.9 9.3 6.5 4.2, 3e16
28.6 5.2
37.9 7.6
Patients were diagnosed as adhesive capsulitis (N ¼ 32), rotator cuff injury (N ¼ 14). a The Flexilevel scale of shoulder function (FLEX-SF) was used to assess the functional status of the shoulder.
measurements taken as part of a routine clinical examinations. The affected shoulders (24 dominant shoulders and 22 nondominant shoulders) of the 46 patients were tested. Descriptive data of the subjects’ characteristics are summarized in Table 1. The inclusion criteria of patients with SSs were: (1) a limited ROM of a shoulder joint (ROM losses of 25% or greater compared with the noninvolved shoulder in at least two of the following shoulder motions: glenohumeral flexion, abduction, or internal/external rotation), and (2) pain and stiffness in the shoulder region lasting for at least three months. Exclusion criteria were a history of (1) increased pain and/or stiffness in the past month, (2) surgery on the particular shoulder, (3) rheumatoid arthritis, (4) stroke with residual shoulder involvement, or (5) fracture of the shoulder complex. All subjects reviewed and signed the hospital-approved human subject informed consent document before participating. Additionally, the ethics of the whole study were approved by the hospital. Subsequently, the subjects were examined to determine the ROM, pain, and functional status of their affected shoulders. 1.2. Equipment A hand-held standard universal goniometer was used to measure the range of the shoulder joint motion. This goniometer was a double-armed, full circle protractor made of transparent plastic. Additionally, a fluid type inclinometer (Isomed, Portland, Oregon) was used to assess cross-chest and below-chest shoulder ROM. The inclinometer resembles a flat goniometer with 360 degrees of graduation marked in single-degree increments on the circumference. We determined the angle by comparing the location of the arm on the inside of the inclinometer with the degree markings around the circumference. During the measurement, the inclinometer was held in a vertical position. Thus, the arm (gravity) remained in the downward position, indicating the change in limb position. The FASTRAK 3-D electromagnetic motioncapturing system (Polhemus Inc., Colchester, VT, USA) was used to detect shoulder ROM. Three sensors for the system were attached to the bony landmarks with adhesive tape. Each sensor was 2.3 cm in length, 2.8 cm in width, 1.5 cm in height, and weighed 17 g. One sensor was attached to the sternum, and one sensor was attached to the flat bony surface of the scapular acromion with adhesive tape. The third sensor was attached to the distal humerus with Velcro straps. Additionally, a fourth sensor, attached to a stylus, was used to digitize palpated anatomical coordinates (bony landmarks: sternal notch, xyphoid process, seventh cervical vertebra, eighth thoracic vertebra, acromioclavicular joint, root of the spine of the scapula, inferior angle of the scapula, lateral epicondyle, and medial epicondyle; glenohumeral
J.-l. Yang et al. / Manual Therapy 14 (2009) 81e87
joint rotation center was operationalized by the anterior humeral joint and posterior humeral joint). Within a 76-cm source-to-sensor separation, the RMS system accuracy is 0.15 degree for orientation and 0.3e0.8 mm for position. 1.3. Measurement of posterior and anterior shoulder tightness Lin and Yang (2006) have previously described the measurement of posterior and anterior shoulder tightness (Fig. 1). For the assessment of posterior and anterior shoulder tightness, horizontal flexion ROM (cross-chest adduction) and horizontal extension ROM (below-chest abduction) were measured, respectively, in the supine position on a plinth with an inclinometer. First, the humerus was grasped distal to the epicondyles of the elbow and moved into a cross-chest adduction or below-chest abduction with neutral rotation until the movement ceased (firm end-feel), indicating the end of shoulder tissue
Fig. 1. Illustration of the shoulder tightness measurement method.
83
flexibility. During the test, the scapula was palpated at the lateral border and stabilized by hand. The test was aborted and restarted if the subject was unable to relax or if the scapula could not be stabilized effectively. The horizontal adduction ROM or horizontal abduction ROM being measured by the inclinometer by a tester and recorded by a recorder. The recorder placed the inclinometer parallel to the humerus next to the medial epicondyle. The measured angles indicated the amount of flexibility of the posterior and anterior shoulder tissues. A greater angle indicated more flexibility of the shoulder tissue. This measurement was taken bilaterally. Additionally, the measurers were blinded to whether the measurement was of the dominant/nondominant-arm or the stiff/ nonstiff shoulder. 1.4. Measurement of humeral and scapular ROM Data collection of humeral and scapular ROM was performed as outlined in previous investigations (Lin et al., 2005a,b). Recordings started with the subject in a sitting position, the arms relaxed at the sides. Kinematics was collected for 5 s in this resting seated posture. Subjects were then asked to perform full active ROM in three tests: abduction in the scapular plane, hand-to-neck and hand-to-scapula. Hand-to-neck and hand-to-scapula tests represented function-related tests (Yang and Lin, 2006). For the abduction in the scapular plane, subjects were guided to remain in the scapular plane oriented 40 degrees anterior to the coronal plane (Ludewig and Cook, 2000). Three replicated movements were performed in each test to the maximum possible active motions of the arms. The order of tests was randomized. Humeral orientation relative to the scapula was described using an Euler angle sequence in which the first rotation represented the plane of elevation, the second rotation defined the amount of elevation, and the third rotation described the amount of axial rotation. Scapular orientation relative to the thorax was described using an Euler angle sequence of rotation about Zs (protraction/retraction), rotation about Y0 s (downward /upward rotation), and rotation about X00 s (posterior/anterior tipping). All kinematic variables from the three trials of each test were used in the following analyses. For the hand-to-neck and hand-to-scapula tests, the peak external rotation ROM and peak interior rotation ROM were used, respectively. For the abduction in the scapular plane test, the peak scapular upward rotation and peak scapular tilt were used. The above measurement was taken bilaterally. Additionally, all patients were asked to complete selfreport scales for evaluating their functional status of the shoulder, the self-reported Flexilevel Scale of Shoulder Function (FLEX-SF) (Cook et al., 2003). This scale covers the entire continuum assessment of shoulder
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functions and has been satisfactorily tested for appropriate psychometric properties of reliability, validity, and responsiveness to clinical change. Scores were recorded from 1, with the most limited function, to 50, without any limited function in the subject. 1.5. The reliability and validity of tightness measurement Lin and Yang (2006) have previously described the intratester and intertester reliability and validity of measuring posterior and anterior shoulder tightness. The intratester and intertester reliabilities for shoulder tightness measurements were good (intratester ICC ¼ 0.84 and 0.91; intertester ICC ¼ 0.82 and 0.89). The validation testing was performed on patients with SSs. Patients with SSs are a population known to have a decrease in humeral internal/external rotation ROM and shoulder tightness in their affected arms (Reeves, 1975; Wadsworth, 1986; Vermeulen et al., 2000). In their study, patients with SSs showed significant relationships between decreased humeral internal rotation ROM and posterior shoulder tightness (R2 ¼ 0.448), as well as between decreased humeral external rotation ROM and anterior shoulder tightness (R2 ¼ 0.499). 1.6. Statistical analysis To characterize shoulder tightness and associated shoulder kinematics and functional deficits in SSs, two-factor mixed ANOVA models with factors of two sides (involved and control shoulders) and group (subjects with dominant or nondominant involved shoulders) were calculated. Dependent variables included anterior/posterior tightness, kinematic variables (humeral internal/external ROM, scapular upward rotation/tipping ROM), and functional scores. Bonferroni follow-up analyses were used for multiple pair-wise comparisons. A Pearson’s productemoment correlation coefficient was used to determine whether a relationship existed between anterior/posterior tightness, humeral internal/external ROM, scapular upward rotation/ tipping ROM, and functional limitation. The SPSS for Windows statistical analysis program (SPSS Inc., Chicago, USA) was used, and alpha was set at p < 0.05.
2. Results Table 2 presents measurements of anterior tightness, posterior tightness, humeral external rotation/internal rotation ROM, and scapular upward rotation/tipping ROM bilaterally in patients with SSs. Patients with SSs in either their dominant or nondominant shoulders demonstrated a statistically significant greater anterior/ posterior shoulder tightness ( p < 0.005), loss of humeral internal/external rotation ROM ( p < 0.005), and loss of scapular upward rotation/tipping ROM ( p < 0.005) as compared with controls (Table 2). Patients with SSs in their dominant shoulder demonstrated a statistically greater posterior shoulder tightness as compared with SSs in the nondominant shoulder ( p ¼ 0.044) (Fig. 2). Additionally, control dominant shoulders demonstrated decreased internal ROM as compared with control nondominant shoulders ( p ¼ 0.021). In both dominant and nondominant SSs, significant relationships were found between humeral internal rotation ROM and posterior shoulder tightness (R ¼ 0.49, p < 0.0005), humeral external rotation ROM and anterior shoulder tightness (R ¼ 0.59, p ¼ 0.0002), scapular tipping ROM and anterior shoulder tightness (R ¼ 0.57, p ¼ 0.004) in patients (Table 3). Specifically, in patients with dominant SSs, posterior shoulder tightness and functional limitation were related (R ¼ 0.56, p ¼ 0.002). These correlations are not particularly strong, and the relationships between the variables may exist due to other factors not studied here. Alternatively, no significant relationship was found between humeral external rotation ROM and posterior shoulder tightness (R ¼ 0.24, p ¼ 0.065), humeral internal rotation ROM and anterior shoulder tightness (R ¼ 0.09, p ¼ 0.496), scapular upward rotation and anterior/ posterior tightness (R ¼ 0.35 and 0.14, p > 0.05), and anterior shoulder tightness and functional disabilities (R ¼ 0.11, p ¼ 0.378) in patients with SSs.
3. Discussion ROM deficits have been documented in patients with SSs (Reeves, 1975; Wadsworth, 1986; Warner et al.,
Table 2 Shoulder tightness and ROM for patients with SSs (mean standard error of measurement) SSs
Anterior tightness (degrees)
Posterior tightness (degrees)
ROM of humerus Internal rotation (degrees)
External rotation (degrees)
ROM of Scapula Upward rotation (degrees)
Tipping
Dominant Involved (N ¼ 24) Control (N ¼ 22)
12.1 6.0 27.2 4.2
13.4 9.3 22.6 4.2
23.3 13.2 77.4 12.6
38.5 19.4 86.4 5.3
34.4 8.5 43.9 5.8
12.3 6.7 24.2 4.8
Nondominant Involved (N ¼ 22) Control (N ¼ 24)
12.7 7.6 27.5 7.0
10.7 7.6 27.1 4.7
20.6 13.2 86.5 4.3
33.1 23.9 85.5 12.3
33.4 8.5 43.1 5.2
11.6 6.7 24.1 5.2
85
J.-l. Yang et al. / Manual Therapy 14 (2009) 81e87 70 Dominant arm involved Nondominant arm involved 60
Magnitude (degrees)
50
40
30
20
10
0
Anterior tightness Posterior tightness Internal rotation
External rotation
Scapular upward rotation
Scapular tipping
Measurement Fig. 2. Comparison of ROM and posterior/anterior tightness deficits of patients with dominant-arm involved and nondominant-arm involved SSs.
1990; Griggs et al., 2000; Rundquist et al., 2003). It has been postulated that loss of humeral internal rotation and external rotation of the involved shoulder are the result of posterior shoulder tightness and anterior shoulder tightness, respectively (Warner et al., 1990; Tyler et al., 1999, 2000; Rundquist et al., 2003). The results of the present study support this assumption. Significant relationships were found between humeral internal rotation ROM and posterior shoulder tightness, as well as humeral external rotation ROM and anterior shoulder tightness. In addition, deficits in upward rotation/tipping of the scapula were found in patients with SSs. Particularly, significant relationship was also found between scapular tipping and anterior shoulder tightness. Further, patients with SSs in their nondominant shoulders had impaired internal rotation of their control dominant shoulders. This finding is important because this phenomenon may be related to further development of bilateral shoulder impairments. Functional limitations and loss of motion in patients with SSs have been thought to be due to tightness in a joint
capsule, and stretching/mobilization has been advocated (Murnaghan, 1990; Warner et al., 1990; Vermeulen et al., 2000; Rundquist et al., 2003). Specifically, the relationship between special areas of shoulder tightness and functional limitations has long been recognized clinically (Harryman et al., 1990; Tyler et al., 1999, 2000). However, evidence to support this speculation is limited. Although Tyler et al. (1999, 2000) demonstrated a significant relationship between limitation of humeral internal rotation ROM and posterior capsule tightness in patients with shoulder impingement, the correlation between functional limitation and these two measures was not investigated. The current study showed significant correlations between the self-report of functional limitation and posterior shoulder tightness. Tyler et al. (2000) found that patients with impingement in their dominant arms exhibit a decreased humeral internal rotation ROM and increased tightness in the posterior shoulder. In agreement with their study (Tyler et al., 2000), the current study demonstrated that patients with SSs exhibited more humeral internal
Table 3 Relationships between shoulder tightness and ROM for patients with SSs
Anterior shoulder tightness Posterior shoulder tightness *p < 0.001.
Humeral external rotation
Humeral internal rotation
Scapular upward rotation
Scapular tipping
R ¼ 0.59* R ¼ 0.24
R ¼ 0.09 ) R ¼ 0.49
R ¼ 0.35 R ¼ 0.14
R ¼ 0.57 R ¼ 0.19
)
Functional limitation R ¼ 0.11 R ¼ 0.56*
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J.-l. Yang et al. / Manual Therapy 14 (2009) 81e87
rotation loss accompanied by posterior shoulder tightness in both dominant and nondominant involved shoulders. Thus, potential impingement in patients with SSs may lead to the decreased functional performance indicated by self-reports. Additionally, the anteriorly tipped position in subjects with anterior shoulder tightness would place the anterior acromion in earlier closeness to the rotator cuff tendons and increase the potential of impingement (Ludewig and Cook, 2000). The current study also supports this assumption. Significant relationship between scapular tipping and anterior shoulder tightness in our study highlighted that stretch of anterior shoulder tightness may provide prevention of potential scapular impingement syndrome in patients. Patients with SSs are believed to have tightness at different areas of the joint capsule and/or other soft tissues. Despite the capsular pattern proposed by Cyriax (1978), Rundquist et al. (2003) measured three-dimensional humeral motion in subjects with SSs and indicated that no consistent capsular pattern of restriction of shoulder motion exists. The tightness and restricted rotation ROM of the shoulder joint in our subjects supported this proposition. In the current investigation, the patterns of decreased rotation ROM of shoulder and degree of shoulder tightness were inconsistent in our patients. Thus, different treatment intervention emphases, such as joint mobilization and/or stretching, for each specific individual should be advocated. Tyler et al. (1999, 2000) suggested that distinguishing capsule tightness from other soft tissue tightness might be achieved by assessing humeral ROM in different degrees of shoulder abduction. Patients who have intrinsic posterior capsule tightness will have more limitation of motion in 90 degrees of abduction than they will in the arm-by-side position because of the increased tension on the capsule in 90 degrees of abduction. The limitations of the current study should be noted. The direct relationship between humeral motion (internal/external rotations)/scapular motion (tipping) and shoulder tightness cannot be assumed. However, loss of humeral internal/external rotation ROM as well as scapular tipping ROM is an adaptive change related to posterior/anterior shoulder tightness, and stretching has been advocated (Johansen et al., 1995; Tyler et al., 1999, 2000). Another limitation of our study is the sample population and proportion of patient diagnoses. The study sample may not fully represents the spectrum of patients with SSs. The restricted subacute clinical condition of our subjects also limits the generalizability outside of this subacute condition in patients with SSs. The role that mobilizing and/or stretching the capsule plays in restoring shoulder ROM has yet to be determined. Longitudinal investigations will be important to further validate the clinical use of this measurement. Quantifying shoulder tightness will facilitate patient
classification and improve the utility of stretching/mobilization, therapeutic modalities, and exercises.
4. Conclusions Shoulder tightness, limited humeral and scapular ROM, and functional deficits were present in subjects with SSs. Humeral internal and external rotation ROM had moderate relationships with posterior and anterior shoulder tightness, respectively, in this population. Scapular tipping ROM was significantly correlated with anterior shoulder tightness. In addition to stretching program in patients with SSs, internal rotation ROM of control dominant shoulder is also important to consider in the rehabilitation of patients with SSs.
References Bridgman JF. Periarthritis of the shoulder and diabetes mellitus. Annals of the Rheumatic Diseases 1972;31:69e71. Bunker TD. Frozen shoulder: unravelling the enigma. Annals of the Royal College of Surgeons of England 1997;79:210e3. Cook KF, Roddey TS, Gartsman GM, Olson SL. Development and psychometric evaluation of the Flexilevel scale of shoulder function. Medical Care 2003;41:823e35. Cyriax J. Diagnosis of soft tissue lesions. In: Textbook of Orthopedic Medicine, vol. 1. New York: Macmillan Publishing; 1978. Griggs SM, Ahn A, Green A. Idiopathic adhesive capsulitis: a prospective functional outcome study of nonoperative treatment. Journal of Bone and Joint Surgery American Volume 2000;82:1398e407. Harryman II DT, Sidles JA, Clark JM, et al. Translation of the humeral head on the glenoid with passive glenohumeral motion. Journal of Bone and Joint Surgery American Volume 1990;72: 1334e43. Johansen RL, Callis M, Potts J, Shall LM. A modified internal rotation stretching technique for overhand and throwing athletes. Journal of Orthopaedic and Sports Physical Therapy 1995;21: 216e9. Lin JJ, Hanten WP, Olson SL, et al. Functional activity characteristics of individuals with shoulder dysfunctions. Journal of Electromyography and Kinesiology 2005a;15:576e86. Lin JJ, Hanten WP, Olson SL, et al. Functional activities characteristics of shoulder complex movements: exploration with a threedimensional electromagnetic measurement system. Journal of Rehabilitation Research and Development 2005b;42:199e210. Lin JJ, Yang JL. Reliability and validity of shoulder tightness measurement in patients with stiff shoulders. Manual Therapy 2006;11:146e52. Lubiecki M, Carr A. Frozen shoulder: past, present, and future. Journal of Orthopaedic Surgery 2007;15:1e3. Ludewig PM, Cook TM. Alterations in shoulder kinematics and associated muscle activity in people with symptoms of shoulder impingement. Physical Therapy 2000;80:276e91. Lundberg BJ. The frozen shoulder: clinical and radiographical observations. The effect of manipulation under general anesthesia. Structure and glycosaminoglycan content of the joint capsule. Local bone metabolism. Acta Orthopaedica Scandinavica Supplementum 1969;119:1e59. Mao C, Jaw W, Cheng H. Frozen shoulder: correlation between the response to physical therapy and follow-up shoulder arthrography. Archives of Physical Medicine and Rehabilitation 1997;78:857e9.
J.-l. Yang et al. / Manual Therapy 14 (2009) 81e87 Murnaghan JP. Frozen shoulder. In: Rockwood CA, Frederick A, Matsen III, editors. The Shoulder. Philadelphia: WB Saunders Company; 1990. p. 837e61. O’Brien SJ, Neves MC, Arnoczky SP, et al. The anatomy and histology of the inferior glenohumeral ligament complex of the shoulder. American Journal of Sports Medicine 1990;18:449e56. Pearsall AW, Osbahr DC, Speer KP. An arthroscopic technique for treating patients with frozen shoulder. Arthroscopy 1999;15:2e11. Reeves B. The natural history of the frozen shoulder syndrome. Scandinavian Journal of Rheumatology 1975;4:193e6. Rundquist PJ, Anderson DD, Guanche CA, Ludewig PM. Shoulder kinematics in subjects with frozen shoulder. Archives of Physical Medicine and Rehabilitation 2003;84:1473e9. Tyler TF, Nicholas SJ, Roy T, Gleim GW. Quantification of posterior capsule tightness and motion loss in patients with shoulder impingement. American Journal of Sports Medicine 2000;28:668e73.
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Tyler TF, Roy T, Nicholas SJ, Gleim GW. Reliability and validity of a new method of measuring posterior shoulder tightness. Journal of Orthopaedic and Sports Physical Therapy 1999; 29:262e9. Vermeulen HM, Obermann WR, Burger BJ, Kok GJ, Rozing PM, van Den Ende CH. End-range mobilization techniques in adhesive capsulitis of the shoulder joint: a multiple-subject case report. Physical Therapy 2000;80:1204e13. Wadsworth CT. Frozen shoulder. Physical Therapy 1986;66:1878e83. Warner JJ, Micheli LJ, Arslanian LE, Kennedy J, Kennedy RL. Patterns of flexibility, laxity, and strength in normal shoulders and shoulders with instability and impingement. American Journal of Sports Medicine 1990;18:366e75. Yang JL, Lin JJ. Reliability of function-related tests in patients with shoulder pathologies. Journal of Orthopaedic and Sports Physical Therapy 2006;36:572e6.
Available online at www.sciencedirect.com
Manual Therapy 14 (2009) 88e100 www.elsevier.com/math
Original article
Primary care clinicians use variable methods to assess acute nonspecific low back pain and usually focus on impairments Peter M. Kent a,b,*, Jennifer L. Keating c, Nicholas F. Taylor d a Monash Department of Clinical Epidemiology at Cabrini Hospital, Victoria, Australia Department of Epidemiology & Preventive Medicine, Faculty of Medicine, Nursing & Health Sciences, Monash University, Victoria, Australia c Department of Physiotherapy, School of Primary Health Care, Faculty of Medicine, Nursing & Health Sciences, Monash University, Victoria, Australia d School of Physiotherapy, Faculty of Health Sciences, La Trobe University, Victoria, Australia b
Received 22 December 2006; received in revised form 11 June 2007; accepted 2 December 2007
Abstract This study investigated the assessment of acute (<12 weeks duration) nonspecific low back pain (NSLBP) by primary care clinicians. The aims were to determine the methods used, whether methods differ across professional disciplines, and the extent to which clinicians assess across domains of health. Survey data were gathered from 651 primary care clinicians from six professional disciplines (Physiotherapy, Manipulative Physiotherapy, Chiropractic, Osteopathy, General Medicine, and Musculoskeletal Medicine). Descriptive statistics (proportions and frequency of use distributions) were used to describe assessment technique use, ManneWhitney U tests were used to determine between-discipline differences in the use of each assessment technique, and Bonferroni-adjusted inferential confidence intervals were constructed to allow visual comparison of the use of assessment techniques from five health domains. The results indicate that the methods used by different professional disciplines to assess NSLBP vary considerably, as 44 out of 48 assessment techniques showed significantly different utilisation rates across professions. Furthermore, assessment across domains of health in this condition was variable, as clinicians commonly assess physical impairments and pain and less commonly assess activity limitation and psychosocial function (100% of clinicians very frequently or often assess physical impairment, 99% [95%CI 98e100%] assess pain, 21% [95%CI 15e27%] assess activity limitation, and 7% [95%CI 3e11%] assess psychosocial function). Adoption of greater standardisation of assessment by clinicians may require demonstration of the capacity of this standardisation to improve patient outcomes. Ó 2008 Elsevier Ltd. All rights reserved. Keywords: Low back pain; Diagnosis; Primary health care; Rehabilitation; Disability evaluation
1. Background Approximately 80% of low back pain (LBP) in primary care remains a diagnostic enigma and is commonly labelled nonspecific low back pain (NSLBP) (Spengler and David, 1985; Deyo et al., 1992). In contrast, specific * Corresponding author. Monash Department of Clinical Epidemiology at Cabrini Hospital, 183 Wattletree Road, Malvern, Victoria 3144, Australia. Tel.: þ61 3 9508 1589; fax: þ61 3 9508 1368. E-mail address:
[email protected] (P.M. Kent). 1356-689X/$ - see front matter Ó 2008 Elsevier Ltd. All rights reserved. doi:10.1016/j.math.2007.12.006
LBP is caused by identifiable pathology, such as neurocompression, cancer, infection, fracture and metabolic disorders. Optimal treatment strategies for NSLBP remain uncertain. Some have argued that NSLBP is heterogenous and comprises a number of discrete subgroups for which subgroup-specific treatment could optimise outcomes (Maitland, 1986; McKenzie, 1987; Binkley et al., 1993; Hall et al., 1994; Delitto et al., 1995; Leboeuf-Yde et al., 1997; Newton et al., 1997; Petersen et al., 2003), and others have argued that NSLBP is homogenous (Indahl, 1995; Indahl et al.,
P.M. Kent et al. / Manual Therapy 14 (2009) 88e100
1998; Zusman, 1998; Bogduk, 2000b). Of Australian primary care clinicians who responded to a recent survey (Kent and Keating, 2004), 74% thought that it is possible to recognize NSLBP subgroups, and 93% treat NSLBP differently based on patterns of symptoms and signs. Though these beliefs and practices varied across professional disciplines, for clinicians who believe NSLPB to be heterogenous, clinical assessment is important as it informs the classification of patients into subgroups. International clinical guidelines for acute LBP typically advocate diagnostic triage into specific LBP and NSLBP (Bigos et al., 1994; Accident Compensation Commission, 1999; Royal College of General Practitioners, 1999; Australian Acute Musculoskeletal Pain Guidelines Group, 2004). However, these guidelines have not accommodated the notion of subgroup-specific clinical assessment, as evidence of the efficacy of subgroup-specific treatment is recent (Delitto et al., 1995; Flynn et al., 2002; Childs et al., 2004; Long et al., 2004; Brennan et al., 2006). Therefore, the assessment recommended in these guidelines typically only extends to testing for symptoms and signs of serious pathology (red flags), neurocompression and psychosocial risk factors for poor outcome (yellow flags). As most primary care clinicians believe NSLBP is a number of subgroups but share little agreement regarding the symptoms and signs that identify these subgroups (Kent and Keating, 2005), there is likely to be considerable variability in the methods clinicians use to assess NSLBP and uncertainty regarding best practice. Ill health affects many aspects of life, and it has been argued that patient evaluation should include assessment across domains such as physical impairment, pain, activity limitation and participation in society (World Health Organisation, 1980, 2001; Deyo et al., 1998). Little is known regarding the domains that are commonly considered in the clinical assessment of NSLBP. Therefore, the main aim of this research was to describe the methods that primary care clinicians currently use to assess NSLBP and to investigate whether these assessment practices differ across professional disciplines. A secondary aim was to investigate the extent to which clinicians assess across domains of health. This study focuses on assessment of acute LBP (defined as an episode of pain of <12 weeks duration). Acute LBP displays clinical characteristics and relationships between assessment domains that differ from those that have been reported in chronic LBP (>12 weeks duration) (Philips and Grant, 1991; Fritz et al., 2001).
2. Methods 2.1. Survey A survey of Australian primary care clinicians was conducted to assess NSLBP beliefs and practices. Details
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of the survey design, method, response, responder demographics and the views of clinicians regarding NSLBP heterogeneity have been published (Kent and Keating, 2004). The survey also collected data on the clinical reasoning processes that clinicians use to classify NSLBP into subgroups, the results of which have also been published (Kent and Keating, 2005). Clinicians were also asked to indicate the methods that they use to assess acute NSLBP, and responses to that component of the survey are the subject of this report. Briefly, a questionnaire was mailed to 200 randomly selected clinicians from each of these six primary care disciplines: Chiropractors, General Medical Practitioners (GPs), Manipulative Physiotherapists, Musculoskeletal Medicine Practitioners, Osteopaths, and Physiotherapists. Sample size calculations were based upon a nominal 50% response rate and aimed to achieve a withindiscipline power of 10% with 95% confidence (Cochrane, 1977) and the capacity to detect differences across professional groups of 20% with at least 80% power (Altman, 1991). For a more detailed description of the survey method, see Kent and Keating (2004). The survey included the question ‘‘Which examination tests do you use to assess (in the first few consultations) a new acute LBP patient? They may have pain radiation into the sacroiliac/buttock region but have no neurological or radicular symptoms and no serious pathology’’. This question was followed by a list of 48 assessment techniques (Fig. 1). Clinicians could also nominate unlisted assessment techniques. The response options for each assessment technique were arbitrarily defined as: Very frequently (100e61% of the time), Often (60e31%), Sometimes (30e1%), Never (0%), Don’t know the test. The assessment techniques listed were those with reported reliability and some evidence of validity, and those commonly used in practice but not yet formally examined. The process of devising a comprehensive list of items to be included in the questionnaire involved consultation with experienced clinicians, academics (Kent and Keating, 2004) and evidence from expert opinion in the literature (McKenzie, 1979; Maitland, 1986; Phillips et al., 1986; Quebec Task Force on spinal disorders, 1987; Deyo et al., 1992; Binkley et al., 1993; Schonheinz, 1995; Riddle, 1997, 1998; van Tulder et al., 1997; Fritz et al., 2001). It was not possible, nor desirable, to canvass information on every NSLBP assessment technique in the literature. The intention was to canvass information only on those assessment techniques most commonly used, most commonly recommended, or for which there was evidence of clinical utility. Although the term ‘disability’ had been recently superceded by ‘activity limitation’ (World Health Organisation, 2001), the term ‘disability’ was used in the questionnaire, as it was considered likely that potential respondents were more familiar with this term at the time of the survey.
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P.M. Kent et al. / Manual Therapy 14 (2009) 88e100
Low-back pain assessment survey Thank you for completing this questionnaire, which seeks to gather information about the assessments that Australian primary-contact health practitioners use in low-back pain.
START HERE: Which examination tests do you use to assess (in the first few consultations) a new acute low back pain (LBP) patient? They may have pain radiation into the sacroiliac/ buttock region but have no neurological or radicular symptoms and no serious pathology. Please tick the box which most closely reflects your practice: Physical impairment (A) Lumbar or lumbopelvic range of motion
100-61% Don’t know Very the test frequently
60-31% 30-1% Often Sometimes
0% Never
Often
Never
Flexion _______________________________________ Extension ____________________________________________ Lateral flexion (side-bending) _________________ Rotation ______________________________________ Do you measure any of the above ___________ with an instrument or other device?
(B) Orthopaedic & Neurological testing
Don’t know Very the test frequently
Sometimes
Combined patterns of movement _____________ McKenzie Side-shift Test__________________________ Repeated movement____________________ Visual postural analysis__________________ Leg length discrepancy __________________ Quadrant or Kemp’s Test_________________ Sacroiliac joint movement tests ____________ Sacroiliac joint pain provocation tests___________ Straight leg raise _______________________ Slump Test ____________________________ Dermatones, myotomes, reflexes etc _______ Other orthopaedic & neurological tests (indicate below) (Muscle tests and palpation are on the next page)
Fig. 1. Acute LBP assessment questionnaire.
2.2. Data analysis The percentages (and 95% CI) of responding clinicians who used each listed NSLBP assessment technique were calculated. To identify the proportion of clinicians who routinely use a particular assessment technique or who commonly use a technique for certain presentations, the proportions of clinicians reporting that they very frequently or often used a technique (31e100% of time) were calculated. To identify the proportion of
clinicians who use a particular assessment technique under any circumstances, the proportions of clinicians reporting that they ever used a technique (1e100% of time) were calculated. Proportions of those who nominated unlisted NSLBP assessment techniques were also calculated. As 57 unlisted symptoms and signs were nominated, but most were reported by few clinicians, we arbitrarily only report items nominated by more than one in 20 clinicians (>5%).
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P.M. Kent et al. / Manual Therapy 14 (2009) 88e100
(C) Muscle tests
Don’t know Very the test frequently
Often
Sometimes
Never
Often
Sometimes
Never
Muscle strength testing ___________________________ Applied Kinesiology___________________________ Biering-Sorensen Test ________________________ Muscle stabilising testing _____________________ Stabilising Pressure Biofeedback Test ________ Janda muscle imbalance testing ______________ Muscle length testing (name muscles) __________ Other muscle performance tests (indicate below)
(D) Palpation
Don’t know Very the test frequently
Muscle, fascia, skin and other soft tissue palpation __________________________ Bony landmark palpation for asymmetry ______ Joint palpation - passive movement testing ___ Palpation for tenderness______________________ Motion palpation (active or passive) __________ Craniosacral rhythm __________________________ Other palpatory tests (indicate below)
Pain
Don’t know Very the test frequently
Often
Sometimes
Never
Often
Sometimes
Never
Patient’s pain description _____________________ Pain drawings (including body chart) _________ Verbal pain scale _____________________________ Visual analogue pain scale ___________________ Numerical rating scale ________________________ Short Form McGill Pain Questionnaire _______ Other pain assessments (indicate below)
Disability
Don’t know Very test frequently
Oswestry Low Back Pain Questionnaire ______ Roland-Morris Disability Scale (RM-24 or RM-18) Quebec Back Pain Disability Scale ___________ Patient Specific Functional Scale _____________ Low-Back Outcome Score ____________________ Short Form 12 or 36 __________________________ Other disability assessments (indicate below)
Fig. 1 (continued).
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Behavioural assessment
Don’t know Very the test frequently
Often
Sometimes
Never
Often
Sometimes
Never
Waddell’s non-organic signs_____________________ Modified Core Network LBP questions_________ Fear-avoidance belief questionnaire____________ Distress & Risk Assessment Method:___________ (Modified somatic perception questionnaire & Zung depression scale) Other behavioural assessments (indicate below)
Imaging (whether in non-specific LBP these tests would inform your reasoning, not whether you personally would order them)
Don’t know Very the test frequently
Visual analysis of X-rays_________________ X-ray line drawing______________________ CT__________________________________ MRI_________________________________ Other imaging modalities (indicate below)
Please return your completed questionnaire in the envelope provided and the ‘return postcard’ separately. Fig. 1 (continued).
Frequency distributions were used to describe the use of assessment techniques across professions (very frequently, often, sometimes, and never/don’t know test). Bonferroni-adjusted ManneWhitney U tests were used to determine between-discipline differences in assessment technique use. Determination of the alpha level for each comparison was based upon the formula ‘alpha/number of comparisons’ where the number of comparisons ¼ (n(n 1))/2. In this study there were six groups (professional disciplines), resulting in 15 pairwise comparisons. Therefore, we reset the alpha level for 95% confidence in the results of any pair-wise comparison to 0.003 (0.05/15). To identify whether particular health domains (physical impairment, pain, activity limitation, psychosocial functioning, and imaging) were disproportionately assessed by clinicians, the proportions of responding clinicians who used any technique from each domain were calculated. Tests for significant differences in proportions across domains were conducted using Bonferroniadjusted inferential confidence intervals as described by Tryon (2001). In this comparison there were five domains, rendering 10 pair-wise comparisons, and this resulted in resetting the alpha level for 95% confidence in results of any pair-wise comparison to (0.05/ 10) ¼ 0.005. Results were graphed showing inferential confidence intervals that had been Bonferroni-adjusted. Presenting the data graphically in this way enables
a difference between proportions to be tested with 95% confidence by the observation of no visual overlap between any comparisons. To assist interpretive clarity without meaningful loss of precision, proportions and means were reported to the nearest percent. Statistical analysis was conducted using SPSS 10 (SPSS Inc., Chicago, IL) and Excel 2004 (Microsoft Corp., Redmond, WA).
3. Results Of 1200 questionnaires that were initially mailed, 9% were returned unopened, leaving a sample frame of 1093. We received 651 completed questionnaires (Physiotherapy n ¼ 113 (64% response), Manipulative Physiotherapy n ¼ 142 (78% response), Chiropractic n ¼ 111 (60% response), Osteopathy n ¼ 101 (57% response), General Medical Practice n ¼ 84 (42% response), Musculoskeletal Medicine n ¼ 100 (59% response), an overall response rate of 60%). Responder demographics are summarised in Table 1. For a more detailed description of responder demographics, see Kent and Keating (2004). 3.1. Current assessment of acute NSLBP The reported use by all survey respondents of each assessment technique is shown in Tables 2 and 3.
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P.M. Kent et al. / Manual Therapy 14 (2009) 88e100 Table 1 Survey respondent demographics Age (years)
Physiotherapy (n ¼ 113) Manipulative Physiotherapy (n ¼ 142) Chiropractic (n ¼ 111) Osteopathy (n ¼ 101) General Medical Practice (n ¼ 84) Musculoskeletal Medicine (n ¼ 100) Total (n ¼ 651)
Years since undergraduate graduation
LBP as a proportion of caseload
Median
Range
Median
Range
Median, %
Range, %
31e40 41e50 31e40 41e50 41e50 41e50 41e50
20e60þ 20e60þ 20e60þ 20e60þ 20e60þ 30e60þ 20e60þ
11e20 11e20 11e20 11e20 21e30 21e30 11e20
1e30þ 1e30þ 1e30þ 1e30þ 1e30þ 11e30þ 1e30þ
46e60 46e60 46e60 46e60 0e15 0e15 46e60
0e60þ 0e60þ 0e60þ 0e60þ 0e60 0e60þ 0e60þ
Many assessment techniques were used in usual care. Of the techniques that were used very frequently or often by more than half the clinicians, 81% (17 of 21 techniques) were assessments of physical impairments (Table 2). These were orthopaedic and neurological tests (visual postural analysis, straight leg raising, neurological testing, sacroiliac joint movement, and leg length), evaluation of lumbosacral range of movement (ROM) (flexion, lateral flexion, extension, and rotation), palpation findings (soft tissue palpation, tenderness palpation, passive joint movement, motion palpation, and bony landmark palpation), and muscle strength testing. Of the techniques that were used very frequently or often by more than half the clinicians, 14% (3 of 21) were assessments of pain (pain description, pain drawing, and verbal pain scale) (Table 2) and 5% (1 of 21) were the results of imaging (visual X-ray analysis) (Table 3). Evaluation of lumbosacral ROM was the most commonly reported assessment, but only 10% of clinicians measured ROM very frequently or often. Hence it appears that most clinicians use visual estimation of ROM. The most common form of pain assessment was the elicitation of a description of the pain, but more formal and validated techniques for measuring pain were used less frequently. The highest proportion of clinicians reporting the use (very frequently or often) of any listed method to assess activity limitation was 13%. Ten unlisted methods for assessing activity limitation were nominated by some clinicians but they were collectively used by less than 2% of all responding clinicians. Similarly, the highest proportion of clinicians reporting the use (very frequently or often) of any listed method to assess psychosocial functioning was 4%. Six unlisted methods for assessing activity limitation were nominated by some clinicians but they were also collectively used by less than 2% of all responding clinicians. Three additional unlisted assessment items were nominated by more than one in 20 clinicians. These were hip flexion/abduction/external rotation 5% (95%CI 3e6%), the results of bone scans 8% (95%CI 6e11%) and ultrasonography (muscle and visceral) 7% (95%CI 5e10%). The complete detail of the reported use of each of the 48
Gender (female), %
58.0 44.4 18.0 43.6 28.9 11.0 35.0
assessment techniques is contained in Appendix 1. An example of the data available for each technique is shown in Table 4. 3.2. Between-discipline similarities and differences When professional groups were compared, 44 of 48 of the reported assessment techniques (92%) had significantly different utilisation rates (Table 5). Some disciplines use particular techniques more than all other disciplines. To illustrate, Chiropractors assess quadrant/Kemps, ‘applied kinesiology’, X-ray visual analysis and X-ray line drawing more frequently than all other disciplines ( p < 0.000). Some disciplines use particular techniques less than all other disciplines. For example, GPs assess quadrant/Kemps, sacroiliac joint movement, sacroiliac pain, muscle length, pain drawings and magnetic resonance imaging (MRI) results less frequently than all other disciplines ( p < 0.001). For five techniques there was no variation across disciplines. All disciplines frequently assess pain description and all disciplines infrequently assess using Low Back Outcome Scores, the Short Form 12 and 36, and the Distress and Risk Assessment Method. Also, manual therapy disciplines (Physiotherapists, Manipulative Physiotherapists, Chiropractors and Osteopaths) use more assessment procedures than GPs and also use some techniques (combined movement, visual postural analysis, and passive joint testing) more frequently than Musculoskeletal Medicine Practitioners and GPs ( p < 0.002). 3.3. Assessment across health domains There were significant differences in the health domains within which respondents assess acute NSLBP, and these are shown in Fig. 2. Physical impairment, pain and imaging are commonly assessed, but activity limitation and psychosocial functioning are assessed less frequently. All (100%) of clinicians very frequently or often assess physical impairment, 99% (98e100%) very frequently or often assess pain, but only 21% (15e27%) very frequently or often assess activity
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Table 2 The assessment of physical impairment and pain in acute NSLBP Use of assessment techniques of physical impairment Proportion of survey respondents Often/very At any time who report using these frequently (1e100%) (31e100%) assessment techniques in acute NSLBP (95%CI) Lumbosacral ROM Flexion Lateral flexion Extension Rotation ROM measurement
97% 96% 94% 74% 10%
(95e99%) (94e98%) (92e96%) (70e78%) (7e13%)
99% 99% 99% 95% 30%
(98e100%) (98e100%) (98e100%) (93e97%) (26e34%)
Ortho and neuro testing Visual postural analysis Straight leg raise Neurological testing Sacroiliac joint movement Leg length Sacroiliac joint pain Slump Combined movement Quadrant/Kemps test Repeated movement McKenzie side-glide
86% 86% 62% 59% 57% 50% 50% 43% 37% 30% 17%
(83e89%) (83e89%) (57e67%) (54e64%) (52e62%) (45e55%) (45e55%) (38e48%) (32e42%) (26e34%) (13e21%)
90% 99% 95% 86% 93% 85% 79% 72% 68% 69% 44%
(87e93%) (98e100%) (93e97%) (83e89%) (91e95%) (82e88%) (75e83%) (68e76%) (63e73%) (64e74%) (39e49%)
Muscle tests Muscle strength testing Muscle length Muscle stabilisation Stabilising pressure biofeedback ‘Applied Kinesiology’ Janda tests BieringeSorensen test
57% 31% 30% 16% 12% 11% 2%
(52e62%) (26e36%) (26e34%) (12e20%) (9e15%) (8e14%) (1e3%)
96% 47% 49% 28% 28% 25% 9%
(94e98%) (42e52%) (44e54%) (24e32%) (24e32%) (21e29%) (6e12%)
Palpation Soft tissue palpation Tenderness palpation Passive joint movement Motion palpation Bony landmark palpation Craniosacral rhythm
96% 96% 89% 75% 88% 16%
(94e98%) (94e98%) (86e92%) (71e79%) (85e91%) (12e20%)
99% 99% 97% 90% 97% 31%
(98e100%) (98e100%) (95e99%) (87e93%) (95e99%) (26e36%)
(98e100%) (56e66%) (55e65%) (32e42%) (15e23%) (1e5%)
99% 81% 88% 68% 47% 14%
(98e100%) (77e85%) (85e91%) (63e73%) (42e52%) (11e17%)
Use of assessment techniques of pain Pain description 99% Pain drawing 61% Verbal pain scale 60% Numerical pain scale 37% Visual pain scale 19% McGill pain scale 3%
limitation, and 7% (3e11%) very frequently or often assess psychosocial function.
4. Discussion 4.1. Current assessment of acute NSLBP Diverse assessment methods for acute NSLBP were reported by primary care clinicians. This reflects a lack of consensus regarding best practice. Almost all were assessments of physical impairment and pain. There may
Table 3 The assessment of activity limitation, psychosocial functioning and the use of imaging results in acute NSLBP Use of assessment techniques of activity limitation Proportion of survey respondents Often/very who report using these frequently assessment techniques in acute (31e100%) NSLBP (95%CI) Patient-Specific Scale Oswestry Questionnaire RolandeMorris Scale LB Outcome Score Quebec Disability Scale Short Form 12 or 36
13% 6% 3% 2% 2% 1%
(10e16%) (4e8%) (1e5%) (1e3%) (1e3%) (0e2%)
At any time (1e100%)
23% 20% 10% 6% 7% 4%
(19e27%) (16e24%) (7e13%) (4e8%) (5e9%) (2e6%)
Use of assessment techniques of psychosocial function Waddell’s Non-organic Signs 4% (2e6%) 15% (12e18%) Fear-avoidance Questionnaire 1% (0e2%) 6% (4e8%) Distress and Risk 1% (0e2%) 4% (2e6%) Assessment Method Use of imaging results Visual X-ray analysis CT MRI X-ray line drawing
63% 33% 28% 17%
(58e68%) (28e38%) (24e32%) (13e21%)
97% 93% 83% 41%
(95e99%) (91e95%) (79e87%) (36e46%)
be a number of reasons for this. The results of other components of these survey data suggest that in providing care for NSLBP, many clinicians make patient management decisions based on putative subgroups (Kent and Keating, 2004) and that these subgroups are based on assessments of physical impairment and pain (Kent and Keating, 2005). Similarly, the subgrouping schemes published in the literature, and reported to be in common use, rely heavily on the assessment of physical impairment and pain (Battie´ et al., 1994; Foster et al., 1999; Gracey et al., 2002; McCarthy et al., 2004). Moreover, most manual therapy interventions attempt to reduce physical impairments and pain, and interventions in the manual therapy disciplines that explicitly focus on improving capacity for activity are rare. In addition, clinicians use physical impairment and pain as a means of monitoring progress, both within and between treatment sessions (Hahne et al., 2004). Clinicians most commonly nominate change in physical impairment and pain as treatment goals (Jette et al., 1994), and most LBP patients have an expectation that pain will improve within a treatment session (Grimmer et al., 1999). As changes in physical impairment and pain can be immediately apparent to clinicians and patients, observation of these changes engages both parties in the therapeutic encounter. Clinicians may perceive that change in other domains will not be as immediate and therefore be less important in decisions that arise within the therapeutic encounter. Although the assessment of ROM and of pain was almost universally performed, the formal measurement
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Table 4 Example of the complete data available for each of the 48 assessment techniques in Appendix 1 (The reported use of Visual X-ray analysis results in assessing acute NSLBPa)
Visual X-ray analysis Physiotherapy (n ¼ 113) Manipulative Physiotherapy (n ¼ 142) Discipline Chiropractic (n ¼ 111) Osteopathy (n ¼ 101) General Medical Practice (n ¼ 84) Musculoskeletal Medicine (n ¼ 100) Total (n ¼ 651)
Very frequently
Often
Sometimes
Never/Don’t know test
Non-response
25%b (n ¼ 27) 23% (n ¼ 32)
44% (n ¼ 48) 44% (n ¼ 60)
27% (n ¼ 31) 31% (n ¼ 43)
4% (n ¼ 4) 2% (n ¼ 3)
(n ¼ 3) (n ¼ 4)
46% 16% 16% 22% 25%
(n ¼ 50) (n ¼ 16) (n ¼ 13) (n ¼ 21) (n ¼ 159)
41% 39% 32% 21% 38%
(n ¼ 44) (n ¼ 39) (n ¼ 26) (n ¼ 20) (n ¼ 237)
12% 45% 43% 52% 34%
(n ¼ 13) (n ¼ 45) (n ¼ 36) (n ¼ 48) (n ¼ 216)
1% 0% 9% 5% 3%
(n ¼ 1) (n ¼ 0 (n ¼ 7) (n ¼ 5) (n ¼ 20)
(n ¼ 3) (n ¼ 2) (n ¼ 2) (n ¼ 6) (n ¼ 19)
Visual X-ray analysis informs NSLBP clinical decision-making in Chiropractors more frequently than in all other disciplines ( p < 0.003). a The question asked was whether these results would inform the clinician’s clinical decision-making in NSLBP, not whether the clinician would order the test. b Proportion of all responses to this question.
of these was less common. Clinicians may be unconvinced that the increased reliability and precision of formal measurement (Watkins et al., 1991; Youdas et al., 1991) justify the increased ‘burden of collection’. However, as third party justification and medicolegal expectations become more influential in primary care, increased measurement precision may become more common, regardless of the item being assessed. It would appear that clinical reasoning in acute NSLBP is commonly informed by the results of imaging. There is considerable evidence that the results of imaging are rarely contributory to NSLBP management (Deyo and Phillips, 1996; Bogduk, 2000a). However, although the survey instructions stated that this part of the questionnaire concerned conditions where there were no neurological or radicular symptoms and no serious pathology, it is possible that some clinicians who reported using imaging had the intention of using the results to strengthen the likelihood that the LBP was nonspecific.
the methods used to assess acute NSLBP and previous data show very poor consensus amongst clinicians regarding NSLBP subgroup composition (Kent and Keating, 2005). The question remains as to whether this is the unavoidable consequence of clinical uncertainty or whether greater standardisation is possible and potentially valuable in advancing health care. For example, if recent evidence of the utility of subgroupspecific treatment (Delitto et al., 1995; Flynn et al., 2002; Childs et al., 2004; Long et al., 2004; Brennan et al., 2006) continues to accumulate, greater standardisation of clinical assessment may follow. Alternatively, if evidence from multiple replication studies indicates that the effects of subgroup-specific treatment are not clinically important, greater standardisation using simple generic assessments of NSLBP may follow. While current evidence precludes the identification of best practice assessment, theoretically, greater standardisation would promote the accuracy of communication between stake holders in the management of LBP.
4.2. Between-discipline differences
4.3. Assessment across health domains
There were differences between professional disciplines in the use of particular assessments. This is likely to be due in part to within-discipline beliefs regarding the etiology of NSLBP, the utility of particular subgrouping schemes and the clinical importance of particular assessment items. It may also reflect differences in the information that clinicians require to inform patient-specific management decisions. Treatment decisions and the monitoring of change may require different information, depending on the therapeutic options used by different clinicians. Inadequate evidence is currently available to determine if the use of particular assessment techniques by any of the professional disciplines is more or less appropriate than their use by any other discipline. These data indicate significant between-discipline variation in
These survey data suggest that primary care clinicians typically assess pain and physical impairment in acute NSLBP patients, but infrequently assess activity limitation, and psychosocial functioning. It is possible that based on intuition and experience, some clinicians make ‘informal’ judgements regarding the psychosocial status of their patients. However, there is evidence that these judgements are likely to be less accurate than those based on data gathered using formal instruments (Spitzer et al., 1994; Haggman et al., 2004). There may be other reasons why clinicians currently do not routinely perform assessment of acute NSLBP across other health domains. Education and clinical culture have emphasised the assessment of physical impairment and pain. Assessment in other domains may
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Table 5 Summary of significant differences between professional disciplines in their use of assessments in NSALBP Technique
Significant between-discipline differences in the use of NSALBP assessments (pair-wise ManneWhitneyeU comparisons p < 0.003)
Extension
Physiotherapists, Manipulative Physiotherapists, GPs, and Musculoskeletal Medical Practitioners > Osteopaths Manipulative Physiotherapists > Chiropractors Manipulative Physiotherapists > Physiotherapists, Chiropractors or Osteopaths GPs > Chiropractors or Osteopaths Chiropractors > Physiotherapists or Manipulative Physiotherapists GPs > Physiotherapists or Manipulative Physiotherapists Musculoskeletal Medical Practitioners > Osteopaths Physiotherapists, Manipulative Physiotherapists, Chiropractors, and Osteopaths > GPs Physiotherapists, Manipulative Physiotherapists, Osteopaths, and Musculoskeletal Medical Practitioners > GPs Physiotherapists > Chiropractors, Osteopaths, or Musculoskeletal Medical Practitioners Manipulative Physiotherapists > Chiropractors, Osteopaths, or Musculoskeletal Medical Practitioners Physiotherapists, Manipulative Physiotherapists, and Osteopaths > GPs Physiotherapists > Chiropractors, Osteopaths, or Musculoskeletal Medical Practitioners Physiotherapists, Manipulative Physiotherapists, Chiropractors, and Osteopaths > GPs or Musculoskeletal Medical Practitioners Physiotherapists, Chiropractors, Osteopaths, and Musculoskeletal Medical Practitioners > Manipulative Physiotherapists or GPs Chiropractors and Osteopaths > Physiotherapists or Musculoskeletal Medical Practitioners Chiropractors > all other disciplines Physiotherapists, Manipulative Physiotherapists, Osteopaths, and Musculoskeletal Medical Practitioners > GPs Manipulative Physiotherapists > Physiotherapists All other disciplines > GPs Chiropractors, Osteopaths, and Musculoskeletal Medical Practitioners > Manipulative Physiotherapists Chiropractors and Osteopaths > Physiotherapists or Musculoskeletal Medical Practitioners All other disciplines > GPs Chiropractors and Musculoskeletal Medical Practitioners > Manipulative Physiotherapists Chiropractors > Physiotherapists or Osteopaths All other disciplines > Osteopaths Physiotherapists, Manipulative Physiotherapists, and Musculoskeletal Medical Practitioners > Chiropractors, Osteopaths, or GPs Chiropractors, GPs and Musculoskeletal Medical Practitioners > Physiotherapists or Manipulative Physiotherapists GPs > Osteopaths Chiropractors and Musculoskeletal Medical Practitioners > Manipulative Physiotherapists Chiropractors > Physiotherapists Chiropractors > all other disciplines Physiotherapists, Manipulative Physiotherapists, and Osteopaths > GPs Manipulative Physiotherapists > GPs Physiotherapists, Manipulative Physiotherapists, Chiropractors, and Osteopaths > GPs Physiotherapists, Manipulative Physiotherapists, and Chiropractors > Musculoskeletal Medical Practitioners Physiotherapists and Manipulative Physiotherapists > Chiropractors or Osteopaths Physiotherapists and Manipulative Physiotherapists > Chiropractors, Osteopaths, GPs, or Musculoskeletal Medical Practitioners Physiotherapists and Manipulative Physiotherapists > Chiropractors, Osteopaths, GPs, or Musculoskeletal Medical Practitioners Chiropractors, Osteopaths, and Musculoskeletal Medical Practitioners > GPs Physiotherapists and Manipulative Physiotherapists > Chiropractors, Osteopaths, GPs, or Musculoskeletal Medical Practitioners Chiropractors, Osteopaths, and Musculoskeletal Medical Practitioners > GPs Physiotherapists, Manipulative Physiotherapists, Chiropractors, and Osteopaths > GPs Physiotherapists, Chiropractors, and Osteopaths > Musculoskeletal Medical Practitioners Physiotherapists, Chiropractors, and Osteopaths > GPs or Musculoskeletal Medical Practitioners Chiropractors and Osteopaths > Manipulative Physiotherapists Physiotherapists, Manipulative Physiotherapists, Chiropractors, and Osteopaths > GPs or Musculoskeletal Medical Practitioners Manipulative Physiotherapists > Musculoskeletal Medical Practitioners
Lateral flexion Rotation ROM Combined movement McKenzie side-glide
Repeated movement Visual postural analysis Leg length discrepancy
Quadrant/Kemp’s Test
Sacroiliac joint movement
Sacroiliac joint pain
Straight leg raise Slump Neurological testing (Myotomes, dermatomes, reflexes, etc.) Muscle strength testing Applied Kinesiology BieringeSorensen Test Muscle stabilisation
Stabilising pressure biofeedback Janda
Muscle length
Soft tissue palpation Bony landmark palpation Passive joint movement Tenderness palpation
P.M. Kent et al. / Manual Therapy 14 (2009) 88e100
97
Table 5 (continued ) Technique
Significant between-discipline differences in the use of NSALBP assessments (pair-wise ManneWhitneyeU comparisons p < 0.003)
Motion palpation
Chiropractors and Osteopaths > Physiotherapists, Manipulative Physiotherapists, GPs, or Musculoskeletal Medical Practitioners Physiotherapists > GPs Osteopaths > all other disciplines Chiropractors > Physiotherapists, Manipulative Physiotherapists, GPs, or Musculoskeletal Medical Practitioners Physiotherapists > GPs No between-discipline differences Physiotherapists and Manipulative Physiotherapists > Chiropractors, Osteopaths, GPs, or Musculoskeletal Medical Practitioners Chiropractors, Osteopaths, and Musculoskeletal Medical Practitioners > GPs Physiotherapists > Chiropractors, GPs, or Musculoskeletal Medical Practitioners Manipulative Physiotherapists > GPs Musculoskeletal Medical Practitioners > Physiotherapists, Chiropractors, or Osteopaths Manipulative Physiotherapists > Osteopaths Physiotherapists and Manipulative Physiotherapists > GPs Physiotherapists > Chiropractors Physiotherapists, Manipulative Physiotherapists, and Musculoskeletal Medical Practitioners > Osteopaths Physiotherapists, Manipulative Physiotherapists, Chiropractors, and Musculoskeletal Medical Practitioners > GPs Physiotherapists, Manipulative Physiotherapists, and Chiropractors > Osteopaths Physiotherapists, Manipulative Physiotherapists, Chiropractors, and Musculoskeletal Medical Practitioners > Osteopaths Physiotherapists, Manipulative Physiotherapists, and Chiropractors > GPs Physiotherapists > Osteopaths and GPs Manipulative Physiotherapists > Chiropractors and Musculoskeletal Medical Practitioners No between-discipline differences No between-discipline differences Musculoskeletal Medical Practitioners > all other disciplines Physiotherapists and Manipulative Physiotherapists > Osteopaths No between-discipline differences Musculoskeletal Medical Practitioners > Osteopaths or GPs Manipulative Physiotherapists > Osteopaths No between-discipline differences Chiropractors > all other disciplines Chiropractors more frequently > all other disciplines Osteopaths > Manipulative Physiotherapists Physiotherapists > Chiropractors, Osteopaths, GPs, or Musculoskeletal Medical Practitioners Manipulative Physiotherapists > GPs or Musculoskeletal Medical Practitioners Physiotherapists > Chiropractors, Osteopaths, GPs, and Musculoskeletal Medical Practitioners Manipulative Physiotherapists, Chiropractors, Osteopaths, and Musculoskeletal Medical Practitioners > GPs Manipulative Physiotherapists > Chiropractors or Musculoskeletal Medical Practitioners
Craniosacral rhythm
Pain description Pain drawing
Verbal pain scales Visual pain scales Numerical pain scales McGill pain scale Oswestry Disability Questionnaire
RolandeMorris Disability Questionnaire Quebec Disability Questionnaire Patient-Specific Scale LB Outcome Score Short Form 12 or 36 Waddell’s Non-organic Signs Modified Core LBP Questions Fear-avoidance Questionnaire Distress & Risk Assessment Visual X-ray analysis X-ray line drawing CT MRI
be perceived as novel and/or clinicians may consider themselves inadequately trained to assess the effects of health conditions on other domains. For example, only recently in Australia have insurers actively promoted the reporting of activity limitation and participation outcomes (Australian Physiotherapy Association, 2003; Transport Accident Commission, 2003; Victorian WorkCover Authority, 2004). The movement towards more comprehensive patient assessment reflects a growing awareness of the role that a range of factors play in recovery from LBP. For instance, there is evidence that some psychosocial factors are associated with LBP outcome (Pincus et al., 2002).
It is possible that clinicians believe that levels of physical impairment and pain are strongly associated with performance in other domains such as activity limitation. Assessment of activity limitation and psychosocial function might therefore be perceived as providing information that does not warrant the time commitment required to collect and utilise these data. However, there is evidence that assessments in different domains measure different aspects of the patient’s presentation and that measurements in one domain are not good substitutes for measurements in another domain. Measurements taken at a single time consistently display a relatively weak linear relationship between domains (Deyo, 1986;
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Fig. 2. Assessment of acute NSLBP across health domains. The proportion of clinicians who assess NSLBP using any technique from these assessment domains. Note: the width of the 95% confidence intervals have been adjusted (Tryon, 2001) such that where no visual overlap occurs between confidence intervals for any particular comparison, a difference between these proportions can be observed with 95% confidence.
Onoyama-Ball, 1992; Waddell et al., 1992; Rainville et al., 1994; Johannsen et al., 1995; Lindstrom et al., 1995; Schonheinz, 1995; Gronblad et al., 1997; Riddle, 1997; Kuukkanen and Malkia, 2000; Sullivan et al., 2000; Mannion et al., 2001; Kovacs et al., 2004). It also may be that the focus of assessment in the first few consultations of acute NSLBP is on gathering information that informs immediate treatment decisions. Clinicians may believe that the favourable short term prognosis of most acute LBP pragmatically constrains the need to assess more than physical impairment and pain. While it is possible that other assessments used to monitor progress or determine outcome are obtained during later consultations, without baseline measurement such monitoring is likely to be under-informed. Routine assessment across domains may be advantageous, but clinicians may need to be convinced that it influences NSLBP management and improves patient outcomes. Currently, evidence of this is sparse. The recognition that aspects of activity limitation and psychosocial function are associated with NSLBP outcomes may not change clinician behaviour while clinicians remain uncertain regarding effective interventions signalled by these findings. This uncertainty may stem from inflexible beliefs and practices, limited relevant empirical research, limited knowledge of best practice or a lack of therapeutic resources.
The strengths of this survey design and results are: (1) these data form a historical record to benchmark acute NSLBP assessment practice, (2) data were gathered from a representative sample of primary care clinicians responsible for the treatment of NSLBP in Australia. The weaknesses of this survey design and results are: (1) a nonrespondent bias could not be determined for the 40% of clinicians who did not return completed questionnaires; (2) the data were based on clinician self-report, not observation of actual behaviour; and (3) caution may be required in generalising these results to other countries.
5. Conclusions Primary care clinicians report that they commonly assess symptoms and signs in acute NSLBP from the domains of physical impairment and pain. The assessment of symptoms and signs from the domains of activity limitation and psychosocial function was less common, although there is evidence that this information can be prognostically important and useful for outcome assessment. There were differences between professional disciplines in the use of particular assessments. Adoption of greater standardisation of assessment by clinicians
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may require demonstration of the capacity of this standardisation to improve patient outcomes. One pathway to promote standardisation would be further research to determine if the identification of subgroups of NSLBP based on clusters of symptoms and signs does result in better patient outcomes, or whether simple generic assessments provide adequate clinical information.
Competing interests The authors declare they have no competing interests.
Acknowledgements Elements of this work were supported by Faculty of Health Sciences (La Trobe University), Joint Coal Board Health & Safety Trust (Australia), Musculoskeletal Physiotherapy Association (Victoria). Peter Kent is supported by grant number 348366 from the National Health and Medical Research Council of Australia.
Appendix 1. Supplementary data Supplementary data associated with this article can be found, in the online version, at doi:10.1016/ j.math.2007.12.006.
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Available online at www.sciencedirect.com
Manual Therapy 14 (2009) 101e109 www.elsevier.com/math
Original article
Reduction of experimental muscle pain by passive physiological movements Michael Møller Nielsen a, Anne Mortensen a, Jakob Kierstein Sørensen a, Ole Simonsen b, Thomas Graven-Nielsen c,* a
College-of-Health, Aalborg, Department of Physiotherapy, Selma Lagerloefs Vej 2, 9220 Aalborg East, Denmark b Aalborg Hospital and Nordic Orthopaedic Division, Sdr. Skovvej 11, 2, 9000 Aalborg, Denmark c Center for Sensory-Motor Interaction (SMI), Laboratory for Experimental Pain Research, Aalborg University, Fredrik Bajers Vej 7D-3, DK-9220 Aalborg East, Denmark Received 22 September 2006; received in revised form 24 October 2007; accepted 2 December 2007
Abstract The analgesic effects of passive movements on deep-tissue pain have not been sufficiently explored in human studies. The purpose of this study was to examine the effect of passive physiological movements (PPMs) on deep-tissue pain sensitivity. Seventeen healthy subjects were included in this randomised crossover study. In one session an electrically driven bicycle performed 30 min PPM of the knee joint. Another session without PPM served as control. The effect of PPM on experimental muscle pain was assessed. Muscle pain was induced by i.m. injection of hypertonic saline into the tibialis anterior muscle and the pain intensity was scored on an electronic visual analogue scale (VAS). The pressure pain sensitivity was assessed by recording of pressure pain thresholds (PPTs). McGill Pain Questionnaire (MPQ) was used to describe the quality of the induced pain. Compared with the control session PPM demonstrated: (1) a reduction of the experimental muscle pain intensity (VAS area and peak) and duration (17e31%, P < 0.03), (2) lower MPQ score and a change in quality profile of experimental muscle pain (25%, P < 0.01) and (3) an increased PPT (17%, P < 0.0005). The present study demonstrated that PPM produced an immediate analgesic effect on deep-tissue pain indicating a possible involvement of neural inhibitory mechanisms. Ó 2008 Elsevier Ltd. All rights reserved. Keywords: Manual therapy; Joint mobilization; Passive physiological movements; Experimental muscle pain
1. Introduction Musculoskeletal physiotherapy is a keystone in the field of physiotherapy and its focus is mainly on identifying dysfunctional structures/mechanisms and attempting to correct any related subsequent biomechanical/ functional deficits (Shacklock, 1995; Maitland et al., 2002; Maitland, 2003). Basic assumptions and hypotheses in musculoskeletal physiotherapy are therefore often
* Corresponding author. Fax: þ45 98 15 40 08. E-mail address:
[email protected] (T. Graven-Nielsen). 1356-689X/$ - see front matter Ó 2008 Elsevier Ltd. All rights reserved. doi:10.1016/j.math.2007.12.008
based on clinical empirical knowledge with an attempt to rationalise these within existing biomedical theories (Rivett, 2004). Recently, manual physiotherapy has been criticised for not implementing an evidence-based approach in the examination and treatment of patients (Shacklock, 1995; Maitland et al., 2002; Zusman, 2002, 2004; Maitland, 2003; Rivett, 2004). In the last decade clinical and experimental studies in spinal manipulative therapy (SMT) have indicated possible neurophysiological effects for mobilization induced analgesia (Skyba et al., 2003; Souvlis et al., 2004; Sluka et al., 2006; Moss et al., 2007). Several studies have shown that both manipulation and mobilizations of
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the spine produce a hypoalgesic mechanism measured by pressure pain thresholds (PPTs), visual analogue scale (VAS) and neural provocation test (Hayek et al., 1995; Vicenzino et al., 1996, 1998a,b; Herzog et al., 1999; Dishman and Bulbulian, 2000; Sterling et al., 2001; Mohammadian et al., 2004; Devocht et al., 2005). Vicenzino and others investigated whether the hypoalgesia produced by SMT could be explained by opioid mediated descending inhibition. In general, an opioid antagonist (naxolone) did not influence the hypoalgesic response by SMT (Zusman et al., 1989; Souvlis and Wright, 1997; Paungmali et al., 2004). Other studies have shown involvement of the sympathetic nervous system with SMT with skin conductance, skin temperature, heart rate, respiratory rate and blood pressure as outcome parameters (Petersen et al., 1993; McGuiness et al., 1997; Vicenzino et al., 1998a; Knutson, 2001). Driven by these findings there has been a focus on SMT and potential involvement of the dorsal part of the periaqueductal grey matter (dPAG) in the mesencephalon. The PAG plays an important role for behavioural responses to pain, stress and other stimuli by coordinating responses of a number of systems including the nociceptive system, the autonomic nervous system (ANS) and motor system (Fanselow, 1991; Lovick, 1991; Morgan, 1991). Low threshold mechanoreceptors from joint and muscles project to the dPAG and therefore non-noxious afferent input as SMT might be an adequate stimulus to activate key regions of PAG and mediate a non-opioid analgesia (Yezierski, 1991; Shacklock, 1995; Simon et al., 1997; Vicenzino et al., 1998a,b, 2001; Sterling et al., 2001; McLean et al., 2002; Paungmali et al., 2003; Mohammadian et al., 2004; Mulligan, 2004; Zusman, 2004). To date, few studies have characterised the effects of peripheral joint mobilization techniques on pain responses. Skyba et al. (2003) showed that peripheral mobilization of hyperalgesic knee joints in rats increased the mechanical withdrawal threshold; i.e. an anti-hyperalgesic effect. The reduced sensitivity was intact after spinal blockade of opioid or GABAA receptors and potentially due to descending inhibitory mechanisms that utilize serotonin and noradrenalin via corticospinal projections from the PAG (Skyba et al., 2003). Sluka and Wright (2001) showed that mobilizing the rat knee joint for 9 min reversed mechanical hyperalgesia induced by intra-articular injection of capsaicin in the ankle joint (Sluka and Wright, 2001). Recently, a study using similar design showed that mobilization of the knee joint caused a bilateral increase in mechanical withdrawal threshold in conditions of acute muscle inflammation and chronic muscle and joint inflammation (Sluka et al., 2006). A human study on patients with osteoarthritis showed that 9 min of accessory joint mobilization of the knee joint was sufficient to induce an increased threshold for mechanical pressure both locally and
distant from the treated joint (Moss et al., 2007). Several studies have used Mulligan’s ‘‘Mobilizations with Movement’’ (MWM) for the treatment of patients with long-lasting lateral epicondylalgia and found an immediate sympathoexcitatory effect, a change in motor activity and pain relief (Simon et al., 1997; Vicenzino et al., 1998a,b, 2001; Paungmali et al., 2003; Mulligan, 2004). The aim of this study was to assess the efficacy of passive physiological movements (PPMs) on experimental muscle pain (saline-induced and pressure pain) in a randomised crossover study including healthy subjects. The hypothesis was that PPM of joints decreases pain sensitivity localised in the same neurological segment.
2. Material and methods 2.1. Subjects Seventeen healthy subjects (six males and 11 females) were recruited among physiotherapy students (mean age: 23.9 years, SD 2.5) by verbal and written announcement. The exclusion criteria were pain, a trauma or injury in the last month causing pain for more than 7 days, known degenerative conditions in the limbs, pelvis or spine, surgery in limbs, pelvis and spine, psychological and/or neurological diseases, pregnancy and known severe allergy. The criteria were ensured based on questionnaires, short interviews and palpation of the relevant muscles. All subjects received both verbal and written information before signing a consent form for participating. The study was approved by the local ethical review board (VN 2004/64) and was conducted in accordance with the Helsinki Declaration. 2.2. Experimental procedure This randomised crossover study included a control session and an intervention session separated by at least a 1-week interval. It was not possible to blind subjects or assessors to the specific intervention in each sessions but subjects were blinded to the hypothesis tested in the current study. The subjects were positioned in a supine position (Fig. 1). In the intervention session PPMs of the knee joint were performed for 30 min by an electrical bicycle. In the control session subjects lay relaxed on the plinth with their feet positioned in the bicycle (Fig. 1). The experimental assessments were similar in both sessions. Pressure pain thresholds (PPTs) were recorded before and 15, 25 and 35 min after start of PPM on both the left and right m. tibialis anterior (Fig. 2). The assessment site on m. tibialis anterior (muscle belly) was determined by palpation of the muscleetendon junctions and the midpoint in-between these was estimated and used for assessment. Fifteen minutes after the start of PPM
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avoid any therapeutic touch (Gagne and Toye, 1994; Gordon et al., 1998) and to ensure reproducibility of the technique performed. PPM in this study was set to 30 rpm and with a rotation movement equal to midrange of the knee joints physiological range. 2.4. Experimental muscle pain
Fig. 1. Illustrating the position of subjects during the experiment. During experimental muscle pain the subjects continuously regulated the VAS manually and the computer sampled data. PPMs were performed by an electrical bicycle at 30 rpm. The bicycle was stopped during assessment of PPTs.
(immediately after the PPT assessment) experimental muscle pain was induced in the right tibialis anterior by injection of hypertonic saline (2 cm distal to the site for PPT assessment). The injection was performed at the same time for all subjects and the experimental muscle pain intensity was scored continuously on an electronic VAS only interrupted by the recording of PPTs at 25 and 35 min after start of PPM. The PPM was started immediately after the injection. The bicycle was stopped (typically less than 3 min) when PPTs were assessed. 2.3. PPM The PPM was performed by an electrical bicycle (Reck Motomed Viva, RECK Technik, Germany) to
15 min. PPM/rest
Experimental muscle pain was induced by i.m. injection of 1 ml 5.8% sterile hypertonic saline into the tibialis anterior muscle. The muscle pain intensity was scored on a 10 cm electronic VAS where 0 cm indicated ‘‘No pain’’ and 10 cm ‘‘Maximum pain’’. The VAS scores were sampled every 2 s and recorded for 900 s. The maximum pain (VAS peak), the duration of pain and the area under the VAS-time curve (VAS area) were extracted. Upon resolution of pain the subject filled in a body chart marking all areas of pain. This was later digitized (ACECAD D9000þ, Taiwan) and the pain areas were estimated. Referred pain was defined as being pain isolated and distinct from the local pain caused by injection. Quality of the pain was assessed by completion of a Danish MPQ (Drewes et al., 1993). The MPQ data were analysed according to the total score of the 20 word groups. Words chosen by more than 30% of subjects were included in the statistics (Graven-Nielsen et al., 1997a). 2.5. PPTs PPT was measured in the middle of the belly of the m. tibialis anterior, according to palpated landmarks (Kendall et al., 1993), with a handheld pressure algometer equipped with a 1 cm2 probe (Somedic Produktion AB, type 2, Sollentuna, Sweden). Pressure was applied with approximately 50 kPa/s in a simple, continuous ascending series. The subject was instructed to press a button at the moment the pressure stimulation elicited ‘‘just noticeable’’ pain. The mean of three measurements defined the PPT. Pressure algometry was performed by
10 min. PPM/rest
10 min. PPM/rest
VAS scale in use
Baseline PPT
PPT 1 and injection of hypertonic saline
VAS scale in use
PPT 2
PPT 3
Fig. 2. Schematic illustration of the experimental protocol. PPTs were recorded at baseline, just before injection of hypertonic saline (PPT1), 15 min after injection (PPT2), and at the end of the study (PPT3, 10 min after PPT2). PPMs are only performed in the intervention session. In the control session the subjects rest in a supine position. VAS was continuously recorded after the injection and only interrupted by PPT measurements.
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the same investigator throughout the experiment and prior to the study intensive training sessions were performed to increase accuracy (Fischer, 1987; Ohrbach and Gale, 1989; Vanderweeen et al., 1996; Smidt et al., 2002; Ylinen et al., 2007). During and post-intervention recordings were normalized to baseline recordings (100%). 2.6. Statistics Data are presented as mean values and standard deviation (SD). VAS, MPQ and pain area data were analysed by two-way mixed-model ANOVA with factors ‘condition’ (repeated: control and PPM) and ‘sequence’ (between group: PPM at first session or PPM at second session). PPT data were analysed by a four-way mixedmodel ANOVA with factors ‘condition’ (repeated: control and PPM), ‘side’ (repeated: left and right), ‘time’ (repeated: baseline, 15, 25 and 35 min) and ‘sequence’ (between group: PPM at first session or PPM at second session). When the ANOVA was found significant the NewmaneKeuls (NK) test was used for post-hoc analysis and to correct for multiple comparisons. The limit for significance was defined as P < 0.05.
3. Results 3.1. Experimental muscle pain The VAS scores were lower during PPM than during the control session (Fig. 3). The VAS-time curve identified two maxima: the first appearing immediately after the injection and the second maximum appears
during the final assessment of PPT. In the intervention session VAS peak was significantly lower, the VAS area (0e600 s) was significantly smaller and the duration of pain was significantly shorter during PPM than during the control session (Table 1; ANOVA: df ¼ 1; F > 4.64; P < 0.048). The area and distribution of pain were not significantly decreased in the PPM session (Fig. 4, Table 1). The MPQ data were significantly lower in the PPM session than in the control session (Table 1). In both sessions at least 30% of the subjects described the pain as ‘‘drilling, tingling, taut and tight’’. In the control session 47% used the word ‘‘miserable’’ whereas in the PPM session 41% chose the word ‘‘annoying’’ (lowest score) in the same word category. 3.2. Pressure algometry In one subject, PPTs were not reached before the maximum pressure limit (2000 kPa) and data were incomplete for two subjects. As a consequence 14 subjects were included for further analysis. The ANOVA showed an effect of condition (ANOVA: df ¼ 1; F ¼ 24.2; P ¼ 0.0004) which, however, was dependent on an interaction between the condition and time factors: left and right side PPTs during (15 and 25 min) and after (35 min) the PPM intervention increased significantly compared with baseline recordings and similar time points in the control session (Fig. 5; ANOVA: df ¼ 3; F ¼ 8.16; P ¼ 0.0003; NK: P < 0.001). The PPTs were 20 23% higher in the PPM study compared with baseline and 17 18% higher when compared with the control session (Fig. 5).
4. Discussion 5
4
VAS (cm)
The present study showed that the pain induced by intramuscular injection of hypertonic saline in m. tibialis anterior was reported lower with PPM of the knee joint. Moreover, in the intervention session some subjects experienced a characteristic change in pain quality expressed by the weaker word ‘‘annoying’’ in comparison to the stronger word ‘‘miserable’’ used in the control study. Throughout the intervention study PPT was increased compared with the baseline level and the control
Control PPM
3
2
1
Table 1 Mean (SD) VAS parameters after saline-induced muscle pain
0 0
5
10
15
20
25
Time (min) Fig. 3. The mean VAS-time curve after injection of hypertonic saline into the tibialis anterior muscle in the control (light grey) and PPM (solid) sessions. The injection was performed after 15 min with PPM. The VAS scores in the PPM session are clearly reduced compared with the control session.
VAS area0e600 (cm s) VAS area600e900 (cm s) VAS peak (cm) VAS duration (s) Pain area (A.U.) MPQ score
PPM
Control
P-value
1344.3 858.5 112.2 206.7 4.40 2.57 815.6 279.8 2.43 1.95 3.12 1.07
1950.4 1091.7 400.6 629.5 5.28 2.42 1016.1 299.2 2.97 2.23 4.15 1.97
0.03 NS 0.02 0.02 NS 0.01
NS: not significant; A.U.: arbitrary units.
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Fig. 4. The pain distribution (ventral and dorsal view) after injection of hypertonic saline into the right tibialis anterior muscle in the control and PPM sessions.
session. These data therefore indicate that PPM results in hypoalgesia of deep tissue.
4.1. Experimental muscle pain The intramuscular injection with hypertonic saline caused a moderate to high muscle pain intensity associated with referred pain, and a quality of pain described as ‘‘drilling, tingling, taut and tight’’ which is similar to observations previously reported (Graven-Nielsen et al., 1997a,b, 1998, 2003; Gibson et al., 2006). The intensity and duration of experimental pain in the PPM session were on average scored approximately 1 cm lower and 200 s less compared with the control session. This might be explained by an inhibitory mechanism caused by PPM.
Similar findings have been shown in animal studies where joint mobilization reduced secondary hyperalgesia due to intra-articular injection of capsaicin; mobilization of the knee joint for more than 9 min diminished the withdrawal threshold to mechanical stimuli and the analgesia lasted for at least 30 min (Sluka and Wright, 2001; Skyba et al., 2003). Moreover, mobilization of the knee joint caused bilateral increases in mechanical withdrawal threshold in conditions of acute and chronic muscle inflammation, and chronic joint inflammation (Sluka et al., 2006). A similar study on patients with osteoarthritis reported that 9 min mobilization of the knee joint provided a significant local and widespread hypoalgesia when measured by PPT (Moss et al., 2007). Recently, however, a MWM intervention in healthy controls with experimentally induced lateral epicondylalgia did not reduce pain intensity (Slater et al., 2006).
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PPT (% of baseline)
Control PPM
∗
125
∗
∗
100
75
50 Baseline
10
20
30
40
Time (min) Fig. 5. Mean PPT (SD, N ¼ 14) as a percentage of baseline at baseline and during 35 min with PPMs. Hypertonic saline is injected after the assessment at 15 min. *Significantly different from baseline and control recordings at same time point (NK: P < 0.0005).
These contradictory results may be due to the use of a sustained mobilization procedure as opposed to rhythmical mobilizations as described previously (Mulligan, 2004; Moss et al., 2007). Treatment technique and duration might also be of importance for the reported differences. Other studies have advocated that repetitive movement rather than sustained pressure for a critical amount of time is a key factor in initiation of mechanisms related to the hypoalgesia (Sluka and Wright, 2001; Moss et al., 2007). In the present study only a tendency for reduced local and referred pain areas were found although the pain intensity was significantly decreased. The diffuse characteristics of muscle pain combined with the complex mechanisms involved in referred pain is likely to reduce the sensitivity of pain area assessment and therefore explain the present non-significant effects on pain distribution (Graven-Nielsen, 2006). Furthermore memory bias could account for a possible inaccuracy in reporting the pain area (Edwards et al., 1995; Kikuchi et al., 2006). 4.2. Deep-tissue pressure pain sensitivity The present results demonstrate that 15 min of PPM evoked a significant increase in bilateral PPTs compared with baseline levels and the control session. The increased PPT was consistently found throughout the PPM experiment. In the control session the PPT assessments were not significantly increased compared with baseline. It should be noted that the assessor was not blinded to the experimental intervention and therefore the PPT results could be biased (Ohrbach et al., 1998).
However, the saline-induced muscle pain shows the same hypoalgesic effects of PPM as pressure algometry (see above). The saline-induced muscle pain method has no direct assessor influence indicating that the confounding effect of the non-blinded assessor for pressure algometry is limited. The fourth and final PPT assessment in the control condition was not significantly decreased compared with baseline assessment although it approached significance. In case this reaches significance the decrease might be explained by peripheral sensitisation due to repeated pressure assessments (Lauersen et al., 1997a,b; Kosek and Hansson, 2002). Interestingly, the saline-induced pain did not induce muscle hyperalgesia as also reported previously in numerous studies (Graven-Nielsen, 2006) suggesting that the inhibitory mechanism is not dependent on conditions of hyperalgesia. Recent studies have reported that manual therapy of painful joints causes a significant increase in the levels of PPT measurements in line with these experimental findings (Vernon et al., 1990; Vicenzino et al., 1998a,b, 2001; Sterling et al., 2001; Paungmali et al., 2003). 4.3. Potential mechanisms of joint mobilization analgesia Previous studies have suggested that the dPAG in the mesencephalon is important for the analgesic effects of manual therapy due to activation of the sympathetic nervous system as seen in a number of studies (McGuiness et al., 1997; Simon et al., 1997; Sterling et al., 2001; Paungmali et al., 2003; Skyba et al., 2003; Souvlis et al., 2004; Moulson and Watson, 2006). It is proposed that descending pathways from dPAG influence the activity of inhibitory interneurons at the spinal level and thereby induce analgesia specific to mechanical stimulations (Shacklock, 1995; Vicenzino et al., 1998a,b, 2001; Sterling et al., 2001; Skyba et al., 2003). Skyba et al. (2003) reported that mobilization of rat knee joints did not induce hypoalgesia due to spinal opioids or segmental mechanisms due to release of GABAA, but more likely due to descending inhibitory mechanisms that utilize serotonin and noradrenalin via corticospinal projections from dPAG. Low threshold mechanoreceptors from joint and muscle have been shown to project to the PAG and a non-noxious afferent input (e.g. SMT), might be an adequate stimulus to activate the key regions of the PAG (Yezierski, 1991; Shacklock, 1995; Vicenzino et al., 1998a,b, 2001; Sterling et al., 2001; McLean et al., 2002; Paungmali et al., 2003; Mohammadian et al., 2004; Souvlis et al., 2004; Zusman, 2004). In the present study a reduction of sensitivity for mechanical stimuli (increase in PPT) was found. This could probably be related to the continuous performance of PPM stimulating Ab mechanoreceptors bilaterally and thereby activating key regions of PAG (and other
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midbrain nuclei) to induce a hypoalgesic mechanism (Pickar, 2002; Souvlis et al., 2004). Interestingly, bilateral and extra-segmental hypoalgesia to pressure have also been found during voluntary submaximal isometric muscle contraction, suggesting a generalized inhibitory mechanism initiated by muscle afferent fibre activity or by increased release of blood b-endorphins due to muscle contraction (Kosek and Lundberg, 2003).
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Acknowledgments We would like to thank Hanne Lisby, Physiotherapist, Master of Ethics and Values in Organisations, ‘‘Collegeof-Health, Aalborg’’, Department of Physiotherapy, for her kind support and advice during the development of this study.
4.4. Study limitations References In the present study the muscle activity was not monitored but a previous study report only sporadic muscle activity at a very low level during passive bicycling (Christensen et al., 2000). Therefore it is unlikely that the hypoalgesic mechanisms are due to muscle activity. Furthermore, blood flow/circulation was not monitored during the experiment and therefore a hypothetical risk of wash out of the i.m. hypertonic saline during PPM is present. In the present study only minimal plantar/dorsal movement occurred at the ankle joint which is the m. tibialis anterior primary function and it is not likely to account for the decreased saline-induced muscle pain during PPM. Another possible confounding factor that pertains to all experimental pain research is a shift of attention during pain. In the present study the laboratory was organized so that a minimum of disturbing elements and communication were interfering. 4.5. Perspectives Previous studies propose a link between range of motion and duration of treatment and the analgesic effect (Katawich, 1999; Sluka and Wright, 2001; Moss et al., 2007). Thus, it is possible that an intervention with PPM close to maximum range of motion could produce an adequate hypoalgesic mechanism within a shorter timeframe. The specific pain reduction of approximately 1 cm on a VAS is clinically relevant as indicated by the Cochrane Library where 1 cm pain reduction is identified as being clinically relevant (Gross et al., 2002). Therefore it is reasonable to assume that PPM can be used as a method for analgesia in clinical settings.
5. Conclusion The present study showed that PPM performed at the knee joint had a significant analgesic effect on deeptissue pain sensitivity in line with the hypothesis of the current study. Further studies are needed to clarify the exact neurophysiological mechanisms involved in this type of manual treatment and its analgesic effects.
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Mulligan B. Manual therapy ‘‘NAGS’’, ‘‘SNAGS’’, ‘‘MWM’’ etc. 5th ed. New Zealand: Plane View Services; 2004 [chapter 1]. Ohrbach R, Gale EN. Pressure pain thresholds, clinical assessment and differential diagnosis: reliability and validity in patients with myogenic pain. Pain 1989;39:157e69. Ohrbach R, Crow H, Kamer A. Examiner expectancy effects in the measurements of pressure pain thresholds. Pain February 1998; 74(2e3):163e70. Paungmali A, Vicenzino B, Smith M. Hypoalgesia induced by elbow manipulation in lateral epicondylalgia does not exhibit tolerance. Physical Therapy 2003;4:448e54. Paungmali A, O’Leary S, Souvlis T, Vicenzino B. Naxolone fails to antagonize initial hypoalgesic effect of a manual therapy treatment for lateral epicondylia. Journal of Manipulative and Physiological Therapeutics 2004;23(3):180e5. Petersen NP, Vicenzino B, Wright A. The effects of a cervical mobilisation technique on sympathetic outflow to the upper limb in normal subjects. Physiotherapy Theory and Practice 1993;9: 146e9. Pickar JG. Neurophysiological effects of spinal manipulation. The Spine Journal 2002;2:357e71. Rivett J. Clinical reasoning for manual therapists. 1st ed. London: Butterworth & Heinemann; 2004 [chapter 1e2]. Shacklock M. Moving in on pain: Conference proceedings. 2. Printing. 1st ed. Australia: Butterworth & Heinemann; 1995 [chapter 1e3]. Simon R, Vicenzino B, Wright A. The influence of an anteroposterior accessory glide of the glenohumeral joint on measures of peripheral sympathetic nervous system function in the upper limb. Manual Therapy 1997;2(1):18e23. Smidt N, Van Der Windt DA, Assendelft WJ, Mourits AJ, Deville WL. Interobserver reproducibility of the assessment of severity of complaints, grip strength, and pressure pain threshold in patients with lateral epicondylitis. Archives of Physical Medicine and Rehabilitation 2002;83(8):1145e50. Skyba DA, Radhakrishnan R, Rohlwing JJ, Wright A, Sluka KA. Joint manipulation reduces hyperalgesia by activation of monoamine receptors but not opioid or GABA receptors in the spinal cord. Pain 2003;106:159e68. Slater H, Arendt-Nielsen L, Wright A, Graven-Nielsen T. Effects of manual therapy technique in experimental lateral epicondylia. Manual Therapy 2006;11:107e17. Sluka KA, Skyba DA, Radhakrishnan R, Leeper BJ, Wright A. Joint mobilization reduces hyperalgesia associated with chronic muscle and joint inflammation in rats. The Journal of Pain 2006;7(8): 602e7. Sluka KA, Wright A. Knee joint mobilisation reduces secondary mechanical hyperalgesia induced by capsaicin injection into the ankle joint. European Journal of Pain 2001;5:81e7. Souvlis T, Vicenzino B, Wright A. Neurophysiological effects of spinal manual therapy. In: Boyling JD, Jull GA, editors. Grieve’s modern manual therapy. 3rd ed. UK: Churchill Livingstone; 2004. p. 367e79. Souvlis T, Wright A. The tolerance effect: its relevance to analgesia produced by physiotherapy interventions. Physical Therapy Reviews 1997;2:227e37. Sterling M, Jull G, Wright A. Cervical mobilisation: concurrent effects on pain, sympathetic nervous system activity and motor activity. Harcourt Publishers Ltd. Manual Therapy 2001;6(2):72e81. Vanderweeen L, Oostendorp RA, Vaes P, Duquet W. Pressure algometry in manual therapy. Manual Therapy 1996;1(5):258e65. Vernon HT, Aker P, Burns S, Viljakaanen S, Short L. Pressure pain threshold evaluation of the effect of spinal manipulation in the treatment of chronic neck pain: a pilot study. Journal of Manipulative and Physiological Therapeutics 1990;13(1):13e6. Vicenzino B, Collins D, Wright A. The initial effects of a cervical spine manipulative treatment on the pain and dysfunction of lateral epicondylalgia. Pain 1996;68:69e74.
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Technical and measurement report
Head repositioning accuracy to neutral: A comparative study of error calculation Robert Hill, Pa˚l Jensen, Tor Baardsen, Kristian Kulvik, Gwendolen Jull, Julia Treleaven* Division of Physiotherapy, The School of Health and Rehabilitation Sciences, The University of Queensland, Brisbane 4072, Queensland, Australia Received 28 February 2007; received in revised form 6 February 2008; accepted 28 February 2008
Abstract Deficits in cervical proprioception have been identified in subjects with neck pain through the measure of head repositioning accuracy (HRA). Nevertheless there appears to be no general consensus regarding the construct of measurement of error used for calculating HRA. This study investigated four different mathematical methods of measurement of error to determine if there were any differences in their ability to discriminate between a control group and subjects with a whiplash associated disorder. The four methods for measuring cervical joint position error were calculated using a previous data set consisting of 50 subjects with whiplash complaining of dizziness (WAD D), 50 subjects with whiplash not complaining of dizziness (WAD ND) and 50 control subjects. The results indicated that no one measure of HRA uniquely detected or defined the differences between the whiplash and control groups. Constant error (CE) was significantly different between the whiplash and control groups from extension ( p < 0.05). Absolute errors (AEs) and root mean square errors (RMSEs) demonstrated differences between the two WAD groups in rotation trials ( p < 0.05). No differences were seen with variable error (VE). The results suggest that a combination of AE (or RMSE) and CE are probably the most suitable measures for analysis of HRA. Ó 2008 Elsevier Ltd. All rights reserved. Keywords: Joint position error; Measurements; Whiplash; Neck pain; Head repositioning accuracy
1. Introduction Patients with neck pain of both traumatic and insidious onset have deficits in cervical joint position error or head repositioning accuracy (HRA) (Revel et al., 1991; Heikkila¨ and A˚stro¨m, 1996; Loudon et al., 1997; Kristjansson et al., 2003; Treleaven et al., 2003). HRA to neutral (Revel et al., 1991) is most commonly used as it has been the most reliable test for determining differences between neck pain and control subjects (Kristjansson et al., 2003). Nevertheless whilst disturbances in HRA to neutral have been
* Corresponding author. E-mail address:
[email protected] (J. Treleaven). 1356-689X/$ - see front matter Ó 2008 Elsevier Ltd. All rights reserved. doi:10.1016/j.math.2008.02.008
consistently reported in whiplash cohorts (Heikkila¨ and Wenngren, 1998; Treleaven et al., 2003), results are less uniform in patients with neck pain of insidious onset (Rix and Bagust, 2001; Lee et al., 2005). Comparison between studies to understand these differences is difficult because of different measurement instruments, methodologies and properties of error used. The interest in this study was properties of error. Previous studies have used absolute error (AE) (Heikkila¨ and A˚stro¨m, 1996; Loudon et al., 1997; Kristjansson et al., 2003; Treleaven et al., 2003), constant error (CE) (Revel et al., 1991; Michaelson, 2004; Lee et al., 2006), variable error (VE) (Michaelson, 2004; Lee et al., 2006; Strimpakos et al., 2006) and/or root mean square error (RMSE) (Lee et al., 2006). The AE
R. Hill et al. / Manual Therapy 14 (2009) 110e114
describes the average AE (Schmidt and Lee, 1999). CE includes both the under and overestimations of the target position and represents the average magnitude and direction of the errors (Schmidt and Lee, 1999). The VE measures the variability in the results and is thought to reflect the effect of noise in the sensorimotor system (Clark et al., 1995). RMSE represents an overall measure of how successful the subject was in achieving the target (Schmidt and Lee, 1999). Recently it has been proposed that the CE and/or VE may be more suitable than AE to assess HRA (Michaelson, 2004). Studies comparing individuals with and without lumbar or thoracic pain have used more than one measurement of error (Brumagne et al., 2000; Koumantakis et al., 2002). While arguments might be mounted for the use of each particular error measurement, no study has compared these different calculations of HRA to neutral to determine whether one or more methods are better able to discriminate between control and neck pain subjects. This study compared the four measures of error between a control group and subjects with whiplash both complaining and not complaining of dizziness. 2. Methods
111
extensions. The 3-Space Fastrak system (Polhemus, Navigation Science Division, Kaiser Aerospace, Vermont) measured the positions of two sensors (one at the forehead and one at C7) relative to a source and the difference between the starting (zero) and position on return was calculated in degrees. The error in the primary plane of movement was used as the measure for HRA as directed by our previous research (Treleaven et al., 2003). 2.3. Procedure The starting position for the HRA tests was in sitting with the head in the neutral resting position. Subjects were blindfolded and were asked to perform the test neck movement within comfortable limits returning as accurately as possible to the starting position. Subjects indicated verbally when they had returned and this was marked electronically. The examiner, guided by realtime display, manually repositioned the subject’s head back to the original starting position before each trial. Three trials (as directed by our previous research) were performed for each movement (Treleaven et al., 2003). The subjects were able to visually re-centre their starting position prior to each new movement direction (Treleaven et al., 2003, 2006).
2.1. Subjects 2.4. Data management and statistical analysis The data set from a previous study (Treleaven et al., 2006) was used and consisted of 100 whiplash subjects with persistent pain, at least 3 months post-injury. Fifty subjects reported symptoms of dizziness or unsteadiness at least once per week (subjects with whiplash complaining of dizziness e WAD D) and 50 did not (subjects with whiplash not complaining of dizziness e WAD ND). Data from 50 control subjects (40 reported in Treleaven et al., 2006 and 10 additional subjects) were also used. The whiplash groups were comparable with respect to age (WAD D mean 35.5 SD (8.1) years, WAD ND group mean 35.0 SD (9.5) years) and mean time since injury (WAD D 1.4 range 0.35e3 years, WAD ND 1.6 range 0.3e3 years). The control subjects had no history of whiplash, neck pain, headache or dizziness. The mean age was 29.5 SD (8.3) years. Approval for the study was gained from the Institutional Medical Ethics Committee. All participants provided their informed consent. 2.2. Instrumentation and measurements As described previously (Treleaven et al., 2006) the subject’s HRA to the natural head posture was tested following active cervical left and right rotations and
VE ¼
The four different methods of presenting HRA for each movement direction were calculated as follows: AE: the mean of the total deviation from the starting point over the three trials, ignoring positive (overshoot) and negative (undershoot) values, i.e. (Treleaven et al., 2003): AE ¼ ðabsolute of raw error trial 1Þ þ ðabsolute of raw error trial 2Þ þ ðabsolute of raw error trial 3Þ=3: CE: the mean of the raw error over the three trials incorporating the positive and negative values in each trial, i.e. (Lee et al., 2006): CE ¼ ðraw error trial 1Þ þ ðraw error trial 2Þ þ ðraw error trial 3Þ=3: VE: the square root of the mean of the difference between the raw error and the calculated CE (as above) squared, i.e. (Lee et al., 2006):
rffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi ffi ðraw error trial 1 CEÞ2 þ ðraw error trial 2 CEÞ2 þ ðraw error trial 3 CEÞ2 =3:
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RMSE: the square root of the sum of the CE squared and the VE squared, i.e. (Lee et al., 2006): RMSE ¼
qffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi 2 CE þ VE2 :
(Table 1, Fig. 3). Against the trend of other results, in CE the WAD ND group was significantly more accurate than controls (Fig. 3).
4. Discussion The data from each movement were analysed for between group differences with a generalized linear multivariate model, using SPSS statistical software. A preliminary analysis showed a significant age difference between the control group and the whiplash groups thus age was included as a co-variate to ensure that this could not account for any differences seen between the groups.
3. Results 3.1. Extension CE demonstrated significantly greater means between both the WAD D and controls and between the WAD ND and controls (Table 1, Fig. 1). There were no differences in CE between WAD D and WAD ND and no between group differences in any of the other measures. 3.2. Left rotation CE demonstrated significant differences between WAD D and controls and WAD D and WAD ND (Table 1, Fig. 2). Differences in AE and RMSE were also seen between the controls and WAD D. 3.3. Right rotation Both AE and RMSE distinguished between both the whiplash groups and between the WAD D and controls
The results of this study indicated that no one measure of HRA uniquely detected or defined the differences between the whiplash and control groups. The results suggest that a combination of AE and CE are probably the most suitable measures for analysis of HRA when assessing patients with whiplash. The RMSE mirrored exactly the AE findings and thus the use of both measures may be superfluous. The value of the measure of VE in the test of return to the natural head posture will be discussed. An argument can be mounted in support of the use of both AE and CE in future studies of HRA in patients with neck disorders. The AE indicates the accuracy of the deviation from neutral and demonstrated that the WAD D were, on average, further from the neutral target than healthy control subjects from rotation which is in accordance with other studies (Heikkila¨ and Wenngren, 1998; Treleaven et al., 2003). However, AE did not detect these differences in return from extension. The CE is a measure of the direction and deviation of the end position. It has benefits over AE and RMSE, which do not consider direction (Schmidt and Lee, 1999). Heikkila¨ and A˚stro¨m (1996) and Treleaven et al. (2003) counted overshoots and undershoots rather than calculating the CE, and showed subjects with whiplash overestimated whilst control subjects under estimated neutral. Similar results were reflected in this current analysis. The CE detected differences between controls and both whiplash groups in return from extension and also detected the overshooting of WAD D
Table 1 The differences in joint position error (degrees) between groups in the primary planes of movement for each measure and the p values for between group analysis Movement
Measure
Control
WAD ND
Ext
CE VE AE RMSE
Mean (SE) 0.35 1.36 3.01 3.41
(0.5) (0.2) (0.3) (0.3)
Mean (SE) 1.09 1.58 2.84 3.14
(0.5) (0.1) (0.3) (0.3)
Rot (L)
CE VE AE RMSE
0.74 1.59 2.47 2.72
(0.5) (0.2) (0.4) (0.4)
0.70 1.57 3.07 3.40
(0.5) (0.2) (0.3) (0.3)
Rot (R)
CE VE AE RMSE
2.11 1.47 3.16 3.42
(0.6) (0.2) (0.4) (0.4)
0.43 1.65 2.93 3.24
(0.5) (0.2) (0.4) (0.4)
WAD D
WAD D vs C
ND vs D
C vs ND
Mean (SE)
p Value
p Value
p Value
1.24 1.61 3.61 3.94
(0.5) (0.1) (0.3) (0.3)
0.02* 0.28 0.17 0.23
0.82 0.89 0.06 0.06
0.04* 0.34 0.69 0.55
1.19 1.88 4.01 4.36
(0.5) (0.2) (0.3) (0.3)
0.01* 0.28 0.00* 0.00*
0.01* 0.20 0.05 0.05
0.96 0.90 0.24 0.19
1.83 1.99 4.55 4.87
(0.6) (0.2) (0.4) (0.4)
0.73 0.06 0.02* 0.02*
0.07 0.21 0.00* 0.00*
0.04* 0.51 0.69 0.76
WAD D ¼ subjects with whiplash complaining of dizziness, WAD ND ¼ subjects with whiplash not complaining of dizziness, CE ¼ constant error, AE ¼ absolute error, RMSE ¼ root mean square error, and VE ¼ variable error.
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R. Hill et al. / Manual Therapy 14 (2009) 110e114 6
5 4
*
*
Control WAD ND
5
Control
*
*
*
* *
WAD D
WAD D
3
WAD ND
Degrees
Degrees
4 2 1 0 -1
Contant error
Variable error
Absolute error
Root mean square error
3
2
1
-2
Fig. 1. The results of the various measures of JPE from extension means and standard error for each group (*p < 0.05). WAD D ¼ subjects with whiplash complaining of dizziness and WAD ND ¼ subjects with whiplash not complaining of dizziness.
compared to the undershooting of the other groups in return from left rotation. The inability of AE and RMSE to detect such differences between the control (undershot) and WAD subjects (overshot) in return from extension is highlighted by the non-significance of these errors in extension trials. Nevertheless, the AE detects differences that CE will not when the scores are a scatter of positives (overshoot) and negatives (undershoot). The VE revealed no between group differences in measures from any movement directions indicating that all subjects were equally consistent between the three trials for each movement direction. The mean values calculated for VE (Figs. 1e3) were similar to studies performed by Lee et al. (2006) and Strimpakos et al. (2006). Yet our findings are in contrast to those
5
*
*
Control
*
*
Absolute error
Root mean square error
WAD ND
4
WAD D
Degrees
3
2
1
0
-1 Contant error
Variable error
-2
Fig. 2. The results of the various measures’ means and standard error of JPE from left rotation for each group (*p < 0.05). WAD D ¼ subjects with whiplash complaining of dizziness and WAD ND ¼ subjects with whiplash not complaining of dizziness.
0 Contant error
Variable error
Absolute error
Root mean square error
-1
Fig. 3. The results of the various measures’ means and standard error of JPE from right rotation for each group (*p < 0.05). WAD D ¼ subjects with whiplash complaining of dizziness and WAD ND ¼ subjects with whiplash not complaining of dizziness.
of Michaelson (2004) who found significant differences in the VE between a whiplash and control group. However, there were methodological differences in testing. These researchers used eight trials in each rotation direction and the subjects were instructed to perform movements as fast as possible. In contrast, procedures for the data set analysed in this study included use of a natural speed of movement and three trials. Thus it is difficult to determine the source of difference in the findings of VE and it would be premature to discard it on the basis of the negative findings in this current study. A potential limitation of this study is the use of a previous data set. The data used were from a population of neck pain subjects with whiplash injury and measurements were limited to HRA to neutral from extension and rotation. Future research should also consider the usefulness of the different error calculations in subjects with idiopathic neck pain, as it is in this group that more inconsistency in results has been observed (Rix and Bagust, 2001; Lee et al., 2005). It could also consider different methodologies and procedures for this specific test and the utility of the various mathematical calculations in other measures of cervical kinaesthetic sense such as movement detection thresholds (Taylor and McCloskey, 1988) and reproduction of active movement tasks (Kristjansson et al., 2004). It has been shown that the measure of AE in the test of HRA to neutral is sensitive to change with interventions either directed towards cervical impairments (Heikkila¨ et al., 2000; Jull et al., 2007) or sensorimotor deficits (Revel et al., 1994; Jull et al., 2007). Nevertheless, the results of this study overall would suggest that when assessing HRA in future studies, use of CE in
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combination with AE (or RMS) might be justified given their different properties and evidence of differences in findings between groups and movement directions. References Brumagne S, Lysens R, Verschueren S, Swinnen S. The role of paraspinal muscle spindles in lumbosacral position sense in individuals with and without low back pain. Spine 2000;25:989e94. Clark FJ, Larwood KJ, Davis ME, Deffenbacher KA. A metric for assessing acuity in positioning joints and limbs. Experimental Brain Research 1995;107:73e9. Heikkila¨ H, A˚stro¨m PG. Cervicocephalic kinesthetic sensibility in patients with whiplash injury. Scandinavian Journal of Rehabilitation Medicine 1996;28:133e8. Heikkila¨ HV, Wenngren BI. Cervicocephalic kinesthetic sensibility, active range of cervical motion, and oculomotor function in patients with whiplash injury. Archives of Physical Medicine and Rehabilitation 1998;79:1089e94. Heikkila¨ H, Johansson M, Wenngren BI. Effects of acupuncture, cervical manipulation and NSAID therapy on dizziness and impaired head repositioning of suspected cervical origin: a pilot study. Manual Therapy 2000;5:151e7. Jull G, Falla D, Treleaven J, Hodges PW, Vicenzino B. Retraining cervical joint position sense: the effect of two exercise regimes. Journal of Orthopaedic Research 2007;25:404e12. Koumantakis GA, Winstanley J, Oldham JA. Thoracolumbar proprioception in individuals with and without low back pain: intratester reliability, clinical applicability, and validity. Journal of Orthopaedic and Sports Physical Therapy 2002;32:327e35. Kristjansson E, Dall’Alba P, Jull G. A study of five cervicocephalic relocation tests in three different subject groups. Clinical Rehabilitation 2003;17:768e74. Kristjansson E, Hardardottir L, Asmundardottir M, Gudmundsson K. A new clinical test for cervicocephalic kinesthetic sensibility:
‘‘the fly’’. Archives of Physical Medicine and Rehabilitation 2004; 85:490e5. Lee HJ, Nicholson LL, Adams D, Bae S. Proprioception and rotation range sensitization associated with subclinical neck pain. Spine 2005;30:E60e7. Lee H, Teng C, Chai H, Wang S. Testeretest reliability of cervicocephalic kinaesthetic sensibility in three cardinal planes. Manual Therapy 2006;11:61e8. Loudon JK, Ruhl M, Field E. Ability to reproduce head position after whiplash injury. Spine 1997;22:865e8. Michaelson P. Sensorimotor Characteristics in Chronic Neck Pain. Thesis Umea˚: University of Umea˚; 2004. Revel M, Andre-Deshays C, Minguet M. Cervicocephalic kinesthetic sensibility in patients with cervical pain. Archives of Physical Medicine and Rehabilitation 1991;72:288e91. Revel M, Minguet P, Gergory J, Vaillant Manuel L. Changes in cervicocephalic kinesthesia after a proprioceptive rehabilitation program in patients with neck pain: a randomized controlled study. Archives of Physical Medicine and Rehabilitation 1994;75:895e9. Rix GD, Bagust J. Cervicocephalic kinesthetic sensibility in patients with chronic, nontraumatic cervical spine pain. Archives of Physical Medicine and Rehabilitation 2001;82:911e9. Schmidt RA, Lee TD. Methodology for studying motor performance. In: Schmidt RA, Lee TD, editors. Motor control and learning: a behavioural emphasis. New York: Human Kinetics; 1999. p. 15e40. Strimpakos N, Sakellari V, Gioftsos G, Kapreli E, Oldham J. Cervical joint position sense: an intra- and inter-examiner reliability study. Gait and Posture 2006;23:22e31. Taylor J, McCloskey D. Proprioception in the neck. Experimental Brain Research 1988;70:351e60. Treleaven J, Jull G, Sterling M. Dizziness and unsteadiness following whiplash injury: characteristic features and relationship with cervical joint position error. Journal of Rehabilitation Medicine 2003;35:36e43. Treleaven J, Jull G, LowChoy N. The relationship of cervical joint position error to balance and eye movement disturbances in persistent whiplash. Manual Therapy 2006;11:99e106.
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Diary of events 2nd World Congress on Manual Therapy and Sport Rehabilitation, The Spine II, in Roma Italy 6the8th of February 2009 www.newmaster.it Tel: þ3906 51600107 Fax: þ3906 51882443 MSc Conference Day Lifestyle, Physical Activity and Health Learn more about contemporary health promotion issues by attending this topical interactive conference day. The day will include topical presentations delivered by public health professionals including; managers and strategists, clinicians and researchers. Date: 23rd February, 2009 Venue: University of Hertfordshire, Hatfield, Herts, UK or virtual attendance from your home or workplace via Elluminate. Cost: £120 or £60 for virtual attendance Details and bookings contact: Jane Simmonds j.1.simmonds @herts.ac.uk or Karen Wells
[email protected] Back and beyond Theme The lumbar spine and pelvis Dates Sat 28e29th March 2009 Venue East Midlands Conference Centre, Nottingham For more details visit www.physiofirst.org.uk NZMPA biennial scientific conference, Heritage Hotel, Rotorua, New Zealand 28, 29 & 30 August 2009.
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The theme is ‘Striving for Excellence in OMT’ & also celebrating 40 years of Manual Therapy in New Zealand. The conference co-coordinator is Vicki Reid, Phone 0800 646 000 or 09 476 5353 Fax 09 476 5354 e-mail:
[email protected] Website: www.nzmpa.org.nz NOI International conference UK and Ireland Nottingham UK e April 15e17, 2010 Dublin IRELAND April 21e23, 2010 For further details www.noi2010.com Fax þ 3906 51882443 Janet G. Travell, MD Seminar Series, Bethesda, USA For information, contact: Myopain Seminars, 7830 Old Georgetown Road, Suite C-15, Bethesda, MD 20814-2432, USA. Tel.: þ1 301 656 0220; Fax: þ1 301 654 0333; website: www.painpoints.com/seminars.htm E-mail:
[email protected] If you wish to advertise a course/conference, please contact: Karen Beeton, Associate Head of School (Professional Development), School of Health and Emergency Professions, University of Hertfordshire, College Lane, Hatfield, Herts AL10 9AB, UK. E-mail:
[email protected] There is no charge for this service.
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Letter to the Editor
Response to Butler and Coppieters 2007, Letter to the Editor: Clinical neurodynamics e Throwing the baby out with the bath water I agree entirely with the comments by Butler and Coppieters (2007) that central mechanisms are relevant in neurodynamic testing (Shacklock, 1995) and, of late, this has always been my position (Shacklock, 1999a,b). That is why I presented these aspects as forming the context in which neurodynamic movements are applied (Shacklock, 2005, p. 12). I have stated that neurodynamic tests are really psychophysical manoeuvres that can be modified by many things including the cognitive and contextual and, as such, I proposed clinical techniques to take this into account (Shacklock, 2005, p. 113e114). So on this aspect we agree. However, I have no problem with focusing on an aspect of neurodynamics and to do so constitutes no statement that other aspects are not involved. To say that to omit these aspects left the Editorial lacking was to miss the point of the Editorial which was to make certain specific statements about neurodynamics and plenty of modern evidence in support was presented. There is too little space to discuss Butler’s and Coppieter’s comments in detail but their statement that responses to structural differentiation may have little to do with mechanical alterations in neural tissue I feel throws the baby out with the bath water. Structural differentiation is the key means by which we determine neurodynamic influences in diagnosis and, in my opinion, this should remain the case. In some regions of the body, there is good evidence for the mechanical validity of differentiation, e.g. in cadavers and with realtime ultrasound imaging (McLellan and Swash, 1976; Shacklock and Wilkinson, 2001; Coppieters et al., 2006a). Furthermore, Coppieters et al. (2005, 2006b) showed that it may be used to good effect in differentiation of muscle and nerve, at least in acute experimental
DOI of original article: 10.1016/j.math.2007.01.001. 1356-689X/$ - see front matter doi:10.1016/j.math.2008.01.002
muscle pain. Interestingly, these latter studies did not involve measurement of central or psychosocial mechanisms. Nevertheless, without structural differentiation we have no decent clinical evidence of a neurodynamic mechanism above musculoskeletal or others. Hence, to say that the response could be due to psychosocial or central mechanisms is fine, once we have a response that shows a neurodynamic mechanism. From a clinical methods point of view, as soon as the test response is likely to involve neurodynamics (i.e. positive with differentiation) we may then ask if it involves mainly psychosocial or physical mechanisms or combinations of both, weighing up the balance of the evidence. But unless we do structural differentiation as a natural and routine part of neurodynamic testing, we cannot even be sure if we have specifically a neurodynamic test to work with. And in the end, many of our patients do have physical problems that need specific mechanical evaluation and treatment. References Butler D, Coppieters M. Neurodynamics in a broader perspective [Letter to the Editor]. Manual Therapy 2007;12(1):e7e8. Coppieters M, Alshami A, Babri A, Souvlis T, Kippers V, Hodges P. Strain and excursion of the sciatic, tibial, and plantar nerves during a modified straight leg raising test. Journal of Orthopaedic Research 2006a;24(9):1883e9. Coppieters M, Alshami A, Hodges P. An experimental pain model to investigate the specificity of the neurodynamic test for the median nerve in the differential diagnosis of hand symptoms. Archives of Physical Medicine and Rehabilitation 2006b;87(10):1412e7. Coppieters M, Kurz K, Mortensen T, Richards N, Skaret I, McLaughlin L, Hodges P. The impact of neurodynamic testing on the perception of experimentally induced muscle pain. Manual Therapy 2005;10(1):52e60. McLellan D, Swash M. Longitudinal sliding of the median nerve during movements of the upper limb. Journal of Neurology, Neurosurgery and Psychiatry 1976;39:556e70. Shacklock M. Neurodynamics. Physiotherapy 1995;81:9e16.
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Shacklock M. Central pain mechanisms; a new horizon in manual therapy. Australian Journal of Physiotherapy 1999a;45:83e92. Shacklock M. The clinical application of central pain mechanisms in manual therapy. Australian Journal of Physiotherapy 1999b;45:215e21. Shacklock M. Clinical neurodynamics. Oxford: Elsevier; 2005. Shacklock M, Wilkinson M. Can nerves be moved specifically? In: Proceedings of the 11th biennial conference of the musculoskeletal physiotherapists’ association of Australia, Adelaide, Australia; 2001.
Michael Shacklock 118 King William Street, 6th Floor, Adelaide SA 5000, Australia Tel.: þ61 8 8212 4886; fax: þ61 8 8212 8028. E-mail address:
[email protected] 4 December 2007
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Book review Movement, Stability & Lumbopelvic Pain, Vleeming A, Mooney V, Stoeckart R. Churchill Livingstone (2007). 658 pp., price £59.99, ISBN: 9780443101786 This multi-author book (48 contributors) claims, as the editors stated in the preface, to provide the latest evidence-based relevant new data on the lumbopelvic area. However, the results of scientific research evolve so quickly that for some parts of this book the evidence is already out of date. In comparison to the first edition this second edition has been enlarged considerably. The book is now divided into six parts. The first part begins with biomechanical, clinicaleanatomical and evolutionary aspects in 13 chapters separated into two sections. Part II considers insights in function and dysfunction of the lumbopelvic region, and involves six chapters. In part III diagnostic methods are discussed in three sections containing nine chapters. The first section debates mainly the imaging of the sacroiliac joint and in the last chapter the relation of the pelvic girdle with the lumbar spine is discussed. In part IV the editors address in three chapters the European guidelines concerning prevention, acute and chronic LBP and finally diagnosis and treatment of pelvic girdle pain. Part V includes effective training and treatment which is described in seven chapters distributed over three sections. In the first two sections psychological, social and motivational aspects as well as motor control features are described while in the third section different views on effective treatment and training are discussed. Part VI integrates in two chapters’ different views and opinions when dealing with a complex system as the lumbopelvic region. One of the critical remarks on the first edition was the absence of the relationship between pelvic pain and low
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back complaints. The editors have attempted to reduce this deficiency, however, they succeed only to a limited level. The first and second chapter of part III about differential diagnosis of low back pain and the asymmetrical overload syndrome does not reflect modern opinions in relation to pelvic and low back pain problems. For example, the current tendency for classifying pelvic and low back pain into subgroups of which pelvic girdle pain could be an evident example is lacking entirely. Another critical note about the previous edition was the strongly impairment-related approach to the management of lumbopelvic pain. In part V of the present edition a timorous attempt is made to introduce the biopsychosocial model, however, it is only mentioned in a marginal way in the integrated section. The difference in level of the contributions leads to an unbalanced impression of the book. All chapters included in this book are more or less isolated. In part VI an attempt is made to integrate different views, opinions and the therapeutic approach to the treatment of pelvic girdle pain and described as a case report. However, a final contemplative chapter with a reflection of the presented knowledge and insights as well as an opinion of future developments about lumbopelvic pain in relation to low back pain would be more desirable. Despite of these limitations this book gives a comprehensive overview of lumbopelvic pain and I recommend it for clinicians more then for researchers. Peter van der Wurff, PhD, PT, MT Military Rehabilitation Centre, Doorn, The Netherlands Tel.: þ31 343 474 507. E-mail address: peterwurff@hotmail.com 7 January 2008
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Book review Manual Therapy for the Peripheral Nerves, Barral Jean-Pierre, Croibier Alain. Churchill Livingstone, Elsevier (2007). 270 pp., price £ 29.99, ISBN: 9780443103070 The topic of this book is interesting. I think this area of clinical practice is somewhat on the fringe of ‘manual therapy’, so the writing style is not what you would expect from most modern health textbooks, i.e. not supported by references. The first three chapters describe in a fairly superficial way the general anatomy, physiology and functional faults that may occur in the peripheral nervous system. This is interesting, nicely aided by diagrams, but I was left wondering if the information given is up to date and completely believable, and with no references, I couldn’t check. Chapter 4 covers treatment of the peripheral nerves, a very small part of this textbook, which for a title suggesting an in-depth presentation of such, this was disappointing. In the following chapters 5e8, attention is given to the large groups of peripheral
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nerves in the body: cervical plexus, brachial plexus, lumbar plexus and sacral plexus. These chapters are interesting and well designed with images and photographs to illustrate the information presented. I found this part of the book very useful as a revision aid to peripheral nerves, but I still struggled with the lack of references and evidence to support the text. I would like to explore some of the ideas brought up here more fully, but my own experience in clinical practice casts doubt on treatment of peripheral nerves in such a simplistic way? Unfortunately, I am not really reassured after reading this book; I would like more robust evidence to help me in these ‘grey’ areas of manual therapy. Tim McClune, D.O. Spinal Research Unit, University of Huddersfield, 30 Queen Street, Huddersfield HD1 2SP, UK E-mail address:
[email protected] 17 January 2008
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Book review Exercise therapy, prevention and treatment of disease, Gormley J, Hussey J. Blackwell Publishing (2005). 260 pp., price £ 25.99, ISBN: 1405105275 The aim of this book is to provide physiotherapists and undergraduate students with a useful reference text that informs about the application of exercise for various physical pathologies and diseases. This book is divided into two sections. The first section presents a general overview of the physiology of the cardiorespiratory and musculoskeletal systems, as well as cardiovascular adaptations to exercise. This section concludes with a chapter on exercise in diabetes and obesity. This first section is a concise summary of a wide area, but should not be considered a reference text for the physiology of exercise. Many of the reference texts used in this section are commonly used as required reading in undergraduate exercise physiology science courses. Therefore for the clinician this section should provide a nice summary for what they would have already learnt. The second section of the book moves into aspects of exercise testing and the basics of prescription. Further chapters in this section deal with
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specific conditions such as cardiovascular disease, respiratory disease, stroke, as well as behavioural aspects of facilitating long term exercise adherence. The exercise focus of this section is weighted towards aerobic testing and prescription, and often refers the reader to texts such as the ACSM guidelines for exercise testing and prescription. The editors and authors of this book have provided a text with an incredibly wide scope in only 250 pages. In providing such a wide summary, some detail is missing, however, the intent of this book is to be as a reference text for clinicians who have already covered the source material, or undergraduates who are getting a general overview. In this context, the book can be considered to be a success. Paul Marshall Exercise Rehabilitation Clinic, Tamaki Campus, Private Bag 92019, Manukau City, Auckland, New Zealand Tel.: þ64 9 373 7599. E-mail address:
[email protected] 4 February 2008
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Book review Physiotherapy for children, Pountney Teresa. Butterworth Heinemann, Elsevier (2007). 360 pp., price: £ 39.99, ISBN: 9780750 68886 4 The book aims at undergraduate students and qualified physiotherapists starting a career in paediatrics, in other words novices in the field of paediatric physiotherapy. All contributing authors work in the United Kingdom and are considered experts in their field. The book contains 8 parts (21 chapters) with the following titles: Working with children, Assessment and outcome measures, Neurology, Acquired brain injury, Musculoskeletal, Cardio-respiratory, Oncology and palliative care and Child and adolescent mental health, covering a large spectrum of clinical paediatrics. The chapters are structured similarly beginning with background information followed by a description of the clinical pattern, assessment strategies, interventions (multidisciplinary), and finishing with case studies and an extensive reference list. The case studies in each chapter are a strong didactic tool especially for physiotherapy novices. Except for the chapters that describe ‘delivery of care’ and ‘physiotherapy at the intensive care unit’, which focus specifically on the legal and professional situation in the UK, all other chapters are of a more generic nature and can be appreciated in physiotherapy
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settings outside the UK as well. The chapters, although similar in set up differ considerable in content and detail, some are primarily symptom driven (e.g. cardio pulmonary section) while others are ‘diagnosis’ oriented (e.g. musculoskeletal section) or age related (neonatal section). Interventions are rather conventional (muscle stretching in musculoskeletal conditions) and lack innovations (e.g. (an-)aerobic exercise training in childhood chronic conditions). ‘Outcome measures and measurement techniques’ are extensive in ‘clinical gait analysis’ while e.g. muscle strength testing equipment e.g. handheld dynamometry are not addressed. Although extensive in some of its topics, the book never reaches the level of a textbook, at its best it is a well written selection of paediatric physiotherapy capita with a detailed, but conservative treatment approach. Janjaap van der Net Department of Paediatric Physiotherapy and Paediatric Exercise Physiology, University Children’s Hospital, University Medical Centre at Utrecht, Lundlaan 6, The Netherlands E-mail address:
[email protected] 5 February 2008
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Book review The physiology of the joints, Kapandji IA, Adalbert I. 6th ed. The upper limb, vol. 1. Churchill Livingstone Elsevier (2007). 361 pp., price £ 29.99, ISBN: 9780443103506 The books of Dr. Kapandji on ‘‘Physiologie articulaire’’, first published in French more than 30 years ago, rapidly became famous worldwide and were translated in 11 languages. This first volume of the sixth English edition concerns the upper limb and two more volumes will follow. Whereas the first five editions remained very similar, this new edition probably will be the start of a renewed longstanding success. The concept of the book remains unchanged, with simple but clear illustrations on the right page and the corresponding explanations on the left-hand page. For the first time the diagrams are printed in colour, but this is not the only, nor the main cosmetic change. Both text and illustrations have been largely reworked, new items were added, especially pronation, the supination, the biomechanics of the wrist and the movements of the thumb have been thoroughly revised. Clinical
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and functional aspects have also been extended. The result is a book with over 150 new pages and dozens of new illustrations. Some terminology problems of the French edition due to the use of older French anatomical terminology have been corrected in the English translation by Dr. L. Honore´. The book ends with instructions to assemble a working cardboard model of the hand. Not easy! I am convinced this is a much improved and up to date edition which should rapidly replace the older editions. This book is a must for physicians, physiotherapists, manual therapists, osteopaths and all practitioners involved in rehabilitation. E. Barbaix Vrije Universiteit Brussel, Department of Human Anatomy, Brussels, Belgium E-mail address:
[email protected] 5 February 2008
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Masterclass
Physical and psychological aspects of whiplash: Important considerations for primary care assessment, Part 2 e Case studies Michele Sterling a,b,* a
Centre of National Research on Disability and Rehabilitation Medicine (CONROD), The University of Queensland, Mayne Medical School, Herston Road, Herston, QLD 4066, Australia b Division of Physiotherapy, The University of Queensland, QLD 4072, Australia Received 20 March 2008; accepted 20 March 2008
Abstract Whiplash is a heterogenous and in many, a complex condition involving both physical and psychological factors. Primary care practitioners are often the first health care contact for individuals with a whiplash injury and as such play an important role in gauging prognosis as well as providing appropriate management for whiplash injured patients. It is imperative that factors associated with poor outcome are recognized and managed in the primary care environment at the crucial early acute stage post-injury. This paper presents 2 case studies of individuals with acute whiplash pain. The case studies illustrate the heterogeneity of the whiplash condition and the importance of clinical assessment that includes consideration of both physical and psychological manifestations. They also demonstrate the important role physiotherapists’ play in the management of people with whiplash, particularly in the early post-injury stage. Crown Copyright Ó 2008 Published by Elsevier Ltd. All rights reserved. Keywords: Whiplash associated disorders; Central hyperexcitability; Posttraumatic stress; Assessment
1. Introduction Whiplash is a common and costly consequence following a motor vehicle crash, with up to 60% of those injured reporting persistent neck pain and disability (Rebbeck et al., 2006; Sterling et al., 2006). In recent times, there has been an accumulation of research data demonstrating whiplash to be a heterogeneous and complex condition involving varying degrees of both physical and psychological manifestations. Importantly some of these features, for example, hyperalgesia, movement loss, posttraumatic stress symptoms, moderate/ * Centre of National Research on Disability and Rehabilitation Medicine (CONROD), The University of Queensland, Mayne Medical School, Herston Road, Herston, QLD 4066, Australia. Tel.: þ61 7 3365 5344; fax: þ61 7 3346 4603. E-mail address:
[email protected]
severe levels of pain and disability are predictive of poor functional recovery (Scholten-Peeters et al., 2003; Rebbeck et al., 2006; Sterling et al., 2006). Musculoskeletal clinicians play an important role in the early management of whiplash injury, particularly in the primary care environment where many injured people will seek treatment for their condition. In the accompanying paper to this one, the heterogeneous clinical presentation of acute and chronic whiplash was outlined and suggestions made for the assessment of this condition. It was argued that some patients will present with a ‘less complex’ clinical presentation and these patients should respond well to shortterm physiotherapy interventions. In contrast and at the other end of the spectrum, there are the group of patients whose clinical presentation is complicated by the additional presence of widespread sensory hypersensitivity and symptoms of posttraumatic stress (Fig. 1). This
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Fig. 1. An outline of factors that is indicative of 2 different clinical presentations of whiplash. It is argued that the ‘more complex’ presentation will require a more intensive and interdisciplinary approach to management.
group will likely require a more concerted approach to their management based on early identification of these factors and others associated with poor outcome. In order to illustrate the varied clinical presentation of whiplash and the assessment required, 2 case studies will be presented. Acute whiplash injury has been selected for the outline of these case studies, in order to emphasize the importance of this stage of the whiplash process and that effective assessment and management may help to prevent the development of chronicity in those at risk. In order to illustrate the ‘overall’ management of acute whiplash, in depth discussion of specific physical interventions is not provided, instead readers are provided with appropriate references with more detailed discussion of specific techniques.
2. Case studies 2.1. Case 1: ‘less complex’ whiplash presentation 2.1.1. Patient interview and history Jane, 30-year-old female; married; 1 child (3 years old). Work: Personal assistant to CEO of advertising company. History: Jane was on her way home from work 10 days ago when her car was rear-ended whilst stopped at a red traffic light. Jane felt slight pain in her neck at the time of the accident and after organising the car to be towed away she went home. That night she could feel her neck getting stiff. She went to bed early but
when she awoke the next morning, she could barely turn her neck. Jane managed to rest that day and her partner cared for their child. Jane took the following 2 days off work (sick leave). She then returned to work and reports that she ‘struggles’ through her day before collecting her child from childcare and returning home to rest as much as she can. Jane is usually very active and goes to gym classes 3 times a week as well as playing hockey on the weekends but has not been able to do so since the car accident due to neck pain. However, she has been able to ride a stationary bike at home for about 15 min at a time. Jane presents to the physiotherapist 10 days after the accident as she feels that her neck should be better by now and she is worried since her friend experienced a similar injury and was unable to play any sports for 12 months. Jane has not had any radiological investigations. She has taken Panadol as necessary with some reported relief. Jane’s sleep is not disturbed by pain and her pain is no worse with cold. Pain: left sided neck pain (VAS: 5/10); left sided frontal headache (VAS: 4/10). Patient Specific Functional Scale (PSFS) (Westaway et al., 1998): Picking up child: 4/10. Working at office desk (longer than 30 min): 6/10. Reading (longer than 30 min): 6/10. Neck Disability Index (NDI) (Vernon and Mior, 1991): 32/100. Impact of Events Scale (IES) (Horowitz et al., 1979): 7 (Note: the IES is preferred to the IES-R for clinical
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use as cut-off scores for levels of posttraumatic stress symptoms have been reported). General Health Questionnaire-28 (GHQ-28): 19 (just below threshold of 23/24) (Goldberg, 1978). Self-reported Leeds Assessment of Neuropathic Signs and Symptoms scale (S-LANSS) (Bennett et al., 2005): 6.
2.1.2. Physical examination Posture: can actively correct posture to good position when facilitated. Neck range of movement (measured using gravity dependent goniometer): left rotation: 50 ; extension: 30 . Right rotation and flexion: full. Cervical muscle control: tested using the craniocervical flexion test (Jull et al., 2007). Could achieve 24 mm Hg before loss of correct movement pattern and marked superficial muscle activity. Shoulder girdle muscle control: good control in prone lying, sitting and with arm movement (Jull et al., 2007). Postural control (Treleaven, 2007): joint position error e less than 3 all directions. Manual examination (Maitland et al., 2001): decreased movement and pain (VAS: 4/10) at C2/3 segment on the left side with localised hyperalgesia only. Clinical neurological examination (muscle power, reflexes, sensation): nothing abnormal detected. Brachial plexus provocation test (BPPT) (Elvey, 1997; Sterling et al., 2002): elbow extension 15 from 180 (bilaterally) at pain threshold (VAS: 1/10).
2.1.3. Key findings from the examination Moderate levels of pain and disability. Some psychological distress (GHQ-28 approaching threshold); anxiety about not being able to return to sport. No symptoms of posttraumatic stress: low scores on the IES. No evidence of central hyperexcitability (hyperalgesia is localised to the cervical spine and is not widespread; S-LANSS score is <12; no hypersensitivity with the BPPT; no sleep disturbance due to pain; condition is not irritable). Indications of a localised condition of the cervical spine associated with movement loss and impaired muscle control of the neck.
2.1.4. Prognosis The presence of moderate levels of pain and disability is a prognostic indicator for poor recovery (Kamper
et al., in press). However, Jane’s levels of psychological distress are low (below threshold); she reports no symptoms of posttraumatic stress; there is no evidence of central hyperexcitability and neck ROM is not markedly restricted. Therefore it would be expected that Jane should recover well. 2.1.5. Management plan At this stage, the physiotherapist should be able to undertake the management of this patient. There is little to indicate that referral to other heath care providers is indicated. Cognitive management should include: assurance about prognosis and that full recovery is expected; provide awareness of mechanisms underlying the condition; provide an explanation to Jane of the proposed management plan (see below) and its expected effects. Physical management should be a multimodal approach. This would primarily involve improvement of cervical movement, retraining of motor control commencing in an unloaded supine position but progressing rapidly to functional and weight bearing activities (for further detail see: Sterling et al., 2001; Jull et al., 2007; Stewart et al., 2007). Gentle manual therapy to C2/3 could also be included for its hypoalgesic effect on the cervical spine (Sterling et al., 2001). As pain and disability decreases, a graduated cardiovascular fitness program could be introduced with the aim of restoring full sporting activities. In this case, this is little to indicate a prolonged recovery. Therefore it would be expected that improvements would be seen quickly (as determined by clinically relevant changes on pain and functional outcomes) and that physiotherapy treatment would not be of a long-term nature. 2.2. Case 2: ‘more complex’ whiplash presentation 2.2.1. Patient interview and history Patricia, 38-year-old female, married; 2 children (15 and 10 years). Work: Administration assistant. History: 6 weeks ago, Patricia was involved in a motor vehicle crash where her car was hit on the rear passenger driver’s side, by a car that ran a red light. She felt immediate sharp pain in her neck and head. The car was extensively damaged and she was taken to hospital where X-rays revealed no fracture or dislocation and she was sent home with analgesics. Patricia went to her General Practitioner (GP) the next day as her pain which had spread into her right arm was reaching an intolerable level. He prescribed Voltaren and Panadeine Forte and advised her to take a week off work. After this time, Patricia then attempted to return to work
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but this exacerbated her pain; she couldn’t concentrate and was experiencing some light-headedness. She has not since returned to work. She is not sleeping well due to neck pain and reports that she can’t get to sleep due to thoughts about the accident. Patricia returned to her GP who has referred her to physiotherapy. Usually, Patricia has a busy life with full-time work and caring for her children. She finds time to walk approximately 5 km, 3 times a week but has been unable to do this since the accident. Pain: Constant neck (8/10) and right arm (6/10) pain. Intermittent paraesthesia (3/10) in the right hand. PSFS (Westaway et al., 1998): Sitting longer than 10 min: 2/10. Turning head to look over right shoulder: 1/10. Washing-up: 1/10. NDI (Vernon and Mior, 1991): 52/100. IES (Horowitz et al., 1979): 30 (moderate symptoms of posttraumatic stress). GHQ-28 (Goldberg, 1978): 30 (above threshold of 23/ 24). S-LANSS (Bennett et al., 2005): 24 (>12, likely neuropathic component to the pain). In both case studies it could be argued that additional questionnaires that aim to measure other psychological substrates could be included (for example, fear avoidance beliefs or catastrophisation). The above questionnaires have been included in view of their use in the investigation of whiplash.
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10); left, elbow extension 20 from 180 ) at pain threshold (VAS: 2/10). Allodynia of right arm. 2.2.3. Key findings from the examination Moderate levels of pain and disability. Moderate psychological distress (GHQ-28 above threshold). Moderate levels of posttraumatic stress symptoms; IES score of 30. Evidence of central hyperexcitability and/or neuropathic pain condition (constant pain; irritable condition; S-LANSS score of >12; allodynia; marked hypersensitivity to the BPPT on the right side and protective posture may indicate mechanosensitivity of peripheral nerve tissue although nerve conduction appears normal, Hall and Elvey, 1999). Indications of a complex presentation involving central hyperexcitability; possible peripheral nerve tissue involvement (mechanosensitivity) as well as moderate levels of distress, particularly posttraumatic stress.
2.2.4 Prognosis There are several adverse prognostic indicators associated with this clinical presentation. In addition to moderate/high levels of pain and disability, there is evidence of central hyperexcitability, marked neck movement loss and moderate levels of posttraumatic stress. Patricia is at risk of developing chronic pain and disability as a result of her injury. It is important that any treatment plans take this into account.
2.2.2. Physical examination Posture: right shoulder elevated, cradling right arm. Arm pain increases with shoulder depression. Neck range of movement (measured using gravity dependent goniometer): left and right rotations: 20 ; extension: 10 ; flexion: 10 . Cervical muscle control: poor pattern of craniocervical flexion; marked activity in superficial flexors (Jull et al., 2007). Unable to formally test with biofeedback unit due to the presence of allodynia. Shoulder girdle muscle control: not tested due to pain provocation with shoulder depression. Postural control (Treleaven, 2007): joint position error e unable to test due to lack of neck ROM. Balance e unsteadiness in tandem stance. Manual examination (Maitland et al., 2001): unable to effectively perform as neck is allodynic. Clinical neurological examination (muscle power, reflexes, sensation): generalized decrease in light touch sensation over right arm but not specific to a particular dermatome. BPPT (Elvey, 1997; Sterling et al., 2002): right, elbow extension 60 from 180 at pain threshold (VAS: 8/
2.2.5 Management plan This is a critical time period for Patricia’s condition. The complex nature of her condition indicates that an interdisciplinary approach to her management will be required. It is now 6 weeks post-injury and the patient is reporting moderate levels of posttraumatic stress symptoms. A psychological referral should be instigated such that further evaluation of the patient’s psychological status is undertaken. Guidelines recommend that trauma-focussed cognitive behavioural therapy delivered by a psychologist should be commenced (Forbes et al., 2007). The physiotherapist also plays a role and it is important that clear information is provided to the patient without further adding to her distress or catastrophising the condition. It is unlikely that a psychological approach to treatment alone will be sufficient to reduce pain (Blanchard et al., 2003), so it is also important that some pain relief is achieved via other means. Liaison with the GP would be indicated with the view to improve pain control via medication (Curatolo et al., 2006). Physical interventions such as active movement/exercises within pain limits, gentle manual therapy and modalities such as
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TENS may also assist in this regard (Skyba et al., 2003; Sluka et al., 2006). Whilst at this stage, treatment emphasis should be placed on the psychological and pain processing aspects of the condition, it is also important that treatment is directed to improving movement and function. This may take the form of advice and encouragement to commence gentle exercises of the neck as well as general activity as tolerated by pain (MAA, 2007), taking care not to overly provoke symptoms. The physiotherapist should also be aware that posttraumatic stress symptoms can influence activity levels of people with whiplash (Sterling and Chadwick, submitted for publication) and this should be taken into account. The physiotherapist may elect to defer more intensive rehabilitation (e.g., motor and postural control retraining) in order to decrease the burden on the patient until her posttraumatic stress symptoms improve. In this case, liaison with the treating psychologist would be essential such that the patient’s progress be monitored and more intensive physical treatment commenced at an appropriate time. Due the complexity of this whiplash presentation, it is clear that a more concerted approach to management is required. It is likely that the length of treatment time and the number of treatments will be greater than those required for case study 1. In both cases, progress should be monitored with validated outcome measures and treatment adapted in view of the individual patient’s progress. It can be seen that such an integrated approach to the management of this patient requires collaborative communication between the health care providers involved in her management. However, for this to occur the physiotherapist must consider the overall status of the patient and resist focusing on motor retraining only. 2.3. Summary These 2 distinct clinical presentations of acute whiplash injury highlight the importance of adequate and appropriate early assessment. Musculoskeletal clinicians play an important role in the assessment and management of both the physical and psychological aspects of this condition and are ideally placed to play a role in the co-ordination of care for patients such as this. References Bennett M, Smith B, Torrance N, Potter J. The S-LANSS score for identifying pain of predominantly neuropathic origin: validation for use in clinical and postal research. The Journal of Pain 2005; 6:149e58. Blanchard E, Hickling E, Devineni T, Veazey C, Galovski T, Mundy E, et al. A controlled evaluation of cognitive behaviour therapy for posttraumatic stress in motor vehicle accident survivors. Behaviour Research and Therapy 2003;41:79e96.
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