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Orthopaedics and Trauma Elsevier, ISSN: 1877-1327, http://www.sciencedirect.com/science/journal/18771327 Volume 25, Issue 5, Pages 317-396 (October 2011) 1
Editorial Board and Aims and Scope, Page i
Mini-Symposium: The Hand 2
(i) Anatomy of the carpus and surgical approaches, Pages 317-323 David Warwick, Mostayn Alam
3
(ii) Wrist fractures, Pages 324-335 Douglas A. Campbell, Tamsin C. Wilkinson
4
(iii) Injuries of the carpus, Pages 336-343 Helen Whalley, Ian McNab
5
(iv) Wrist arthroscopy, Pages 344-352 Javier Ferreira Villanova, Juan González Del Pino
Hip 6
Radiographic assessment of primary hip arthroplasty, Pages 353-362 Ruy E. da Assunção, Benjamin J.R.F. Bolland, Stuart Edwards, Leonard J. King, Douglas G. Dunlop
Shoulder 7
Acute first-time shoulder dislocation, Pages 363-368 Adam Rumian, Duncan Coffey, Simon Fogerty, Roger Hackney
Quiz 8
Radiology quiz, Pages 369-376 Ajay Sahu, Nanda Venkatanarasimha, Priya Suresh
Children's Orthopaedics 9
Physeal fractures: basic science, assessment and acute management, Pages 377-391 Emily R. Dodwell, Simon P. Kelley
CME Section 10
CME questions based on the Mini-Symposium on “The Hand”, Pages 392-393
11
Answers to CME questions based on the Mini-Symposium on “Asia Pacific”, Page 394
Book Reviews 12
Operative techniques in hand, wrist and forearm surgery, Page 395 Robert Farnell
13
Advanced reconstruction: knee, Page 395 David Calder
Orthopaedics and Trauma Orthopaedics and Trauma presents a unique collection of International review articles summarizing the current state of knowledge in orthopaedics. Each issue begins with a focus on a specific area of the orthopaedic knowledge syllabus, covering several related topics in a mini-symposium; other articles complement this to ensure that the breadth of orthopaedic learning is supplemented in a 4 year cycle. To facilitate those requiring evidence of participation in Continuing Professional Development there is a questionnaire linked to the mini-symposium that can be marked and certified in the Editorial office.
Editor-in-Chief D Limb BSc FRCS Ed (Orth) Leeds General Infirmary, Leeds, UK
Editorial Committee M A Farquharson-Roberts (Gosport, UK), I Leslie (Bristol, UK) M Macnicol (Edinburgh, UK), I McDermott (London, UK), J Rankine (Leeds, UK)
Editorial Advisory Board D C Davidson (Australia) J Harris (Australia) G R Velloso (Brazil) P N Soucacos (Greece) A K Mukherjee (India) A Kusakabe (Japan) M-S Moon (Korea) R Castelein (The Netherlands) R K Marti (The Netherlands) G Hooper (New Zealand)
A Thurston (New Zealand) E G Pasion (Philippines) L de Almeida (Portugal) G P Songcharoen (Thailand) R W Bucholz (USA) R W Gaines (USA) S L Weinstein (USA) M Bumbasirevic (former Yugoslavia)
MINI-SYMPOSIUM: THE HAND
(i) Anatomy of the carpus and surgical approaches David Warwick Mostayn Alam
Abstract Anatomy and surgical approaches are intimately related. In this article the authors describe the anatomy of the wrist in detail e vascular, neural, osseous, articular and ligamentous. This is followed by description of the surgical approaches to the distal radio-ulnar joint, distal radius, scaphoid and the universal dorsal approach to the carpus. The article is supported by illustrations throughout.
Keywords anatomy; carpus; surgical approach; wrist Figure 1 Anatomy of the TFCC and its components. The triangular fibrocartilage complex: triangular fibrocartilage, palmar and dorsal radioulnar ligaments, and the ulnar carpal ligaments.
Distal radio-ulnar joint anatomy Bone The sigmoid notch of the radius articulates with the ulnar head. Because there is a different centre of rotation of the head and notch there is some glide in the antero-posterior plane. The distal dome of the head articulates with the underside of the lunate and triquetrum; the central part of the TFCC acting as a cushion. The ulna is relatively longer than the radius (“ulnar variance”) with the forearm pronated; ulnar variance shortens in supination. About 20% of load across the wrist passes through ulno-carpal joint and 80% through the radio-carpal joint. Increasing ulnar variance by 2.5 mm increases ulno-carpal load to 40% whilst decreasing variance by 2.5 mm decreases ulno-carpal load to 5%. A long ulna is associated with ulno-carpal impaction (central TFCC perforation and luno-triquetral degeneration); a short ulna is associated with Kienbock’s disease (spontaneous avascular necrosis of the lunate).
meniscus homologue ulnar collateral ligament extensor carpi ulnaris subsheath origins of the ulno-lunate and luno-triquetral ligaments The TFCC arises along the ulnar aspect of the distal articular surface of the radius at the distal margin of the sigmoid notch. The anterior radio-ulnar ligament emerges from the anterior ulnar-distal corner of the notch and the posterior radio-ulnar ligament from the dorsal-ulnar-distal corner. The ligaments, which blend with the central disc, attach to the fovea which is a pit at the radial edge of the base of the ulnar styloid. If these ligaments are avulsed distally, the DRUJ becomes unstable; surgical reconstruction involves either re-attachment with a bone anchor via the surgical approach described below, or with a tendon graft mimicking the anatomical pathway as described by Adams. In addition to stabilizing the DRUJ, the TFCC allows the transmission of 20% of the axial load at the wrist (neutral ulnar variance). The periphery of the TFCC is well vascularized, whereas the central radial portion remains relatively avascular. Injuries to the peripheral aspect of this triangular plate heal better than the central portion. Central portion perforations, due to natural degeneration, traumatic impaction or erosion by a long ulnar head (impaction syndrome) are treated arthroscopically with the approach described below.
Triangular Fibrocartilage Complex The Triangular Fibrocartilage Complex (TFCC) is a complex conglomeration that acts as the major soft tissue stabilizer of the distal radio-ulnar joint (DRUJ) (Figure 1). The components of the TFCC include: dorsal radio-ulnar ligament anterior radio-ulnar ligament central articular disc
David Warwick MD FRCS FRCS (Orth) EDHS Consultant Hand Surgeon, Reader in Orthopaedics, University of Southampton, United Kingdom. Conflict of interest: none.
Tendons The ECU acts as a secondary stabilizer of the DRUJ and resists dorsal and ulnar translation of the ulnar head. It runs through a groove in the ulnar head and has its own subsheath (which is a component of the TFCC) (Figure 2). The retinaculum over the 6th compartment runs ulnarwards and palmarwards, blending into the anterior fascia and is separate from the subsheath. ECU is a pure ulnar deviator with the wrist in pronation and a pure extensor with the forearm in supination. The ECU is the only long extensor tendon which is not
Mostayn Alam BM BSc (Hons) Foundation Year One Doctor (FY1/Intern), Department of Paediatric Surgery, Addenbrookes Hospital, Cambridge University Hospitals NHS Foundation Trust, East Anglia Deanery Foundation Programme Cambridge, United Kingdom. Conflict of interest: none.
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The FCU (flexor carpi ulnaris) is an ulnar deviator and flexor of the wrist. It stabilizes the wrist in grip and hammering. Its insertion is augmented through the pisiform bone which acts in the same way as the patella of the knee. The EDM (Extensor Digiti Minimi) is the direct dorsal relation of the DRUJ capsule and runs within the 5th retinacular compartment (Figure 3).
Surgical approach to the distal radio-ulnar joint Indications Open TFCC attachment Open wafer excision TFCC anatomical reconstruction Ulnar head deletion (Darrach’s, SauveeKapandji, matched ulnar resection). NB these operations are to be avoided whenever possible due to the risk of incurable instability! Ulnar head replacement Fracture reconstruction
Figure 2 Schematic of the ECU subsheath (in red) (axial view). It is a component of the TFCC and houses the ECU tendon which acts as a secondary stabilizer of the DRUJ. The extensor retinaculum (in blue) courses over the ECU and distal ulna attaching to the pisiform and triquetrum.
Procedure An incision is made over the dorsum of the distal radio-ulnar joint, extending distally and slightly ulnarwards towards the styloid process of the 5th metacarpal (Figure 4). Take great care to avoid cutting or stretching the dorsal branches of the ulnar nerve which traverse this plane and which are vulnerable. The
contained by the extensor retinaculum; if it was then the forearm could not supinate and pronate because the distance between the 5th compartment (attached to the radius) and 6th compartment (ECU) would be fixed.
Figure 3
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extensor retinaculum is divided longitudinally over the EDM sheath (5th dorsal compartment), retracting the tendon radialwards. The retinacular pillaris undermined to the ulnar side of the EDM, elevating the retinaculum ulnarwards. The ECU subsheath is not disturbed. The DRUJ capsule and dorsal ulno-carpal capsule are now visible. The dorsal limb of the TFCC (dorsal radio-ulnar ligament) has to be imagined as a structure running transversely in the palpable dent between the ulnar head and the proximal edge of the luno-triquetral joint. A vertical capsulotomy is made into the DRUJ capsule, leaving a 5 mm cuff radialwards for later repair. Do not go further distal than the proximal edge of the transversely-running dorsal radioulnar ligament. Cut transversely and ulnarwards just proximal to the dorsal radio-ulnar ligament. Do not go further ulnar than the radial edge of the ECU sheath. The head is now exposed. The ulnar neck is exposed by extending the vertical capsulotomy proximally. To expose the distal edge of the TFCC (for re-attachment) make a transverse incision distal to the dorsal radio-ulnar ligament, again not further than the radial edge of the ECU sheath.
proximal row continuously adapt their position and orientation to ensure joint congruency between the radius and the distal carpal row. There are no direct tendon attachments to the proximal carpal row. As the hand tilts radially, the scaphoid flexes as there would otherwise be no space between the radius and trapezium; as the hand tilts ulnarwards the scaphoid extends to fill that space. Carpal height: the distance between the distal edge of the capitate and the proximal edge of the lunate is divided by the length of the 3rd metacarpal and is expressed as ratio which is usually €ck’s 0.540.03. The ratio is reduced in carpal collapse (e.g. Kienbo disease and scapho-lunate ligament failure). The articular surfaces between each row are defined by Gilula’s lines (Figure 5) which are disrupted in certain fractures, dislocations and ligament instabilities. The distal carpal row, being more stable, moves as a single unit. The five metacarpals of the hand find support on a rigid transverse arch which is formed by the distal row. The 1st metacarpaletrapezium joint is saddle shaped and allows the thumb to glide in an arc e opening the thumb out to hold a medicine ball and closing the thumb over to hold a ping-pong ball. Connections between the 2nd metacarpaletrapezoid and 3rd metacarpalecapitate are tight whereas 30e40 degrees of flexionextension occur at the 4th metacarpalehamate and 5th metacarpalehamate.
Anatomy of the carpus Radiological anatomy The carpus is a complex unit that links the hand and forearm. There are eight bones in the carpus, seven of which align themselves into two rows. The proximal row contains the scaphoid, lunate and triquetrum. The trapezium, trapezoid, capitate, and hamate are the components of the distal row. The pisiform, despite being a true carpal bone, is a sesamoid bone within the tendon of FCU. The scaphoid crosses both rows. The proximal carpal row is sometimes explained as an “intercalated segment” which is a mobile row between the relatively fixed forearm and distal carpal row. The three bones of the
Ossification: the ossific centre for the distal radius epiphysis appears at age 2 and fuses by age 16e18. The other bones develop ossification centres in clockwise order (looking at the right hand from behind, fully pronated). Ossification commences at the Capitate (1 month) proceeding in a clockwise direction: Hamate (1 year); Triquetrum (2e3 years); Lunate (4 years);
Figure 4
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Figure 5
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Scaphoid (4e6 years); Trapezium (4e6 years); Trapezoid (4e6 years); pisiform, (8e10 years). NB e in an adolescent, the incompletely ossified scaphoid can be mistaken for a scapho-lunate dissociation. Anomalies Anomalies include bipartite scaphoid e (confused with fracture), lunateetriquetrum coalition (usually asymptomatic) and os styloideum (accessory bone at the tip of the styloid). Extrinsic carpal ligaments These are discrete consolidations of the capsule, with the palmar ligaments stronger than the dorsal (Figures 6 and 7). They connect the radius and ulnar to the carpus, or carpal bones to other carpal bones, providing stability. Dorsal extrinsic carpal ligaments Dorsal radio-carpal ligament (radio-capitate, radio-triquetral) e if these rupture, a VISI (volar intercalated instability) can develop. Dorsal ulno-triquetral ligament e this supports the ulnar side of the carpus. Attenuation causes the carpus to supinate e commonly seen in rheumatoid and occasionally after trauma. Dorsal inter-carpal ligament (triquetrum to scaphoid and trapezoid) e this is split as part of the standard anatomical approach to the carpus; it may be used as a donor for tenodesis against palmar rotation of scaphoid. Figure 7 The palmar extrinsic ligaments.
Palmar extrinsic carpal ligaments Radio-scapho-capitate ligament e this attaches to the palmar edge of the radial styloid and is a fulcrum for scaphoid flexion. It is divided then carefully repaired during the palmar approach to scaphoid. It is clearly seen in arthroscopy. It is important not to remove it’s attachment by enthusiastic radial styloidectomy, lest radio-carpal subluxation occurs. Long radio-lunate ligament e this restrains the lunate from dislocating palmarwards. Ligament of Testut (radio-scapho-lunate) e this is not a ligament at all but a consistent synovial fold. It has no stabilizing function, but is a useful landmark for the scapho-lunate interosseous ligament in wrist arthroscopy. Short radio-lunate ligament e this runs from the ulnar edge of the distal radius to the lunate, blending ulnarwards with the ulno-lunate ligament. Ulno-carpal ligament (comprising ulno-capitate, ulno-lunate, ulno-triquetral ligament) e this blends into anterior radio-lunate ligament (i.e. the anterior limb of the TFCC). The ulno-triquetral ligament blends into the subsheath of ECU which is itself also part of the TFCC. Space of Poirier e this is the gap between lunate and mid-carpal joint through which lunate can dislocate anteriorly. Intrinsic ligaments These ligaments connect the inner adjacent surfaces of two bones, rather than connecting them across their outer surface. Scapho-lunate interosseous ligament e this is C shaped such that there is a space rather than a ligament when viewed from the mid-
Figure 6 The dorsal extrinsic ligaments.
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carpal joint arthroscopically. It is thickest dorsally. Attenuation or rupture may allow forward rotation of the scaphoid and dorsal tilt of the lunate (DISI or dorsal intercalated segment instability). Luno-triquetral interosseous ligament e this is also C shaped and hollow when viewed from the mid-carpal joint arthroscopically. It is thickest in its palmar limb. Attenuation or rupture may cause a VISI deformity. Capitateehamate, trapezoidecapitate; trapeziumetrapezoid ligaments e these connect the bones of the distal carpal row which essentially move as one unit.
It then passes dorsally and distally to innervate the skin over the back of the ulnar side of the palm and the back of the little and ring fingers. It may be damaged by a surgical approach to the distal ulna, ulnar head or triquetrum/hamate. It is also vulnerable during insertion of an arthroscope. The superficial radial nerve emerges from beneath the brachioradialis about 5 cm proximal to the radial styloid and then branches repeatedly to innervate skin over the back of the anatomical snuffbox and radial side of the dorsum of the hand. Surgery to the 1st dorsal compartment (de Quervain’s release) and the thumb CMC joint can lead to injury of this nerve. The palmar cutaneous branch of the median nerve emerges from the main trunk about 5e7 cm proximal to the transverse wrist crease and then runs distally to innervate a patch of skin at the base of the thenar eminence. It is vulnerable in scaphoid and thumb CMCJ surgery and in excision of a palmar wrist ganglion.
Nerve supply of the wrist Carpal innervation and wrist neurectomy The central part of the wrist joint is supplied by the terminal branches of the posterior interosseous and anterior interosseous nerves. These are surgically divided in a neurectomy procedure. The posterior interosseous nerve is readily found in the floor of the fourth dorsal compartment beneath the long finger extensors and alongside a terminal branch of the posterior interosseous artery. The anterior interosseous nerve, having supplied pronator quadratus, terminates in the carpus and is found just anterior to the interosseous membrane. It is usually divided surgically through the dorsal approach by perforating the interosseous membrane. The radial side of the wrist is supplied by nerves which descend from the median nerve, palmar cutaneous branch, superficial radial nerve and terminal lateral cutaneous nerve of the forearm. There are also fibres running alongside the radial artery. During a neurectomy procedure, a hockey shaped incision alongside the FCR tendon is used to expose the radial artery which is stripped of the peri-vascular sheath as it approaches the wrist; the exterior surface of the carpal extrinsic ligaments is then brushed clear of any tenuous fascial attachments. The ulnar side of the carpus is innervated by branches descending from the ulnar nerve and the dorsal branch of the ulnar nerve. Through a mid-ulnar approach the fascial attachments to the periosteum-capsule are brushed clear.
Blood supply of the wrist The blood supply to the wrist and carpus derives from the regional vessels (Figure 8). Circulation is achieved through the radial, ulnar as well as the anterior interosseous and deep palmar arches. These can be used as flaps to vascularize the scaphoid and lunate. The extraosseous arterial blood supply is formed via an anastomotic network of three dorsal and three palmar arches connected in a longitudinal fashion at the medial lateral borders of the radial and ulnar arteries. Apart from transverse and longitudinal anastamoses, there are also dorsal to palmar connections between the dorsal and palmar branches of the anterior interosseous artery. The radial artery accesses the dorsal aspect of the carpus by passing between FCR and the abductor pollicis longus (APL) and extensor pollicis brevis (EPB) tendons within the anatomical snuffbox. Prior to this, it gives off a superficial palmar branch which communicates with the ulnar artery (superficial arch). Within the hand, it forms the deep palmar arch. The dorsal carpal branch of the radial artery accesses the scaphoid both dorsally and distally. The ulnar artery in the wrist lies on the TCL giving off a deep palmar branch that communicates with the deep arch prior to forming the superficial palmar arch that lies distal to the deep arch. The digital arteries that run dorsal to the nerves arise from the superficial palmar arch. Intraosseous vascularization is an important consideration because of the risk of spontaneous or traumatic osteonecrosis. The lunate has a volar and dorsal supply in 80% and volar in 20%; there are three configurations e I, X and Y. The scaphoid
Cutaneous nerve supply traversing the carpus and iatropathic injury The cutaneous nerves which cross the wrist are vulnerable to surgical damage e iatropathic injury. Catastrophic neurogenic pain can result from damage to these small nerves and meticulous care must be taken to avoid stretching or cutting these nerves during surgical exposure of the wrist. The dorsal cutaneous branch of the ulnar nerve emerges from the main trunk between 1 and 5 cm proximal to the ulnar styloid.
Figure 8 (a) The palmar blood supply to the wrist. (b) The dorsal blood supply to the wrist.
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receives 80% of its supply from vessels from the radial artery into the dorsal ridge of scaphoid; 20% of the supply is through the volar aspect of scaphoid tubercle.
just distal to Lister’s tubercle. It is vulnerable to accidental division at this point. The marked retinaculum is then divided at its proximal and distal margin. The vertical pillars which separate the compartments (IIeIII, IIIeIV, IVeV) are divided transversely by sharp dissection at their base as they attach to the back of the radius. The retinaculum can now be retracted radialwards (exposing ECRL and ECRB in the second compartment) and ulnarwards (exposing EDC and EIP in the 4th compartment and EDM in the 5th compartment). Distally, beyond the transverseoblique distal margin of the extensor retinaculum, a longitudinal incision is made in the fascia which blends with the retinaculum in line with Lister’s tubercle, allowing the finger extensors to be retracted ulnarwards. The posterior interosseous nerve is identified in the floor of the 4th compartment. 1 cm is routinely excised. The adjacent termination of the posterior interosseous artery should be cauterized. The dorsal capsule is now exposed (Figure 9). With a marker pen, define the direction of the radio-scaphoid, dorsal radio-triquetral and the dorsal inter-carpal ligament. By dividing the capsule along the natural tension lines of these ligaments (Figure 10), as described by Berger the appropriate part of the carpus can be exposed.
FCR approach for distal radius and scaphoid Indications Fracture fixation (e.g. volar locking plate) Osteotomy of the distal radius Open radial styloidectomy (arthroscopic recommended) Scaphoid fixation and grafting Scaphoid osteotomy Procedure A longitudinal skin incision is made over the flexor carpi radialis (FCR) tendon. The deep fascia is incised longitudinally at the radial edge of the FCR which is then retracted ulnarwards. Care is taken to avoid the palmar cutaneous branch of the median nerve which is ulnar to the FCR. The radial artery and superficial radial nerve are gently retracted radially. This exposes the flexor pollicis longus (FPL) tendon which is also exposed radially.
Wrist arthroscopy
Distal radius fracture and osteotomy: the Pronator quadratus (PQ) is elevated from its radial attachment; FPL is also elevated from its radial attachment. This gives complete exposure of the fracture. For an even better view, the brachioradialis muscle is elevated subperiosteally from its attachment.
Indications Diagnostic assessment (e.g. to decide between proximal row carpectomy and four-corner fusion, assessment of interosseous ligamentous instability, assessment of TFCC laxity) Removal of loose bodies Lavage for infection Debridement of synovium Removal of occult wrist ganglion
Scaphoid: the incision is extended distally and radially along the scaphoid tubercle. The superficial branch of the radial artery can be quite large e if so it may be retracted or ligated. The palmar extrinsic ligaments are exposed just distal to PQ. Extension of the wrist helps. The ligament is divided longitudinally along the oblique line of the scaphoid. Elevating 3 mm either side from the radius attachment greatly enhances exposure; meticulously avoid detaching the palmar extrinsic radio-carpal ligaments from the radius as this could lead to wrist destabilization.
Universal dorsal approach to the carpus Indications Scaphoid surgery Four-corner fusion Proximal row carpectomy Vascularisation of lunate Luno-triquetral reconstruction Capitate fracture Brunelli reconstruction Dorsal capsulodesis Wrist replacement Procedure A midline dorsal incision is made, centred over Lister’s tubercle. The skin and subcutaneous fat is elevated from the extensor retinaculum and reflected sideways and held with a self-retaining retractor. The extensor retinaculum is defined and the proximal and distal extent marked with a pen (an oblique line from radialdistal to ulnar-proximal). The retinaculum is then divided along the line of the EPL tendon which has to be found very carefully
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Figure 9 Anatomical capsulotomy. Schematic displaying the radial capsulotomy technique. The incision lines are marked. DRC ¼ dorsal radiocarpal ligament. DIC ¼ dorsal inter-carpal ligament. Lt ¼ Lister’s tubercle.
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Figure 10 Schematic displaying an anatomical capsulotomy with elevation of a radially based flap. A full thickness flap is constructed and radially reflected to expose the radial aspect of the radiocarpal joint and entire midcarpal joint. Carpal stability is achieved by leaving intact half of each capsular ligament.
Figure 11 Wrist arthroscopy portal external landmarks. Schematic of the 10 arthroscopic portals and their relationship to their underlying carpal bones and extensor compartments. 1 ¼ 2R portal. 2 ¼ Scaphotrapeziotrapezoid (STT) portal. 3 ¼ 3e4 portal. 4 ¼ Radial midcarpal (RMC) portal. 5 ¼ 4e5 portal. 6 ¼ Ulnar midcarpal (UMC) portal. 7 ¼ 6R. 8 ¼ Triquetral hamate. 9 ¼ 6U. 10 ¼ DRUJ distal. 11 ¼ DRUJ proximal. EDQ ¼ extensor digiti quinti.
Debridement of central TFCC perforation Capsular shrinkage Capsular release Arthroscopically assisted fracture fixation (scaphoid, radius) Bone removal (styloidectomy, ulnar dome, proximal row carpectomy)
interventions is described, though for those pursuing more detailed knowledge the following list of further reading is recommended. A
Procedure The wrist is suspended by Chinese finger traps over the index and ring fingers. The traps are attached to a suspension frame and distraction is applied. The outline of the distal radius and ulnar head and Lister’s tubercle are marked on the skin. The radio-carpal joint is identified with thumb pressure about 8 mm distal to Lister’s tubercle. The joint is infused with about 8e10 ml of sterile saline, the needle pointing 11 degrees palmarwards to match the angle of the distal radius. An incision 5 mm long is made at the site of needle entry then the tissues are spread gently with a small straight mosquito clip, pushing aside the tendons then puncturing the capsule. A 3.5 mm or 2.9 mm arthroscopic sheath and blunt trochar is then passed into the joint. The trochar is replaced with the arthroscope. Other portals are entered in a similar manner, depending on the planned procedure (Figure 11).
FURTHER READING Berger RA. A method of defining palpable landmarks for the ligamentsplitting dorsal wrist capsulotomy. J Hand Surg Am 2007; 32A: 1291e5. Drake RL, Vogl W, Mitchell AWM. Gray’s anatomy for students. Philadelphia: Churchill Livingstone Publishing, 2005. Gaebler C. Fractures and dislocations of the carpus. In: Bucholz RW, Heckman JD, Court-Brown CM, eds. Rockwood and greens fractures in adults. 6th edn. Philadelphia, USA: Lippincott Williams & Wilkins Publications, 2006; 857e905. Hoppenfeld S, De Boer P, Buckley R. Surgical exposures in orthopaedics: the anatomic approach. Philadelphia: Lippincott Williams & Wilkins Publishing, 2009. Lawler E, Adams BD. Reconstruction for DRUJ instability. Hand 2007; 2: 123e6. Wolfe SW, Hotchkiss RN, Pederson WC, Kozin SH. Greens operative hand surgery, vol. 1. Philadelphia: Elsevier Churchill Livingstone Publishing, 2011.
Summary This article outlines the anatomy of the carpus, particularly that which is relevant to surgical approaches which must pay respect to the blood supply to the carpus, the structural integrity of its ligaments and the nerve supply. Basic exposures for a range of
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(ii) Wrist fractures
These confirmed to the medical profession that these injuries were true fractures, and that most were dorsally displaced. Further clinical descriptions ensued. Dr John Rhea Barton described a shearing-type fracture in 1838, RW Smith of Dublin described a fracture featuring palmar displacement in 1847, yet it would be more than a century before it was realized that fractures of the distal radius could be more than simple extra-articular injuries.1
Douglas A Campbell Tamsin C Wilkinson
Abstract Wrist fractures are seen commonly in everyday orthopaedic practice. This article discusses many of the key areas around recognition, understanding, management and current opinion on fractures involving the distal radius and distal ulna.
Mechanism of injury & biomechanics Most commonly, injuries occur after a simple fall from standing height. Rarely do clinicians take any more detailed history. Yet much information can be gained from asking patients to “describe their fall”. It is natural to pronate the forearm as you fall forwards, and supinate it as you fall backwards. Impact on the pronated forearm is likely to be on the radial side of the wrist, whilst that on the supinated forearm is likely to be on the ulnar side of the wrist. This information stimulates thought as to which other associated structures could be injured during the fall. A fall forwards will focus the examination on the radial structures in the wrist; a fall backwards will draw attention to the ulnar structures. Almost all distal radius fractures (apart from dorsal rim avulsion fractures) can be produced by hyperextension of the wrist.2 Bending forces tend to occur in low-energy falls and typically produce dorsal displacement. Shearing forces disrupt the ligamentous connections of the wrist and produce unstable ‘fracture-dislocations’, whilst axial loading, high-energy injuries compress the articular surface and cause fragments of joint surface to be impacted. Important work, published by Rikli and Regazzoni, on load transfer across the wrist described the existence of three separate structural ‘columns’ within the wrist.3 This ‘3 column concept’ highlights not only how the intact wrist functions, but also provides clear mechanical guidance on how best to reconstruct fractures in this area. The radius has both a ‘radial’ and ‘intermediate’ column, and the ulna represents the third column (Figure 1). The understanding of this concept allows the surgeon
Keywords fracture; outcome; radius; ulna; wrist
History & nomenclature Although Abraham Colles is credited as the father figure and progenitor of distal radius fracture recognition and management, the French physician, JL Petit, first suggested in 1705 that posttraumatic deformity of the wrist may not be due to dislocation (as was commonly thought), but was actually caused by fracture. These ideas were confirmed in the writings of Claude Pouteau (published in 1783 after his death) who stated; “These fractures are most often taken for contusions, luxations incomplete, or for separation of the radius from the ulna at their junction near the wrist” Abraham Colles published his landmark work in 1814 and highlighted the reasons why so much debate had existed about the true nature of the injury when he stated; “.the absence of crepitus and of the other usual symptoms of fracture rendered the diagnosis extremely difficult..” The physical signs of distal radius fracture did not correlate with those of other long bone fractures e most likely due to impaction and relative ‘stability’ of the fragments in the displaced position. The major difficulty for Colles and his contemporaries was that they were describing a fracture 80 years before the discovery of X-rays e which did not occur until 1895. Considering contemporary investigations and imaging, the continuing use of the eponym ‘Colles fracture’ in modern surgical practice can be seen to be potentially inaccurate and perhaps even inappropriate. Dupuytren contributed much to the confirmation that these injuries were fractures, not dislocations, in the publication of the results of his post-mortem dissections in the mid 19th century.
Radial Column Intermediate column
Ulnar Column
Douglas A Campbell ChM FRCS(Ed) FRCS(Orth) FFSEM(UK) Consultant Hand and Wrist Surgeon, Dept of Trauma & Orthopaedic Surgery, Leeds Teaching Hospitals NHS Trust, Great George Street, Leeds, UK. Conflicts of interests: none. Tamsin C Wilkinson FRCS(Tr & Orth) Specialist Registrar, Dept of Trauma & Orthopaedic Surgery, Leeds Teaching Hospitals NHS Trust, Great George Street, Leeds, UK. Conflicts of interests: none.
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Figure 1 The three column concept of Rickli & Regazzoni.
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Extra-articular fractures of the distal radius
to think about ‘rebuilding’ the fragmented wrist in a logical and natural manner and also emphasizes the importance of distal ulnar injuries (see later). Indeed, this concept has also been pivotal in the design of anatomic implants for both the distal radius and ulna.4 The intermediate column is the major load-bearing column of the wrist, confirmed by the dense subchondral bone seen in X-rays of the intact radius. This also explains its involvement in ‘dye-punch’ articular depression injuries. In addition to being a central structural column, the intermediate column also provides the radial component of the distal radioulnar joint (DRUJ) e the sigmoid notch. The bone quality in this distal ulnar corner of the radius is universally good (as a result of its function) and, by virtue of its involvement in both flexion/extension and forearm rotation movements, forms the key area when planning surgical fracture reconstruction. Consequently, surgical reconstruction of the fractured distal radius will concentrate on restoring the integrity and shape of the intermediate column (together with the orientation of the two associated joint surfaces) before restoring the buttressing function of the radial column, and the pivotal function of the distal ulna.
An extra-articular fracture involves neither the radiocarpal nor distal radioulnar joint surfaces. Typically metaphyseal, these injuries classically occur as low-energy bending injuries (Figure 2). Undisplaced fractures should be managed in a simple below elbow cast for 6 weeks, with regular radiological review and cast inspection. Significantly displaced or ‘off-ended’ fractures (Figure 3) demand reduction (preferably closed) and stabilization, usually using Kirschner wires, although open reduction and internal fixation with anatomic palmar plates are gaining popularity e particularly when the wearing of a cast would threaten independence or the pursuit of employment.9 Debate exists as to how best to manage those fractures that are displaced enough to be considered for reduction in some individuals, but not in others, dependent on other co-morbidities and functional demands. There is no clear solution and it may be very difficult, at the outset of treatment, to predict which mildly displaced fractures will cause later functional disturbance. There are a multitude of studies demonstrating significant functional impairment associated with malunion, with evidence of reduced range of motion, grip strength and manual dexterity in malaligned distal radius fractures. However, there are equally valid studies refuting these findings, with little loss of motion or grip strength reported. A recent paper by Forward et al has shown that although patients with malalignment of the distal radius do demonstrate degenerative change radiographically at long-term follow up, this is not related to functional impairment, despite measurable loss of grip strength in these wrists.10 Because there is no consistent message regarding the outcome of malalignment, the concept of an “acceptable reduction” is difficult to define. Certain clear guidelines do exist, however. A recent review of the literature has suggested that restoring radial length to within 2 mm and articular congruency to within 2 mm, improves functional outcome. There is less consensus regarding the importance of restoring dorsal/palmar tilt, with the suggestion that tilt should be restored in the presence of carpal malalignment but can, in some circumstances, be considered acceptable.11 Radial length seems to be a useful predictor of outcome. The short radius will both increase the load borne through the distal ulna and triangular fibrocartilage complex (TFCC) e often by threefold or more e and results in subluxation of the DRUJ. In addition, radial shortening increases the tension in the TFCC, effectively ‘tenting’ it over the distal ulna, with resulting stiffness of the DRUJ and loss of prono-supination (Figure 4).12 This has been shown to correlate with a poor functional outcome. Dorsal tilt will shift the load borne through the radial surface to the dorsal rim, resulting in an increased force per unit area,13 and early degeneration (Figure 5).10 It has also been shown to produce asymmetric increase in TFCC tension and suggests resulting instability.12 DRUJ incongruity also occurs as a result of ‘tilting’ of the sigmoid notch, with resulting loss of prono-supination.14 Radial translation of the distal fragment will result in slackening of the interosseous membrane and potential DRUJ instability without TFCC injury.
Classification Many different authors have produced a multitude of different classification systems e each claiming to describe fracture patterns clearly and reproducibly, and each claiming to help with either treatment planning or outcome prediction. We do not intend to describe each of these in detail in this article, but there are some principles that can be taken from a variety of classification systems. In 1967, Frykman published a classification system that was important in being the first to recognize the involvement (and relevance) of injuries to the distal ulna.5 The Melone system (1993) identified the importance of fragmentation patterns and articular involvement and the AO Comprehensive Classification (1990) described three basic categories of fracture for all bones (Type A e extra articular; Type B e partial articular; Type C e complete articular), which correspond to bending, shear and axial forces. This is a useful categorization, but is difficult to administer reproducibly at the level of sub-types. Fernandez and Jupiter expanded the three basic categories of fracture patterns by adding carpal avulsions and high-energy mixed patterns when they described the Universal System in 1997.6 Further work is now underway assessing the location of fracture lines in relation to the origins of the extrinsic ligaments. Separate classifications of distal ulnar fractures have also been described and are useful in understanding the impact of fracture patterns on both stability and congruity of the DRUJ.7 When considering the classification of a wrist fracture, it is critical to understand the individual personality of each injury. This will include the presence of articular injury, fragment displacement, instability, soft tissue injury, associated injuries, distal ulnar injury and individual patient characteristics. All of these will have an influence on both the management decisions and the outcome. Prognostically, anatomic reduction is still felt to be important, but the necessity for this is questionable in the low-demand population.8
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Insufficiency fractures in the elderly The increasing cohort of patients over 60 years of age in today’s society brings a number of challenges. This group of patients was
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Figure 2 Typical extra-articular bending fracture with associated ulnar styloid fracture.
Figure 3 Displaced extra-articular distal radius fracture.
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Figure 5 Significant dorsal tilt.
complications associated with dorsal plates, such as tendon irritation and loss of flexion due to dorsal scarring. The introduction of angularly stable screws or smooth pins (“locking” screws) into the more dense subchondral bone allows the shape of the implant to be utilized to achieve reduction (Figure 6).17 Contemporary angularly stable implants now “lock” on both sides of the fracture, providing an even more stable solution in osteoporotic bone. The negative impact of surgery in this age group has also diminished as general health has improved, anaesthetic techniques (which are often regional) have become safer, and social support in the postoperative period has become greater. Patients return to independence in a shorter timescale and complications, in the form of continuing disability as a result of malunion, are seen less frequently.9 Whilst this seems to critics to be an aggressive method of management for this age group, protagonists would argue that the clinical results justify a surgical approach.
Figure 4 Significant radial shortening.
previously both chronologically and biologically elderly, but is now maintaining fitness and activity levels for many years after retirement. Not only do this group live independently for longer, they also continue to contribute to society in employment and child-care. Consequently, functionally limiting wrist fractures can change them from contributor to dependent.15 Fracture patterns in this group are usually extra-articular metaphyseal bending fractures, although injuries can involve both the distal radius and ulna. The general fitness and functional demands of an individual will dictate the degree of intervention and the accuracy of reduction that is desirable. Patients with low functional demands will often have a good functional outcome despite significant clinical and radiological deformity, whereas physiologically younger patients with high functional demands at the time of injury are less tolerant of malunion.8 The advent of angularly stable anatomic implants designed for application on the palmar surface of the distal radius has dramatically altered the way these patients can be managed.16 The palmar application of precontoured plates avoids the
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Articular fractures of the distal radius Articular fractures involve the harder subchondral bone and therefore usually result from a greater energy of injury. Consequently, these fractures are seen more frequently in young, active adults. This presents a particular challenge because these
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Figure 6 Indirect reduction and internal fixation of displaced distal radius fracture in osteoporotic bone.
rupture of the extensor tendons.21 Improvements in the surface finish of the implants reduced these complications but did not eradicate them.22 At the same time, developments in implant technology occurred to allow a larger number of fracture patterns to be stabilized with implants applied on the palmar surface of the distal radius. Reduction was achieved by closed, open or indirect methods, and the implant (which must be angularly stable) could be used to stabilize the reduction.23 The potential for irritation of the flexor tendons is significantly less on the palmar surface, as long as the plate is correctly positioned. The ‘watershed line’ is the most volar part of the volar surface of the distal radius and represents the attachment of the volar wrist capsule. The strong volar extrinsic wrist ligaments merge with the capsule and take origin from the radius at this point. If the implant is positioned so that it protrudes distal to the watershed line, the flexor tendons are at risk of irritation and attrition rupture.23 Proximal to the watershed line, the flexor tendons are shielded from the implant by pronator quadratus. Consequently, surgical technique is critical in positioning the implant correctly at the start of fixation. Not all fracture patterns can be stabilized with an implant placed on the volar surface of the distal radius. Whilst the development of anatomic (shaped) implants has undoubtedly increased the spectrum of fracture patterns manageable via this approach, there still remain certain fracture patterns which demand a dorsal approach. The most common type of fracture pattern requiring a dorsal approach is the displaced dorso-ulnar fragment, which forms part of both the radiolunate joint and sigmoid notch. The orientation of the dorsal extrinsic wrist ligaments is such that closed manipulation and reduction by ligamentotaxis is not possible for these fragments. Since they form such a critical part of the radius, accurate and stable reduction is essential. A dorsal approach may be required in such cases. Angular stability is produced in an implant when the threaded head of the screw inserts into a threaded hole in the plate. This
individuals had perfect wrist function and high demands at the time of their injury. They expect to be able to return to their preinjury activities. The frequently high-energy modes of injury (sport, traffic accidents, falls from height, etc) also increase the incidence of associated injuries e which may have a significant impact on the overall outcome. Articular fractures involve the radiocarpal joint, the distal radioulnar joint or both (Figure 7). The functional impact of diminished forearm rotation is greater than diminished flexion/ extension, so great care should be taken in identifying and treating articular fractures of the DRUJ. This area of the distal radius is the keystone of success in managing these injuries.18 Articular fractures are generally considered to recover best if anatomical reduction and stabilization is performed at an early stage to allow functional active range of motion rehabilitation. The historical work of Knirk and Jupiter19 recommended that any steps in the articular surface greater than 2 mm should be reduced as these provoke almost certain early degenerative change. This study, whilst often quoted in the literature over the past 20 years, has now been questioned by the senior author himself and further investigation with modern imaging techniques is required before this question can be authoritatively answered. When planning the surgical reduction and fixation of an articular fracture, a choice of surgical approaches exists. Prior to the introduction of palmar anatomic locking plates in the past decade, the dorsal approach was preferred.20 This was a logical approach, since most fractures featured dorsal comminution and effective bone loss. Direct elevation of these fragments was required, and bone grafting was necessary to prevent early redisplacement. However, implants applied to the dorsal surface of the radius often gave rise to significant complications of tendon irritation and rupture, in view of the close anatomical proximity of these gliding structures to the surface of the metal implant. In one series, 5% of patients required plate removal for tenosynovitis and a further 7% of patients developed attrition
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Figure 7 Displaced intra-articular fracture of distal radius treated by open reduction and internal fixation. (Note: co-existent fracture of ulnar styloid and middle metacarpal).
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demands that the hole for the screw is drilled precisely perpendicular to the threaded plate hole, or the screw will not fit. As a result, the location and position of each screw are fixed relative to the plate. The newest concept of locking implants is to allow a locked screw to be inserted in different trajectories through the same screw hole, so as to aim accurately for smaller bone fragments, rather than have the screw path pre-dictated. This ‘variable angle’ technology still provides angular stability when tightened, but there is a greater choice of screw position within the fragments.9 Great care must be taken when using ‘variable angle’ screws since they can more easily be placed in the joint or into conflict with each other. The recent advances in locking plates have removed the focus from alternative techniques for managing distal radius fractures. However, for those fractures which are too fragmented to be managed by internal fixation, closed reduction and K-wire fixation24 or external fixation remain viable options.25 External fixation can either bridge the radiocarpal joint, with pins located in the shaft of the radius and index metacarpal (Figure 8), or be nonbridging if the size of the distal fragment allows pin placement within it. Bridging fixation relies on ligamentotaxis to reduce fracture fragments, and therefore cannot be used to reduce an
articular fragment with no soft tissue attachment, such as the dye punch fragment in the lunate fossa. Techniques to reduce these fragments using arthroscopic assistance or mini-open reduction with supplementary K-wire fixation or bone grafting have been shown to be effective.26 Such augmentation of the external fixator will also enhance the stability of the fracture, allowing distraction through the frame to be reduced at an earlier stage. Complications associated with external fixation are numerous. In addition to pin tract infection, injury to the superficial branch of the radial nerve, stiffness of the radiocarpal joint and fingers, and Complex Regional Pain Syndrome are well documented, but can be reduced with meticulous surgical technique.27 Intra-articular fractures of the distal radius remain difficult to treat and although recent papers tend to support internal fixation,28 there is a paucity of level 1 evidence to support one technique over another,29,30 provided the articular surface has been adequately reduced.
Imaging Plain radiographs are usually available when patients are first seen in an Emergency Department. Surgeons are also used to requesting CT scans to further understand the fracture pattern and fragment displacement. It is important to look critically at plain radiographs to obtain the maximum amount of information, because these are the only investigations available during surgery and surgeons must remain conversant with the more subtle pieces of information available on these images. A thorough knowledge of radiographic anatomy is essential when reconstructing fractures of the distal radius and ulna. Similarly, a 3D appreciation of the geometry of each of the bones and how they articulate is also necessary. Almost all wrist fractures are easier to understand and visualize when a CT scan is available in addition to plain radiographs. Once the fracture pattern has been fully understood on CT data, it is recommended that the surgeon returns to once more examine the plain radiographs. This will help to assimilate knowledge of the radiographic appearance of common fracture patterns, so that plain radiography (either in the form of plain X-rays or image intensifier views) becomes more meaningful (Figure 9). A lateral plain radiograph of the wrist will not reveal any information other than the condition of the lunate fossa and sigmoid notch of the distal radius. The scaphoid fossa cannot be seen in this view. A 20 inclined lateral will, however, provide this information and should form a routine part of preoperative screening. Similarly, a PA plain radiograph does not provide any information on whether or not subchondral screws have penetrated the joint surface. A 15 inclined PA view will be parallel to the joint surface and give accurate information on screw penetration and joint congruity.31 Other more sophisticated imaging, such as MR arthrography, is extremely useful when assessing associated injuries but will provide little assistance in managing the skeletal elements of the injury.
Distal ulnar fractures The distal ulna forms the third column of the wrist. Fractures of this bone have, until recently, been largely ignored. Fractures
Figure 8 Comminuted articular fracture treated by non-distracted external fixation with supplementary K-wire.
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Figure 9 Lateral x-ray and CT scan demonstrating ‘dye punch’ fracture.
of the ulnar styloid are commonly seen, but their relevance is poorly understood. The distal ulna can fracture in several different patterns; simple neck, comminuted head, simple neck þ ulnar styloid and multifragmentary extending into the distal shaft.7 The importance of distal ulnar fractures is a consequence of their contribution to both stability and congruity of the DRUJ. Not all distal ulnar fractures require active treatment. Indeed, only the minority of these fractures demand intervention. To identify which fractures require treatment, it is crucial to understand how the DRUJ is constructed and how it functions. Stability will be threatened by either displaced fractures of the articular surface, or avulsion of the stabilizing structures (most frequently the foveal attachment of the TFCC). Under load, the styloid attachment of the TFCC contributes little to stability, whilst the foveal attachment contributes greatly to DRUJ stability. This explains why fractures of the tip of the styloid are so innocuous, whilst fractures at the base are significant contributors to instability.32 It is mandatory to assess the stability of the DRUJ after performing any fixation of a distal radius fracture. Stability is assessed by firmly grasping the distal radius in one hand and, with the patient’s elbow flexed to at least 90 and in neutral forearm rotation, grasp the distal ulna in the other examining hand. Passive AP glide can then be compared to the opposite, uninjured hand, which will give information about the stability of the DRUJ. This clinical test can be made more sensitive by performing distal ulnar AP glide with the wrist in ulnar deviation, then radial deviation. The AP glide should tighten when the wrist is in radial deviation.
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Joint congruity can be assessed by plain radiography and by CT scan. Accurate reduction and stabilization is necessary in displaced injuries to restore the ulna as both a pivot for forearm rotation and a stable buttress for contact with the sigmoid notch of the distal radius. Fractures involving both distal radius and ulna are often misunderstood and managed as a radial fracture alone. These are forearm fractures that happen to be near the wrist, and should be managed in the same way as a diaphyseal injury of both bones (Figure 10).7 When distal ulnar fractures are stabilized by secure internal fixation, early rehabilitation can involve active and passive forearm rotation movements. This reduces the risk of scarring of the interosseous ligament and consequent permanent restriction of movement. Ulnar styloid fractures are frequently seen, but rarely require active treatment. The significance of the attachment of the deep fibres of the TFCC in the ulnar fovea means that oblique basistyloid fractures are the most likely type of ulnar styloid fracture to require active stabilization. Clinical examination of DRUJ stability, as described above, will guide the surgeon.
Incidence & identification of associated injuries Arthroscopic studies have proved that associated injuries occur frequently. A study by Richards et al identified TFCC tears in 53% of intra-articular fractures, scapholunate ligament tears in 21.5% of intra-articular fractures and lunatotriquetral ligament injuries in 6.7% of intra-articular fractures and 13.3% of extra-
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Figure 11 Displaced radial styloid fragment, incompletely reduced with coexistent scapholunate diastasis.
a separate radial styloid fragment e particularly if displaced e will temporarily leave the scaphoid unsupported by the scaphoid fossa, whilst the lunate remains stable within the radiolunate joint (Figure 11). The scapholunate ligament is frequently injured in this fracture pattern and can be readily recognized if sought. Alteration in carpal radiographic anatomy will raise suspicion of an intrinsic ligament injury. Fracture around the distal ulna will highlight the potential disruption in integrity of the DRUJ stabilizing structures. Clinical examination will determine stability. It remains unusual, however, to identify an associated injury in the acute setting. They are usually discovered in the weeks after injury when rehabilitation is unexpectedly poor, or physical signs reveal themselves. Clinicians treating wrist fractures must always consider possible associated injuries during each consultation until rehabilitation is complete.
Figure 10 Fractures of distal radius and ulna treated by open reduction and internal fixation.
articular fractures.33 Yet function-limiting problems are rarely seen in the long-term in untreated cases. The difficulty therefore lies in the identification of such injuries and the decision-making around which ones demand treatment. A dorsal, open approach, when performing internal fixation, will allow direct inspection of the intrinsic ligaments, but these approaches are less frequently performed with modern implants. Consequently, the clinician must have a high index of suspicion when assessing wrist fractures, and look for any clue or suggestion of associated injury. Certain fracture patterns give rise to a greater risk of certain associated injuries. For example,
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Children’s fractures Fractures of the distal radius are common in childhood, and almost universally result in a normal functional outcome. The majority of fractures are buckle or torus fractures (Figure 12), which can be adequately treated by splinting for 3 weeks, the splint being removed by the parents.34 Rarely do these fractures require surgical intervention, due to the inherent stability of buckle fractures and the large remodelling potential, although closed manipulation is indicated where unacceptable alignment of greater than 20 of angulation in the flexion/extension plane
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due to the proximity of the distal radial physis, will correct if sufficient time for growth remains. Malunion of less than 20 will take up to 2 years to correct, so this must be borne in mind when treating older children. Care must be taken to identify a Galeazzi fracture-dislocation, since these injuries demand early reduction and stabilization. Growth will correct the radial deformity in time in many cases, but DRUJ biomechanics may suffer irreversible damage before this correction is complete. Growth arrest is uncommon, complicating approximately 4% of all physeal injuries of the distal radius, but up to 50% of displaced physeal fractures of the ulna.35 It may be partial or complete. Partial arrest will result in progressive deformity over time, and the timing of any surgical intervention needs careful thought. In rare cases, repeat osteotomy is required as growth (and progressive deformity) continues after the first procedure (Figure 13).
Complications Complications after wrist fracture can be classified into: Early (occurring before the normal fracture healing time) Medium term (occurring after normal fracture healing time but before rehabilitation is complete) Late (occurring after healing & rehabilitation) Early complications include - median nerve injury (disturbance from the time of injury) - carpal tunnel syndrome (caused by oedema in the first hours after injury) - redisplacement (after manipulation or surgical treatment) - associated injury
Figure 12 Typical buckle fracture in distal radius of 10 year old child.
or 10 of radial/ulnar deviation exists. The majority of fractures involve the distal radial metaphysis, but when the physis is involved, care must be taken not to further injure the growth plate by repeated forceful manipulation or by introducing blunt or threaded K-wire. Younger children heal quickly and also have a significant capacity for remodelling. Malunion is common, but
Figure 13 Complete physeal arrest treated by radial lengthening and ulnar shortening osteotomies.
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Medium term complications include - delayed or non union (rare except in both bone or open fractures) - stiffness and loss of motion (wrist and/or digits) - complex regional pain syndrome (type I) e CRPS I - ulnar wrist pain Long-term complications include - malunion - osteoarthritis - permanent loss of motion - cosmetic deformity Each specific complication has its own specific management. The awareness of potential complications is the best tool for avoiding them.
and distal radioulnar joints optimizes function, whilst the appreciation of the functional importance of the distal ulna and its soft tissue attachments should avoid undertreatment when these structures are involved in the injury. A
REFERENCES 1 Imrie M, Yao J. Distal radius fractures: a historical perspective. Fractures and injuries of the distal radius and carpus. Elsevier, 2009. pp. 1e10. 2 Pechlaner S, Kathrein A, Gabl M, et al. Distal radius fractures and concomitant lesions. Experimental studies concerning the pathomechanism. Handchir Mikrochir Plast Chir 2002; 34: 150e7. 3 Rickli DA, Honigmann P, Babst R, Cristalli A, Morlock MM, Mittlmeier T. Intra-articular pressure measurements in the radioulnocarpal joint using a novel sensor: in vitro and in vivo results. J Hand Surg Am 2007; 32A: 67e75. 4 Rikli DA, Regazzoni P. Fractures of the distal end of the radius treated by internal fixation and early function. A preliminary report of 20 cases. J Bone Joint Surg Br 1996; 78-B: 588e92. 5 Frykman G. Fractures of the distal radius, including sequelae e shoulder-hand-finger syndrome, disturbance of the distal radioulnar joint and impairment of nerve function: a clinical and experimental study. Acta Orthop Scand 1967;(suppl 108): 1e155. 6 Jupiter JB, Fernandez FL. Comparative classification for fractures of the distal end of the radius. J Hand Surg Am 1997; 22: 563e71. 7 Ring D, McCarty LP, Campbell D, Jupiter JB. Condylar blade plate fixation of unstable fractures of the distal ulna associated with fracture of the distal radius. J Hand Surg Am 2004; 29: 103e9. 8 Young BT, Rayan GM. Outcome following nonoperative treatment of displaced distal radius fractures in low-demand patients older than 60 years. J Hand Surg Am 2000; 25: 19e28. 9 Downing ND, Karantana A. A revolution in the management of fractures of the distal radius? J Bone Joint Surg Br 2008; 90-B: 1271e5. 10 Forward DP, Davis TRC, Sithole JS. Do young patients with malunited fractures of the distal radius inevitably develop symptomatic posttraumatic osteoarthritis? J Bone Joint Surg Br 2008; 90-B: 629e37. 11 Ng CY, McQueen MM. What are the radiological predictors of functional outcome following fractures of the distal radius? J Bone Joint Surg Br 2011; 93-B: 145e50. 12 Adams B. Effects of radial deformity on distal radioulnar joint mechanics. J Hand Surg Am 1993; 18A: 492e8. 13 Short WH, Palmer AK, Werner FW, Murphy DJ. A biomechanical study of distal radial fractures. J Hand Surg Am 1987; 12: 529e43. 14 Kihara H, Palmer AK, Werner FW, Short WH, Fortino MD. The effect of dorsally angulated distal radius fractures on distal radioulnar joint congruency and forearm rotation. J Hand Surg Am 1996; 21: 40e7. 15 Gehrmann SV, Windolf JW, Kaufmann RA. Distal radius fracture management in elderly patients: a literature review. J Hand Surg Am 2008; 33A: 421e9. 16 Larson AN, Rizzo M. Locking plate technology and its applications in upper extremity fracture care. Hand Clin 2007; 23: 269e78. 17 Yoshiro K. Condylar stabilizing technique with AO/ASIF distal radius plate for colles’ fracture associated with osteoporosis. Tech Hand Up Extrem Surg 2002; 6: 205e8. 18 Stoffelen D, De Smet L, Broos P. The importance of the distal radioulnar joint in distal radial fractures. J Hand Surg Br 1998; 23-B: 507e11.
Outcome Outcome is difficult to measure after wrist fractures. The same radiographic fracture pattern treated in the same way by the same surgeon will often produce widely different results in different individuals. Various objective measurements of functional outcome have been described, from the much-used Gartland & Werley demerit scoring system (1951) to more modern assessments of global upper limb function (DASH) and general wellbeing (SF-36). None of these are reliable enough to critically appraise comparative management methods. The Cochrane database has clearly stated that insufficient evidence exists in even the most scientifically rigorous clinical studies, to ascertain the ‘best’ treatment methods for wrist fractures.29,30 As a result, we are condemned to continue managing these injuries with our favourite techniques (or, alternatively, avoiding our least favourite techniques) insecure in our knowledge that we are providing the ‘best’ treatment. There are many excellent pieces of scientific and clinical evidence available when making decisions about fracture management around the wrist, but the variability of our patients (and e to a degree e the variability of our clinicians) makes objective comparison impossible. There remain some recommendations about how best to avoid a poor outcome, although even these have exceptions that are regularly quoted by those with a different view. These recommendations would include: Correct the radiographic anatomy Identify and manage associated injuries Consider reduction of articular steps greater than 1 mm Control oedema and pain at an early stage Consider the ulna in all wrist fractures Be aware of risk factors for redisplacement B osteoporosis B comminution B tenuous stabilization
Conclusion Fractures of the distal radius are common, and their assessment and management are often taken for granted. However, an appreciation of the structure and function of the wrist and the application of sound biomechanical principles allows a reasoned approach to decision-making and can facilitate treatment choices, both operative and non-operative. Articular reconstruction of the radiocarpal
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19 Knirk JL, Jupiter J. Intra-articular fractures of the distal end of the radius in young adults. J Bone Joint Surg Am 1986; 68-A: 657e9. 20 Campbell DA. Open reduction and internal fixation of intra-articular and unstable fractures of the distal radius using the AO distal radius plate. J Hand Surg Br 2000; 25-B: 528e34. 21 Jakob M, Rikli DA, Regazzoni P. Fractures of the distal radius treated by internal fixation and early function. A prospective study of 73 consecutive patients. J Bone Joint Surg Br 2000; 82-B: 340e4. 22 Orbay JL, Fernandez DL. Volar fixation for dorsally displaced fractures of the distal radius: a preliminary report. J Hand Surg Am 2002; 27A: 205e15. 23 Orbay JL, Touhami A. Current concepts in volar fixed-angle of unstable distal radius fractures. Clin Orthop 2006; 445: 58e67. 24 Kreder HJ, Hanel DP, Agel J, McKee M, Schemitsch EH, Trumble TE, et al. Indirect reduction and percutaneous fixation versus open reduction and internal fixation for displaced intra-articular fractures of the distal radius. J Bone Joint Surg Br 2005; 87-B: 829e36. 25 Kapoor H, Agarwal A, Dhaon BK. Displaced intra-articular fractures of distal radius: a comparative evaluation of results following closed reduction, external fixation and open reduction with internal fixation. Injury 2000; 31: 75e9. 26 Seitz WH, Froimson AI, Leb R, Shapiro JD. Augmented external fixation of unstable distal radius fractures. J Hand Surg Am 1991; 16A: 1010e6. 27 Sanders RA, Keppel FL, Waldrop JI. External fixation of distal radial fractures: results and complications. J Hand Surg Am 1991; 16A: 385e91.
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28 Wright TW, Horodyski M, Smith DW. Functional outcome of unstable distal radius fractures: ORIF with a volar fixed angle tine plate versus external fixation. J Hand Surg Am 2005; 30: 289e99. 29 Handoll HHG, Vaghela MV, Madhok R. Percutaneous pinning for treating distal radial fractures in adults. Cochrane Database Syst Rev 2011. Issue 3. Art. No.:CD006080. doi:10.1002/14651858.CD006080. Pub2. 30 Handoll HHG, Huntley JS, Madhok R. Different methods of external fixation for treating distal radial fractures in adults. Cochrane Database Syst Rev 2008. Issue 1. Art. No.:CD006522. doi:10.1002/ 14651858.CD00652.Pub2. 31 Boyer MI, Korcek KJ, Gelberman RH, Gilula LA, Ditsios K, Evanoff BA. Anatomic tilt X-rays of the distal radius: an ex vivo analysis of surgical fixation. J Hand Surg Am 2004; 29: 116e22. 32 Haugstvedt JR, Berger RA, Nakamura T, Neale P, Berglund L, An KN. Relative contributions of the ulnar attachments of the triangular fibrocartilage complex to the dynamic stability of the distal radioulnar joint. J Hand Surg Am 2006; 31: 445e51. 33 Richards RS, Bennett JD, Roth JH, Milne K. Arthroscopic diagnosis of intra-articular soft tissue injuries associated with distal radial fractures. J Hand Surg Am 1997; 22: 772e6. 34 Davidson JS, Brown DJ, Barnes SN, Bruce CE. Simple treatment for torus fractures of the distal radius. J Bone Joint Surg Br 2001; 83B: 1173e5. 35 Cannata G, De Maio F, Mancini F, Ippolito E. Physeal fractures of the distal radius and ulna: long term prognosis. J Orthop Trauma 2003; 17: 172e9.
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(iii) Injuries of the carpus
necessitate work-place adaptations, modifications, or even a career change. The mechanism of injury is normally an axial load, with the position of the wrist at the time of injury being the main determinant of which carpal bone fractures and in what configuration. A direct blow, crush, or penetrating injury can obviously have many resultant patterns of injury. A meticulous history of the mechanism of injury is essential, along with careful clinical examination, looking in particular for areas of swelling, bruising, or deformity. Methodical palpation for tenderness, crepitus, and instability should be performed as the signs can be quite subtle. When examining the carpus it is important to accurately palpate the wrist for tender areas with the examiners fingertip or the end of a rubber-tipped pencil. Systematic examination of this nature may reveal specific tenderness over the carpal bones, the scapholunate ligament or other signs which require care and attention to detect. This avoids unhelpful referrals or requests for further imaging which provide only a vague indication such as “wrist pain”, giving few clues to guide another clinician or reporting radiologist. Comparison to the other wrist is useful once a sore area is identified, as there are some areas of the wrist in some patients, which are inherently sensitive. Specific clinical tests for bony and soft tissue injuries of the wrist include 3-point scaphoid palpation, Kirk-Watson’s test, scapholunate ballottement, lunotriquetral ballottement, pisiform shift test, and carpal pseudo-stability. Palpation of the scaphoid from three directions and finding tenderness has been shown to pick up scaphoid injuries in a very high proportion of patients.4 The scaphoid should be palpated over its body in the anatomical snuffbox, and over its distal tubercle on the volar aspect of the wrist at the level of the distal wrist crease, just radial to the tendon of flexor carpi radialis (although occasionally the most prominent bony mass can be the ridge of the trapezium). Finally axial load should be applied to the scaphoid by the examiner using the thumb and index finger of the one hand to apply longitudinal compression to the thumb metacarpal, which in turn compresses the trapezium onto the distal pole of the scaphoid, while stabilizing the wrist with the other hand. It is essential to record the neurovascular status of the injured limb prior to any treatment. Serial examinations are also necessary to assess deterioration or impending compartment syndrome of the arm or hand. The general trauma surgeon may not always wish to address the definitive treatment for complex ligament injuries or subtle carpal fractures acutely. However, reduction of dislocations, debridement of open wounds and decompression of impending or established compartment syndrome should be within the remit of any on-call surgeon. Wrist injuries, and especially perilunate injuries, have a high risk of “acute carpal tunnel compartment syndrome”, which requires urgent decompression to prevent permanent median nerve damage. The hand is comprised of 10 myofascial compartments. These are: the four dorsal interosseous, three volar interosseous, thenar, hypothenar, and adductor pollicis compartments. The technique for complete release of the myofascial compartments involves two dorsal, one radial border, and one ulnar border incision. Finally, a carpal tunnel release should not be forgotten in order to ensure median nerve viability. The two dorsal
Helen Whalley Ian McNab
Abstract Fractures of the carpus account for one-fifth of all hand fractures, although if scaphoid fractures are excluded, the remaining seven carpal bones amount to only 1.1% of all such fractures. Rarity renders these injuries a diagnostic challenge as, within the practice of a general orthopaedic surgeon, they are infrequently encountered and can be difficult to visualize on standard radiographs due to the complex three-dimensional nature of their anatomy and articulation. Cross-sectional imaging of all wrist injuries is not necessary or economically feasible and hence clues to the patient’s mechanism of injury, clinical examination, and plain radiographs must be sought in order that appropriate escalations of injury management ensue. Injuries to the carpus tend to occur in young active people of working age and hence missing or inadequately treating these fractures has potentially catastrophic implications to the patient, and to society as a whole. Prompt diagnosis and treatment may lead to faster recovery and may minimize long-term sequelae. This article seeks to give simple guidance to help the general orthopaedic surgeon to recognize, investigate and treat soft tissue and bony injuries relating to the carpal bones.
Keywords carpus; dislocation; fractures; hand; wrist
Introduction The order of frequency in which the carpal bones are fractured has been extensively researched. Undisputedly the scaphoid is the most commonly injured carpal bone, accounting for approximately 70% of carpal fractures, with the triquetrum and trapezium following in second and third places, accounting for a further 15% and 3% of carpal fractures respectively.1 The lunate, hamate, capitate, and pisiform account for approximately 1% each and the trapezoid is the least commonly fractured at 0.2% of carpal fractures.2 Carpal fractures tend to occur in young males who are engaging in sports or manual work and who have high functional demands on their hands in their lives ahead.3 The patient may be the sole breadwinner for their family and hence time spent unable to work due to treatment in a plaster, or recovering from an operation, may be costly. Inadequately treated or missed injuries requiring reconstruction or salvage procedures could result in further time off work, inability to drive, or may
Helen Whalley FRCS (Orth) Hand Fellow, Nuffield Orthopaedic Centre, Oxford, UK. Conflict of interest: none declared. Ian McNab FRCS (Orth) Consultant Hand Surgeon, Nuffield Orthopaedic Centre, Oxford, UK. Conflict of interest: none declared.
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myofascial incisions are aligned respectively over the second and fourth metacarpals, and are used to access the dorsal and palmar interossei. The second dorsal metacarpal incision is utilized to access the deep adductor pollicis compartment. Longitudinal incisions along the thumb and little finger metacarpal borders, where the transition of palmar to dorsal skin occurs, are used to access the thenar and hypothenar muscular compartments respectively. A standard carpal tunnel release in line with the long finger/ring finger interspace must be performed in all cases of suspected or confirmed compartment syndrome to relieve pressure on the median nerve (Figure 1). If the patient is to be appropriately treated non-operatively, or if there is a delay to theatre, adequate provision of analgesia, appropriate splinting and elevation of the hand must be instigated. In the first few hours after an acute injury, accurate palpation or instability testing of the wrist may be impaired by pain, so reexamination of the wrist after analgesia, temporary splinting and elevation maybe a useful tool (Summary Box 1).
Compartment syndrome of the hand C
C
Ten myofascial compartments þ carpal tunnel need to be released Five incisions needed: B Two dorsal over the 2nd and 4th metacarpals - Access the four dorsal interosseous compartments - Access three volar interosseous compartments - Access adductor pollicis compartment via index/ long interspace B
Two palm border incisions - Radial border of thumb metacarpal for thenar compartment - Ulna border of little finger metacarpal for hypothenar compartment
B
Carpal tunnel release - Standard incision to release median nerve
Imaging The distal radius can be adequately imaged with simple PA and lateral radiographs. However, given the complex three-dimensional structure of the carpus, further views may be needed for a complete evaluation. The standard “scaphoid views” comprise a PA, a true lateral, a “radial oblique” and a PA view with the wrist in ulna deviation. The radial oblique view is taken in pronation with the radial side of the wrist 30 degrees elevated off the table and is the only view which adequately shows the trapeziotrapezoidal joint and also can be helpful to evaluate the waist of the scaphoid. Fractures are difficult to visualize on radiographs unless the X-ray beam is aligned with the plane of the fracture. In the scaphoid PA ulna deviation view the beam is directed 20e30 degrees cephalad so that it is perpendicular to the naturally flexed axis of the bone so is aligned with the usual plane of the fracture. The view also elongates the scaphoid, helping to reveal subtle fractures.5 An ideal standard PA view should profile the extensor carpi ulnaris tendon groove at, or just radial to, the base of the ulnar styloid.6
Summary Box 1
In the PA view close attention should be paid to Gilula’s lines5 (Figure 2). Disruption of these lines can reveal carpal disruption of a bony or ligamentous nature and may hence indicate the need for further investigation or imaging. Disruption of the scapholunate ligament may be revealed by inspection of the scapholunate interval. This should approximate the other intercarpal spaces if normal, but widening, also known
Figure 1 Axial view showing incisions for release of compartment syndrome of the hand.
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Figure 2 X-ray with Gilula’s lines marked.
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as the “Terry Thomas Sign” due to the gap between this actor’s front teeth, may be evident if the ligament is torn. A PA clenched fist view can accentuate this gap and comparison films of the uninjured wrist are very helpful to ascertain the normal appearances for an individual patient. The “Signet ring sign” may also be apparent in the PA view due to scapholunate ligament disruption. This occurs because of hyperflexion of the scaphoid if the restraint of the ligament is compromised. The distal tubercle of the scaphoid is seen as an axial view, hence the cortices form a ring shape in profile. The lateral view of the wrist should reveal an overlapping longitudinal line down the axis of the radius and ulna, and then onwards through the lunate, capitate and then the superimposed lateral views of the metacarpals (Figure 3). Scaphopisocapitate orientation defines the true lateral view and this should show the palmar surface of the pisiform situated in the central third of the interval between the palmar cortices of the distal scaphoid pole and the capitate head7 (Figure 4). CT scanning can be useful in defining difficult or occult fractures. 1 mm interval “cuts” are required to fully assess the carpus, and sagittal oblique slices along the long axis of the scaphoid (from the base of the thumb to Lister’s tubercle) are ideal for picking up subtle breaks in the cortices or trabeculae in this bone.8 In the non-acute setting it is also useful for assessing union, malunion, and humpback deformity in scaphoid fracture.
Figure 4 A true lateral X-ray showing the volar cortex of the pisiform lying in the central third of the interval between the volar cortices of the capitate and distal pole of scaphoid.
MRI scanning should include images in the transverse and coronal planes. Sequences with fat suppression in order to show fluid and oedema are helpful. MRI is more sensitive than CT at detecting occult scaphoid injury in the acute stages and is able to reveal subtle bone bruising, trabecular microfracture and ligamentous injuries. It can be augmented with arthrography, particularly for identification of scapholunate ligament or TFCC ligament tears. Again, fine sections are needed to diagnose subtle injuries.9,10 MRI scans (augmented with intravenous gadolinium enhancement) are particularly useful for looking at vascularity, particularly of the proximal pole in scaphoid non-union, and for evidence and staging of Kienbock’s disease or other osteonecroses. Radionucleotide scanning is sensitive but not specific in hand and wrist injury and has largely been superseded by fine slice CT or MRI. In the very acute phase false negative results can occur, before fluid has had chance to accumulate. Ultrasonography is rarely indicated, unless one is evaluating for potential soft tissue damage including chronic attritional problems of tendons or synovitis. Following the practice of repeated evaluation in general trauma, when a wrist injury is clinically or radiologically diagnosed, one must persist in systematically examining the patient and the X-rays for further injuries. Carpal fractures are
Figure 3 A true lateral X-ray showing the radius lining up with the lunate, capitate, and metacarpals.
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commonly associated with distal radius fractures, ulna fractures, more proximal injuries (such as radial head fractures), and perilunate injuries.11 Subtle fractures of the scaphoid waist, radial styloid or ulna styloid can suggest lesser or greater arc injuries to ligamentous or bony structures around the lunate. Mayfield described the progressive circumferential way in which injury forces could propagate around this area which will be described later. The general management plan for the carpal fractures is presented in Summary Box 2.
should be placed in a below elbow cast with the thumb free. The only indication for including the thumb is for patient comfort and does not affect rate or ability of the fracture to heal.14 The cast should remain for 8 weeks at which point clinical examination and repeat X-rays out of the cast should be taken. It is very problematic assessing healing on the plain films, as the scaphoid is almost entirely covered in articular cartilage and a periosteal reaction does not occur. Dias addressed this conundrum in his paper in 2001.15 If the patient is still tender at 8 weeks, a further 4 weeks in a cast should be initiated. CT scanning at 3e6 months should occur if plain films are inconclusive or there is radiological or clinical suspicion that the fracture has not united. Patients should have final X-rays 6 months post-injury to ensure bony union. Undisplaced fractures can be treated operatively with percutaneous fixation with a headless compression screw, although little benefit, apart from time saved in a cast, has been shown with this line of treatment.16e19 Proximal pole fractures should be approached dorsally, undisplaced waist fractures from the volar or dorsal side, and distal fractures from the volar side. Open fixation for displaced fractures should usually be approached from the same side as the percutaneous fixation would be performed, whilst taking into consideration planning for other simultaneous procedures.
Specific injuries Scaphoid Scaphoid fractures are by far the most commonly encountered carpal fracture. They usually occur as a result a wrist hyperextension injury during a fall onto outstretched hand when participating in sports, a fall from a height or at speed, although 2% have been reported to be secondary to flexion-type injuries. Imaging of the scaphoid should be initially performed using the four-view series described above. Identification of a fracture on these views can still be difficult, and in the presence of pain over the scaphoid, immobilization in a cast for 2 weeks and then repeat X-rays are common practice. If the patient remains tender at 2 weeks and the plain radiographs are inconclusive, few surgeons would argue against the need for further imaging. Early CT or MRI scanning can avoid inconvenient and unnecessary immobilization but clearly in some hospitals there is inadequate facility, availability, or funding for this line of management.12 Thought should be given in the history taking and thorough careful examination of the radiographs for evidence of non-acute scaphoid fracture, non-union, or existing avascular necrosis.3 Fractures most commonly occur at the scaphoid waist, but may occur in the proximal or distal pole which includes the tubercle. As with all fractures, they can either be undisplaced, displaced, simple, or multifragmentory. A detailed review on assessing and managing acute scaphoid fractures and non-union was published in an earlier edition of Orthopaedics and Trauma.13 In summary, patients with displaced fractures or proximal pole fractures should be treated operatively, and all other fractures
Triquetrum The most common fracture pattern is a dorsal cortical pattern, which occurs either due to dorsal extrinsic ligament avulsion if the wrist is volar flexed or, if the wrist is extended, impaction of the ulnar styloid or proximal hamate on the triquetrum. A triquetrum body fracture is less common and tends to occur in a transverse manner in association with a perilunate fracturedislocation, and hence careful inspection of the radiographs and a low threshold for further imaging is necessary. The radial oblique radiograph is most useful for identifying triquetrum fractures, as the other carpal bones are not overlapping its cortices in this projection. The management of triquetrum fractures can be simplified into; cast treatment for extra-articular fractures and undisplaced fractures, reduction and fixation with wires or small screws for displaced fractures, and for those fractures which are associated with perilunate fracture-dislocations operative treatment is directed primarily at repair of the ligament injury and restoration of stability of the carpus.
General principles of carpal fracture management C
Immediate treatment: B Reduction of dislocations B Decompression of compartment syndrome B Elevate and splint
C
Definitive early treatment: B Cast for extra-articular and minimally displaced fractures B Anatomical reduction and fixation for - Displaced fractures - Intra-articular fractures - Ligament disruptions open ligament direct repair
Trapezium The mechanism of injury is usually high energy and not only should detailed assessment be performed for fractures of the distal radius, other carpus, and first metacarpal, but minimally displaced fractures should be followed up carefully to assess for late displacement. Three main trapezial fracture patterns occur; body, marginal, and volar ridge. The mechanism for a body fracture is transverse loading of the adducted thumb metacarpal which is driven into the trapezium. This tends to result in an intra-articular longitudinal fracture pattern. The transverse carpal ligament can cause an avulsion of the volar ridge, and other ligamentous attachments including the volar beak ligament can cause small marginal fractures which are easy to miss.
Summary Box 2
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A carpal tunnel view can help identify trapezial ridge fractures and the pronation oblique view helps to isolate the profile of the trapezium. Displaced intra-articular fractures benefit from open reduction via a volar approach and internal fixation with wires or compression screws. The surgeon must remember that the radial artery runs between the dorsal radial and dorsal ulna ridges of the trapezium, and care must be taken to protect this vessel intraoperatively. Trapezium ridge fractures are also easily missed and if a painful non-union occurs, excision of the fragments can relieve symptoms from the fracture site but the patient can be left with a painful scar. Trapezium fractures can be associated with acute or chronic carpal tunnel syndrome, tendonitis, and FCR rupture.
entity. Minimally displaced, isolated fractures are treated with cast immobilization. The capitate has a tendency to delayed-union, non-union and carpal collapse due to its tenuous blood supply and hence displaced fractures are best treated with open reduction and internal fixation, along with repair of associated injuries, via a dorsal approach between the third and fourth extensor compartments. Complex injuries of a perilunate nature should be addressed with concomitant repair of ligament ruptures and carpal fractures. Stiffness and pain secondary to non-union and carpal collapse are not infrequent. Hamate The hook of the hamate is prone to fracture in golfers due to an impact to the palm or fall onto outstretched hand. Tenderness is felt over the tip of the hook in the hypothenar eminence although comparison with the contralateral side is useful as this area can be unpleasant to palpate for many patients. Irritation of the ulna nerve as it goes through Guyon’s canal can result in motor or sensory symptoms, and the nearby FDS and FDP to the little and ring fingers can make flexion of these digits painful. Indeed, rupture can occur in the chronic setting.20 The hook can be best visualized on plain radiography using a carpal tunnel view, although CT scanning gives the most reliable depiction of anatomy as adequate extension of the wrist for the carpal tunnel view may be painful for the patient if acutely injured. A fracture may be imitated by an os hamulus proprius, an unfused ossification centre, but this is usually much larger than the normal hook of hamate and is seen to be well corticated. Early immobilization in a short arm plaster results in healing in the majority of cases. Symptomatic non-unions can be successfully treated by careful excision, with acute fixation having little advantage. However fixation can be performed through a volar approach centred over the hook, with extreme care to protect the ulnar nerve. Fractures of the body of the hamate are rare but again the principle of reducing and fixing displaced or intra-articular fractures with wires, compression screws or small plates, should be employed. A dorsal approach to the hamate and ulna side CMC joints is usually employed. Stability of the fourth and fifth CMC joints should be ascertained and addressed if compromised, usually with closed reduction and wiring to the adjacent stable metacarpals, and wiring of the metacarpals to the articulating carpal bones. Cast immobilization follows and the wires are retained for 4e6 weeks.21 Again, care should be exercised in order to protect the ulnar nerve branches on the volar and dorsal side of the bone during the approach or when inserting metalwork.
Lunate Of all the carpal bones, the lunate has the largest area of cartilage cover compared to its size. The proximal lunate has no soft tissue attachment and a very tenuous blood supply, rendering it vulnerable to acute and chronic trauma. It is important to remember an incidental finding of Kienbock’s disease before diagnosing an acute lunate fracture. Sclerosis or subchondral cysts may exist at the lunate’s proximal ulna border indicative of ulna abutment and this must not be confused with an acute injury. Axial load is the common mechanism of injury and the lateral radiograph should be inspected to assess for subluxation of the capitate which may indicate a loss in bony congruity of the distal surface of the lunate. Careful examination of the lateral radiograph may reveal a break in continuity of the volar or dorsal cortex which may suggest a distal volar or dorsal lunate fracture. Undisplaced fractures should be treated with cast immobilization for 4e6 weeks. Displaced fractures or fractures leading to subluxation should ideally be fixed with compression screws or with wires if the fragments are too small. Due to the bone’s tenuous blood supply, volar fractures should be reduced and fixed because the most reliable nutrient arteries enter on the volar side and non-union may ensue if they are not anatomically reduced. Volar fractures should be approached via an extended carpal tunnel incision and dorsal or body fractures through a dorsal approach with care to preserve the blood supply and repair to ligamentous detachments. Splinting in a short arm cast should be instigated post-operatively for a period of 6e8 weeks. Capitate The capitate is the largest of the carpal bones and is well protected by adjacent carpal and metacarpal bones. Transverse fractures of the capitate are the most common fracture pattern and these commonly accompany perilunate fracture-dislocation injuries. A high energy fall onto outstretched hand is the usual mechanism of fracture. If the scaphoid has already fractured, the wrist continues to dorsiflex, and the neck of the capitate is impacted upon the dorsal rim of the distal radius and hence fractures. The distal end of the proximal fragment can be pushed volarly as the wrist returns to its resting position, resulting in it having been rotated through 180 degrees, the so-called “scaphocapitate syndrome”. Treatment recommendations for capitate fractures have been established on very limited experience, as they are such a rare
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Pisiform Fractures of the pisiform tend to occur due to direct trauma to the hypothenar eminence. The Pisiform sits within the tendon of FCU and has multiple ligamentous attachments, hence an avulsion-type mechanism can also cause fracture. Fractures are difficult to recognize for many reasons; they can be associated with other upper extremity injuries, plain radiographs may not clearly depict the bone, or it is simply not considered and specifically looked for clinically or radiologically. Fifty percent of pisiform fractures are associated with other injuries such as distal radius, hamate, or triquetrum fractures and these must be sought out by careful examination of the
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and still attached by the strong radiolunate ligament, although this ligament can be compromised or in some cases completely ruptured. A so-called “lesser arc” injury is purely ligamentous, whereas a “greater arc” injury involves carpal or forearm bone fracture24 (Figures 5 and 6). This is usually either the radial styloid, scaphoid, capitate, triquetrum, or ulna styloid, or a combination of these bones. This classification is based on the PA view of the wrist, but Hertzberg25 also described a classification taking into account the lateral view and described the injury as volar or dorsal, based on whether the capitate was positioned dorsally or volarly to the lunate, irrelevant as to whether the lunate was still congruent with the lunate fossa or not. Urgent closed reduction of these injuries is mandatory to avoid compartment syndrome and median nerve compression by the extruded lunate and also to restore perfusion via the stretched and distorted vascular structures. Reduction is usually possible with adequate analgesia, and muscle relaxation. Care should be taken to apply prolonged gentle traction for 10 min with image intensifier screening throughout. Chinese finger traps can be used for this purpose (See Summary Box 3). Occasionally open reduction of the dislocated lunate may be needed via an extended carpal tunnel approach. Definitive treatment should be operative repair or stabilization of the affected ligaments and bones, as simple closed reduction and splinting has no place in the treatment perilunate injury. Scaphoid fractures should be fixed with a compression screw, and
X-rays and further imaging requested if suspicion arises. The pisiform may fracture transversely, longitudinally, or in a stellate fashion similar to other sesamoid bones. Fixation of pisiform fractures, even if very displaced, is not recommended and so treatment in a short arm cast for 4e6 weeks, or acute excision of fragments while preserving FCU are the treatments of choice. Secondary arthritis or non-unions can also be treated with careful excision. If an ulna nerve lesion presents along with a pisiform fracture, after reasonable dismissal of other contributing causes, it should be treated expectantly as most are neurapraxias and are more vulnerable to exploration than conservative treatment. Trapezoid The trapezoid is enclosed by the second metacarpal, trapezium, scaphoid, and capitate, and in this secure position it is the least commonly fractured carpal bone. Clearly it is important to look for other injuries as a fractured trapezoid indicates a high energy injury. The bone can be visualized quite well on standard PA, oblique and lateral X-rays. Close attention should be paid to the congruence of the surrounding joints to assess for subluxation or dislocation, particularly of the second CMC joint of the index finger, dislocation of the trapezoid can occur, usually in a dorsal direction.22 Minimally displaced fractures are treated with a short arm cast until pain subsides, whilst those which are displaced, have an intra-articular step, or subluxation of a joint should be reduced and stabilized with wires or screws. Chronic pain at the second CMC joint can be treated with fusion, with little detriment to hand motion or function.
Transverse and axial disruption of the carpus It is important to mention the various permutations of carpal dislocations, subluxations, and ligament injuries. Transverse injury e perilunate injury Perilunate injuries are the most common type of carpal dislocation and can be hugely disruptive injuries, resulting long term in secondary arthritic changes in the wrist. The injury classically occurs when the wrist is loaded through the thenar eminence, resulting in forced supination, dorsiflexion, and ulna deviation, although “reverse perilunar disruption” can occur when the force is applied through the hypothenar eminence resulting in injury propagating from the ulna side of the wrist first. Perilunate injuries are commonly missed in the emergency department, as the initial swelling can be relatively minor and padiographic difficult to interpret by the inexperienced eye. They can have devastating consequences if inadequately treated and even delayed repair has poorer outcomes, with instability, pain, avascular necrosis and secondary degenerative changes ensuing. Mayfield described four stages of perilunar disruption starting firstly with scapholunate injury, and then progressing circumferentially around the lunate, to next affect lunocapitate joint stability. Then the injury extends in an ulnar direction to affect the lunotriquetral articulation.23 A stage 4 injury represents complete dislocation of the lunate bone, usually hinged volarly
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Figure 5 A lesser arc injury involves purely soft tissue.
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Transverse injury e radiocarpal dislocation Radiocarpal dislocations are a rare occurrence and the most common direction is for the carpus to dislocate dorsal to the radius.26 It is likely that there will be an associated intercarpal ligamentous injury, or fracture of the radius due to ligament avulsion or impaction. Swift progression to closed reduction and decompression of swollen compartments should be undertaken in the emergency setting, and similarly closed treatment has no role in the definitive management of these patients. Anatomical reduction of joints and fractures, ligamentous repair, and temporary stabilization of joints with wires should be aggressively employed. If possible, transfixing the radiocarpal joint with wires should be avoided, but temporary bridging external fixation may be used. CMC joint disruptions have been covered in detail by Dean and Little in an earlier publication of Orthopaedics and Trauma.21 Axial carpal dislocations Axial carpal dislocations are very rare and result from very high energies and are therefore more commonly open than closed. They are more easily diagnosed in the emergency department due to the soft tissue discontinuity or dramatic swelling. The plain X-rays may reveal discontinuity in Gilula’s arcs and may give clues as to the path of forces across the wrist causing the injury, and hence indicate which structures have been damaged and are in need of repair. The carpal disruption may be radial or ulnar to the capitate, or both.27,28 These devastating injuries should be treated with particular attention to wound debridement, protection of neurovascular structures and the prevention of, or release of, established compartment syndrome. As with perilunate injuries fixation of scaphoid fractures, displaced carpal fractures, repair of important intercarpal ligaments and stabilization with wires should occur, but with these injuries the outcome is dependent primarily on the soft tissue defects. Complete extrusion of a carpal bone should be dealt with by repositioning and stabilizing it rather than discarding it.29
Figure 6 A greater arc injury passes through one or more bony structures.
at least the scapholunate ligament acutely repaired (bone anchors may be required) and the other affected interosseous discontinuities reduced and held with percutaneous wires. The wrist is splinted in a short arm plaster. Open reduction must be performed if anatomical reduction is not achieved by closed means. Wires will need to be retained for 8 weeks and hence must be buried to minimize risks of infection, and then later removed.
Conclusion
Reduction of dorsal perilunate dislocation C
Requirements: B Analgesia þ muscle relaxation B Prolonged traction for atraumatic relocation B Image intensifier screening
C
Reduction manoeuvre: B Longitudinal traction with elbow bent for 10 min B Extension of wrist 30e45 degrees B Clinicians thumb supports lunate on volar side of wrist B Gentle wrist flexion until capitate relocates over lunate B X-rays to assess reduction B Splint in short arm cast with wrist in neutral B Neurovascular observations B Definitive treatment planning e need anatomical reduction
Fractures and dislocations of the carpal bones can cause significant impairment and limitation of function. They are a varied group of injuries ranging from those with much understated signs and radiographs, to those with blatant and alarming deformity and overlying soft tissue damage. X-rays have to be scrutinized carefully to identify the more subtle injuries in order that expedient treatment can occur, and so that long-term complications can be avoided in this generally young and active population of patients. Treatment can be simplified into those injuries which require expectant care with splintage and those intra-articular fractures, displaced fractures, or dislocations which require early reduction and stabilization in order to avoid problems with stiffness, instability, secondary arthritis, and avascular necrosis in a complex and sensitive area of the body. All patients should receive immediate reduction of dislocations along with decompression of the carpal tunnel and 10 myofascial compartments of the hand if there is any suspicion of impending or established compartment syndrome.
Summary Box 3
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14 Clay NR, Dias JJ, Costigan PS, Gregg PJ, Barton NJ. Need the thumb be immobilised in scaphoid fractures? A randomised prospective trial. J Bone Joint Surg Br 1991 Sep; 73: 828e32. 15 Dias JJ. Definition of union after acute fracture and surgery for fracture nonunion of the scaphoid. J Hand Surg Br 2001 Aug; 26: 321e5. 16 Dias JJ, Wildin CJ, Bhowal B, Thompson JR. Should acute scaphoid fractures be fixed? A randomized controlled trial. J Bone Joint Surg Am 2005 Oct; 87: 2160e8. 17 Dias JJ, Dhukaram V, Abhinav A, Bhowal B, Wildin CJ. Clinical and radiological outcome of cast immobilisation versus surgical treatment of acute scaphoid fractures at a mean follow-up of 93 months. J Bone Joint Surg Br 2008 Jul; 90: 899e905. 18 Yin ZG, Zhang JB, Kan SL, Wang P. Treatment of acute scaphoid fractures: systematic review and meta-analysis. Clin Orthop Relat Res 2007 Jul; 460: 142e51. 19 Modi CS, Nancoo T, Powers D, Ho K, Boer R, Turner SM. Operative versus nonoperative treatment of acute undisplaced and minimally displaced scaphoid waist fractures e a systematic review. Injury 2009 Mar; 40: 268e73. 20 Boulas HJ, Milek MA. Hook of the hamate fractures. Diagnosis, treatment, and complications. Orthop Rev 1990 Jun; 19: 518e29. 21 Dean BJF, Little CL. Fractures of the metacarpals and phalanges. Orthopaedics and Trauma 2010; 21: 43e56. 22 Yasuwaki Y, Nagata Y, Yamamoto T, Nakano A, Kikuchi H, Tanaka S. Fracture of the trapezoid bone: a case report. J Hand Surg Am 1994 May; 19: 457e9. 23 Mayfield JK, Johnson RP, Kilcoyne RK. Carpal dislocations: pathomechanics and progressive perilunar instability. J Hand Surg Am 1980 May; 5: 226e41. 24 Johnson RP. The acutely injured wrist and its residuals. Clin Orthop Relat Res 1980 Jun; 149: 33e44. 25 Herzberg G, Comtet JJ, Linscheid RL, Amadio PC, Cooney WP, Stalder J. Perilunate dislocations and fracture-dislocations: a multicenter study. J Hand Surg Am 1993 Sep; 18: 768e79. 26 Dunn AW. Fractures and dislocations of the carpus. Surg Clin North Am 1972 Dec; 52: 1513e38. 27 Garcia-Elias M, Dobyns JH, Cooney 3rd WP, Linscheid RL. Traumatic axial dislocations of the carpus. J Hand Surg Am 1989 May; 14: 446e57. 28 Grabow RJ, Catalano 3rd L. Carpal dislocations. Hand Clin 2006 Nov; 22: 485e500. abstract vievii. 29 Papadonikolakis A, Mavrodontidis AN, Zalavras C, Hantes M, Soucacos PN. Transscaphoid volar lunate dislocation. A case report. J Bone Joint Surg Am 2003 Sep; 85-A: 1805e8.
Patients should be counselled early on in their management about the likely protracted course of recovery and rehabilitation so that their expectations echo our own knowledge of these challenging injuries. A
REFERENCES 1 Cohen MS. Fractures of the carpal bones. Hand Clin 1997 Nov; 13: 587e99. 2 Wolfe SW, ed. Green’s operative hand surgery. 6th edn. Philadelphia: Churchill Livingstone, 2011. 3 Brondum V, Larsen CF, Skov O. Fracture of the carpal scaphoid: frequency and distribution in a well-defined population. Eur J Radiol 1992 Sep; 15: 118e22. 4 Parvizi J, Wayman J, Kelly P, Moran CG. Combining the clinical signs improves diagnosis of scaphoid fractures. A prospective study with follow-up. J Hand Surg Br 1998 Jun; 23: 324e7. 5 Gilula LA. Carpal injuries: analytic approach and case exercises. AJR Am J Roentgenol 1979 Sep; 133: 503e17. 6 Jedlinski A, Kauer JM, Jonsson K. X-ray evaluation of the true neutral position of the wrist: the groove for extensor carpi ulnaris as a landmark. J Hand Surg Am 1995 May; 20: 511e2. 7 Yang Z, Mann FA, Gilula LA, Haerr C, Larsen CF. Scaphopisocapitate alignment: criterion to establish a neutral lateral view of the wrist. Radiology 1997 Dec; 205: 865e9. 8 Stewart NR, Gilula LA. CT of the wrist: a tailored approach. Radiology 1992 Apr; 183: 13e20. 9 Breitenseher MJ, Metz VM, Gilula LA, et al. Radiographically occult scaphoid fractures: value of MR imaging in detection. Radiology 1997 Apr; 203: 245e50. 10 Yin Y, Wilson AJ, Gilula LA. Three-compartment wrist arthrography: direct comparison of digital subtraction with nonsubtraction images. Radiology 1995 Oct; 197: 287e90. 11 Failla JM, Amadio PC. Recognition and treatment of uncommon carpal fractures. Hand Clin 1988 Aug; 4: 469e76. 12 Kukla C, Gaebler C, Breitenseher MJ, Trattnig S, Vecsei V. Occult fractures of the scaphoid. The diagnostic usefulness and indirect economic repercussions of radiography versus magnetic resonance scanning. J Hand Surg Br 1997 Dec; 22: 810e3. 13 Farnell RD, Dickson DR. The assessment and management of acute scaphoid fractures and non-union. Orthopaedics and Trauma 2010; 24: 381e93.
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(iv) Wrist arthroscopy
joint release (arthrolysis), synovectomy, ganglia resection, midcarpal fusion ("four-corner fusion"), and many more.
Javier Ferreira Villanova
Basic setup
Juan Gonzalez Del Pino
In general, a 2.4 or 2.7 mm 30 angled, short-barrel (50 to 60 mm) scope with a camera is used. There exist a wide variety of traction techniques and an extensive supply of traction devices that may be used to provide joint distraction. In most cases 10 lbs of traction is necessary for an adequate intra-articular visualization. Traction towers provide not only distraction but also the ability to place the wrist in various degrees of flexion, extension and radial and ulnar deviation. The majority of surgeons perform wrist arthroscopy with the patient in a supine position on the operating table, with the upper extremity secured to the arm table (Figure 1). Adequate fluid distension is provided by a continuous inflowoutflow system but one of the main complications is fluid extravasation and the risk of compartment syndrome, if it is to be used for a substantial amount of time. Some surgeons recommend a dry technique without the need of fluid irrigation5 and by combining sequential washout and aspiration this risk is reduced. The most commonly used technique is a gravitypowered irrigation system in which the height of the bags of fluid correlates with intra-articular pressure and the degree of joint distension.5 Useful arthroscopic equipment includes a joint probe, grasping forceps, basket forceps and power equipment (burrs and shavers). Small arthroscopic knives are helpful for TFCC resection and release of joint adhesions.
Abstract Wrist arthroscopy is nowadays a commonly used procedure employed in the diagnosis and treatment of traumatic pathologies, such as triangular fibrocartilage injuries, distal radius fractures, malunions and scaphoid fractures, as well as degenerative conditions such as scapholunate €ck’s disease and dorsal wrist ganglia advanced collapse, wrist, Kienbo cysts. Several procedures have recently been undertaken arthroscopically, such as radial styloidectomy, distal ulnar excision (“wafer procedure”), and proximal row carpectomy. Wrist arthroscopy has become the “gold standard” for the diagnosis of certain wrist injuries such as scapholunate instability. Compared to open techniques, arthroscopic procedures improve the postoperative management in terms of pain and early movement thus allowing an earlier return to work and resumption of daily living activities.
Keywords arthroscopy; ligaments; triangular fibrocartilage; wrist
Introduction
Anatomy & portals
Arthroscopy of the wrist has undergone many modifications and improvements since it was first described by Cheng in 1979.1 It has evolved from being a diagnostic modality to become a valuable and effective therapeutic tool. Arthroscopy has revolutionized the diagnosis and treatment of some articular injuries such as scapholunate (SLIL), lunotriquetral (LTIL) interosseous ligament injuries and triangular fibrocartilage (TFCC) tears.2,3 Arthroscopy provides the capability of examining directly all the intra-articular structures involved. Furthermore, wrist arthroscopy is a useful adjunctive tool in the reduction of intraarticular distal radius fractures and the assessment of concomitant ligament lesions. The advent of new portals e both dorsal and volar e is allowing the surgeon to approach the wrist from, virtually, any perspective, giving rise to the “box concept”.4 The staging of degenerative conditions has been facilitated through the use of the arthroscope, leading to new classifications and therapeutic approaches. Innovative surgeons have continued developing techniques such as proximal row carpectomy (PRC),
The site of wrist arthroscopy portals is critical for an adequate arthroscopic view. The approach should be done through a careful skin incision, followed by controlled penetration of to the capsule with a blunt trochar or a haemostat. In order to achieve a full wrist examination, it is quite important to follow a systematic procedure. It is mandatory to palpate all the articulations and joints to rule out either cartilage or ligament injuries (Figure 3). Radiocarpal dorsal portals The standard portals for wrist arthroscopy are mostly dorsal. Those dorsal portals that allow access to the radiocarpal joint
Javier Ferreira Villanova MD Consultant Orthopaedic Surgeon, Upper Extremity Surgery Unit, Orthpaedic Surgery Department, Guadalajara University Hospital. Guadalajara. Spain and Hand Institute, Rosario Hospital, Madrid, Spain. lez Del Pino MD PHD Consultant Orthopaedic Surgeon, Unit of Juan Gonza Hand and Wrist Surgery, Department of Orthopaedic Surgery, Santa Cristina University Hospital Madrid, Spain and Hand Institute, Rosario Hospital, Madrid, Spain.
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Figure 1 Basic operation room set up for a wrist arthroscopy.
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Midcarpal portals Four portals have been shown to be useful for a full view of the midcarpal space.6 The most common portal used for midcarpal arthroscopy is the radial midcarpal (MCR). This portal is located 1 cm distal to the 3-4 radiocarpal portal and in line with the radial margin of the third metacarpal. Through this portal the joint between the capitate and the concave surface of the scaphoid and the scapholunate, lunatotriquetral and capitohamate joints can be seen. The second most useful portal is the ulnar midcarpal portal (MCU), which is located on the midaxial line of the fourth metacarpal and enters the joint at the four-corner intersection between the lunate, triquetrum, hamate, and capitate. There are also two accessory portals. One of them is placed on the radial side of the midcarpal space, entering the scaphotrapeziotrapezoid (STT) joint. This portal is located just to the ulnar side of the EPL tendon at the level of the articular surface of the distal scaphoid. We must take care to avoid injury to the small branches of the radial nerve while placing this portal. The other accessory portal is at the ulnar aspect of the wrist and enters the triquetrohamate (TH) joint, and it is located just ulnar to the extensor carpi ulnaris (ECU) tendon. This is an excellent portal for an inflow or outflow cannula, and can also be used as a portal for a probe or another instrument to access the TH joint.
Figure 2 Dorsal extensor compartments of the wrist. Dorsal portals are located and named according to them.
are named in relation to their position with the dorsal extensor compartments (Figure 2). There are five main dorsal portals: 12, 3-4, 4-5, 6R and 6U. Normally wrist arthroscopy begins at the 3-4 portal, as it gives an excellent view of the volar aspect of the whole wrist. The portal is placed in the “soft spot” located just distal to the Lister’s tubercle, between the extensor pollicis longus (EPL) and the extensor digitorum communis (EDC) tendons. The rest of the radiocarpal portals are developed under direct vision using a 22-gauge needle to first establish a correct placement.
Figure 3 1) Scope inside the 3-4 portal. We can see the volar aspect of the radiocarpal joint, starting with the extrinsic volar ligaments, the radioscaphocapitate and the long radiolunate ligaments. 2) From the 3-4 portal the ulnar structures such as the TFCC (Triangular Fibrocartilage Complex) an be examined. 3) Midcarpal view from the midcarpal radial portal. A Type 2 lunate can be appreciated. 4) Radiocarpal vision from the 6R portal. The dorsal capsule as well as the dorsal aspect of the radius and carpus can be addressed through that portal; RSC: Radioscaphocapitate ligament. LRL: Long radiolunate ligament. TFC: Triangular fibrocartilage.
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Atzei’s TFCC complex peripheral tears classification. This new classification takes into consideration the instability of the DRUJ as well as the involvement of the proximal or foveal attachment of the triangular fibrocartilage, with therapeutic indications Class
DRUJ instability
Affected TFCC part
TFCC healing
DRUJ cartilage
Treatment
1 2 3 4 5
None/slight Mild/severe Mild/severe Severe Mild/severe
Distal Distal þ proximal Proximal Proximal e
Good Good Good Poor e
Good Good Good Good Poor
Suture Foveal reattachment Foveal reattachment Reconstruction Salvage
Atzei A, Rizzo A, Luchetti R, Fairplay T. Arthroscopic foveal repair of triangular fibrocartilage complex peripheral lesion with distal radioulnar joint instability. Tech Hand Upper Extrem Surg 2008; 12: 226e35.
Table 1
Radiocarpal volar portals The reason for approaches to the wrist from the dorsal aspect arose from the relative lack of neurovascular structures, as well as the familiarity of most surgeons with dorsal approaches to the radiocarpal joint. However, there are still some risks, especially during the learning curve.7 Volar portals have been recently
Midcarpal arthroscopy allows the visualization and palpation of the midcarpal structures. The STT joint is a common location for development of chondral lesions and or degenerative osteoarthritis. The proximal pole of the hamate is another common location for similar lesions. All those lesions can be addressed and treated arthroscopically.
Figure 4 TFCC (Triangular Fibrocartilage Complex) suture. Top left: Suture retriever (Micro SutureLassoTM Arthrex Inc. Naples. FL). Top right: The second end is retrieved through the same portal. Bottom left: Suture knotting. Bottom right: TFCC tension can be tested through the 6R portal.
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studied and popularized by Slutsky.8 There are five main/ principal volar portals: volar radial (VR), volar ulnar (VU), volar radial midcarpal (VRM), volar ulnar midcarpal (VUM) and the volar distal radioulnar joint (DRUJ).9
Indications Post-traumatic lesions of the wrist, such as TFCC tears, interosseous ligament lesions and fractures of the distal radius or the carpus still remain the main indications for a diagnostic or therapeutic arthroscopy. Ulnocarpal disorders Triangular fibrocartilage complex: one of the most common indications for wrist arthroscopy is the diagnosis and treatment of TFCC derangements when non-operative treatment has been unsuccessful. The treatment of choice is either a debridement or a repair, Studies concerning TFCC vascularity, have shown that both the central and radial aspects of the TFCC are largely avascular. We know that DRUJ instability is the most functionally disabling condition that can result from injury to the TFCC. The prime stabilizers of the DRUJ are the dorsal and palmar radioulnar ligaments and the triangular fibrocartilage. The fovea of the ulna is the functional and anatomic origin of the radioulnar ligaments. The term “meniscus homologue” has been used to denote the ulnar sling or leash of tissue that sweeps distally from the surface of the fibrocartilage disk to attach at the articular margin of either the triquetrum or the LTIL. The ECU sub-sheath and the volar ulnocarpal ligaments do not appear to contribute significantly to the DRUJ stability. Wrist arthroscopy has become the gold standard for the diagnosis and staging of TFCC lesions, since triple-injection arthrography and magnetic resonance imaging (MRI) are not entirely satisfactory. According to Palmer’s classification,10 there are four types of acute TFCC lesions. This classification system remains useful, but it does not clarify the most critical issue: the presence or absence of DRUJ instability. In particular, the term “class 1B injury” is now being used to describe two distinct entities: a lesion that is fully stable at the DRUJ (i.e., central fibrocartilage disc separation from the dorsal wrist capsule) and a lesion that produces DRUJ instability (i.e., radioulnar ligament avulsion from the ulnar fovea). A great confusion has been generated in both the evaluation and management of class 1B injuries. The critical distinction is in differentiating injuries that produce instability of the distal radioulnar joint from those that do not. Atzei and coworkers had developed a new classification attending to this important issue (Table 1). Based on the arthroscopic findings, five classes of TFCC peripheral tears are recognized, and guidelines for specific treatment can be considered.11 Palmer class 1A lesions in patients with neutral or negative variance are routinely debrided, since they yield excellent to good results, with no requirement for further surgery. The class 1A lesion is best approached from the dorsal 3-4 portal. Debridement of the disk is performed via the 6R portal. Resection is continued until a stable and smooth residual rim remains. Up to 80% of the substance can be resected without creating a secondary instability. The Palmer class 1B lesion involves injury to the ulnar attachment of the TFCC, either by ligament avulsion from the fovea or due to a fracture through the base of the ulnar styloid. Both subtypes result in DRUJ instability. Just because the damage
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Figure 5 Arthroscopic “wafer” resection. Top: TFCC Type 2C tear. Middle: Tear debridement using a basket forceps. Bottom: Final result after 3mmresection of the ulna head.
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is located in a well vascularized portion of the TFCC, and therefore the healing process can be promoted by suturing these lesions, arthroscopic repair is recommended. The main purpose of such techniques is to suture the torn TFCC to the dorsal ulnocarpal joint capsule and the ECU tendon sub-sheath. Inside-out, outside-in or all-inside techniques have been described as useful to restore TFCC tautness (Figure 4). However these techniques do not address DRUJ instability, and therefore they cannot be a treatment choice in the case of true 1B lesions. When a class 1B is suspected, we must assess the TFCC tension by the “trampoline test” and the hook test. The last one seems to be the best way to check the foveal attachment of the TFCC. Therefore, a DRUJ arthroscopy is needed when a hook test is positive. Well-preserved articular cartilage is mandatory for ligament repair or reconstruction of the DRUJ. Lately, some authors have recommended foveal reattachment of this type of lesions by means of transosseous implants. Promising results have been reported.11,12 There is still controversy regarding the management of class 1D lesions, which can be treated either by debridement or repair. We suggest that those tears that involve the dorsal radioulnar ligament, the volar radioulnar ligament or both, compromising DRUJ stability, should be repaired.
pronation and supination is essential during the entire procedure (Figure 5). An LTIL instability or ulnocarpal ligament rupture or laxity in the presence of an ulna abutment syndrome will not respond to an arthroscopic ulnar shortening (wafer procedure). This is due to the fact that arthroscopic ulna shortening does not address the LTIL or ulnocarpal instability. In order to minimize intra-articular scar formation, the arthroscopic wafer procedure requires an early postoperative mobilization e active and passive range of motion exercises. At about 4 months patients are expected to be pain-free. Ligament injuries Scapholunate ligament injuries: scapholunate interosseous ligament injuries are one of the most common causes of mechanical wrist pain. Despite the increase in knowledge about carpal injuries and improvements in radiological evaluation, the diagnosis of a SLIL tear may be difficult or missed. Arthroscopy has become the gold standard for diagnosis of SLIL injuries, allowing direct vision of both intrinsic and extrinsic ligaments. The articular cartilage state can be checked under static condition as well as during the dynamic mode. We believe that all suspected injuries of the SLIL should undergo arthroscopy. Scapholunate instability without radiocarpal arthritis has been classified into pre-dynamic, dynamic, and static.15 Nowadays there is a wide variety of arthroscopic classifications of this instability. Geissler and co-workers have proposed one which is the most widely used arthroscopic classification.16 Depending on the findings at the radiocarpal and midcarpal arthroscopy, it provides four degrees of injury (Table 2). Many of the SLIL injuries can be managed arthroscopically. Partial SLIL tears of the membranous portion of the ligament, without evidence of instability e pre-dynamic stage e can be addressed by means of debridement of the damaged tissue using a basket forceps or a radiofrequency probe. It seems that instability is not increased by the debridement unless the dorsal and anterior portions of the ligament complex are removed. In those cases where we notice a dynamic dorsal radiocarpal impingement, a dorsal rim milling of the distal radius using a 2.9 burr is recommended (Figure 6). Although the natural history of these lesions is not well known, a dorsal radiocarpal impingement
Ulnocarpal abutment: the ulnocarpal abutment syndrome refers to a painful overload of the ulnocarpal joint. Based on its patho-anatomy, this condition has been classified by Palmer et al. as a class 2 injury.10 Patients presenting with a symptomatic TFCC tear in combination with an ulnar zero or ulnar plus variance are unlikely to respond to a simple debridement of the TFCC.13 Because of the efficacy of the open wafer distal ulna resection as a treatment for ulnar impaction syndrome, several authors have communicated good results with an arthroscopic wafer procedure for ulnocarpal abutment.14 Wafer resection is performed through the 3-4 and 6R portals. The central disc is excised using a basket forceps or a radiofrequency probe, it being mandatory that the dorsal and volar radioulnar ligaments are preserved. Once the ulnar head is visualized, a shaver is used to remove the remaining cartilage from the ulnar head. Afterwards a 2.9 mm burr is advanced through the 6R portal and a 3 mm bony resection is effected. Care must be taken not to affect the sigmoid notch. In order to ensure a complete resection, full
Geissler’s interosseous ligament injury classification Grade
Radiocarpal view
Midcarpal view
Carpal bones gap
I
Attenuation/haemorrhage of the interosseous ligament Attenuation/haemorrhage of the interosseous ligament Incongruence/step off of carpal alignment Incongruence/step off of carpal alignment
No incongruence/step off
None
Incongruence/step off of carpal alignment
Less than the width of the probe
Incongruence/step off of carpal alignment Incongruence/step off of carpal alignment
Probe passes between the carpal bones 2.7 mm arthroscope passes between the carpal bones
II III IV
Geissler WB, Freeland AE, Savoie FH, et al. Carpal Instability Associated with Intra-articular Distal Radius Fractures. Proceedings, American Academy Orthopedic Surgeons Annual Meeting, San Francisco, 1993.
Table 2
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Figure 6 Dorsal radiocarpal impingement. 1) From the 6R portal a ganglion on the dorsal aspect of the scapholunate interval is seen. Fraying of the central portion of the scapholunate ligament is also noticed. 2) Resection of the dorsal ganglion. 3) Debridement of the dorsal lip of the radius. 4) Final appearance.
could worsen the SLIL injury, causing a complete tear, and may contribute to a chronic scapholunate instability condition. In cases where instability is seen (dynamic stage), debridement alone is not sufficient. There is a current controversy regarding the best treatment for these injuries. Some studies are reporting good results with arthroscopic debridement and thermal shrinkage.17,18 Although heat can shrink some tissues, postoperative protection is required during the first few months to maintain the tension while the tissue heals and regains normal function. The critical safe temperature range for achieving thermal shrinkage of tissue without permanent, irreparable damage is believed to be 65e75 C. When faced with a reducible static scapholunate instability, we recommend an arthroscopic reduction of the scaphoid-lunate (ARASL) articulation, that has been described by Hausman et al.19 A compression headless cannulated screw (HCS e Headless Cannulated Screw e Synthes GmbHÒ, Oberdorf) will provide a safe and solid construct, allowing permanent reduction of the scapholunate gap (Figure 7). A more rapid and aggressive postoperative rehabilitation programme is advocated. Wrist fractures Persistent displacement of the articular surface after an intraarticular fracture of the distal radius may predispose to the development of early post-traumatic osteoarthritis. Achieving no more than 1 mm of articular step-off has been recommended as
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Figure 7 Midcarpal view of a 3.0mm headless cannulated screw (HCS -Headless Cannulated Screw-. Synthes GmbHÒ, Oberdorf) across the scapholunate interval during an ARASL (Arthroscopic Reduction Association Scaphoid Lunate) procedure.
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Figure 8 Left: X-Ray AP view of an apparently 2-fragment distal radius fracture. Right: When the fracture is scoped, a 4-fragment fracture is clearly seen. Fracture lines are located at the scaphoid fossa, lunate fossa and dorsal radius; SF: Scaphoid fossa fragment. LF: Lunate fossa fragment. DR: Dorsoradial fragment.
Other indications
the treatment goal. On the other hand, no single technique of intra-operative radiographic imaging has been shown to allow for a reliable measurement of the anatomic fracture reduction (Figure 8). An arthroscopic approach to these problems can be used to cleanse the joint of blood and debris, and to identify for repair the associated ligamentous injuries. Concomitant carpal lesions are reported with an incidence of 25e75% of distal radial fractures, and should be included in the treatment algorithm, especially in young patients. Arthroscopy can also assess minimal articular step-off or gapping after the reduction and stabilization of the fracture. A few studies have suggested that arthroscopic monitoring of the articular alignment has been found superior to an image intensifier view alone.20 Arthroscopic reduction is less invasive than open reduction in managing articular displaced fragments of the articular surface of the distal radius. Open visualization of the articular congruity is advisable only through a dorsal exposure. Complications of wrist fractures such as joint capsule contracture and secondary wrist stiffness can be successfully managed by arthroscopic release. The procedure includes excision of scar tissue on the dorsal and volar aspect of the radiocarpal joint, reducing articular steps and TFCC debridement.21
Ganglion excision: it is well known that dorsal wrist ganglia, the most common tumour-like condition about the wrist, can be treated successfully by arthroscopy, with acceptable recurrence rates (0e20%). Good aesthetic and functional outcomes are advantages of the arthroscopy approach compared to the complications sometimes encountered with open surgery. We use the technique popularized by Osterman and Raphael.22 Because the ganglion is normally located on the radial side of the wrist, the arthroscopic excision is performed under dorsal vision, with a conventional 2.4 mm arthroscope in the 6R portal. The stalk of the ganglion is visualized better from the ulnar side. We use a 2.5 mm shaver introduced inside the ganglion across the 3-4 or the MCR portal. It is also important to perform a dorsal synovectomy, as well as a dorsal capsulotomy to prevent recurrences. Postoperative care includes early active wrist motion, avoiding strenuous work and weight-lifting. Other disorders: as occurs in other joints, impingement of articular surfaces can lead to degenerative changes of these articulations. Some of them have already been explained (i.e., ulnocarpal abutment and dorsal radiocarpal impingement). One
Figure 9 Hamatolunate impingement. Left: Proximal pole chondromalacia. Right: Proximal pole resection.
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such subset of patients includes those with arthritic changes of the proximal pole of the hamate. Viegas et al. found a statistically higher incidence of cartilage erosion with exposed subchondral bone on the proximal hamate in those wrists with a hamateelunate articulation than in those without this anatomical pattern.23 In full ulnar deviation of the wrist, the hamate and lunate impinge at this level. An increased prevalence of tears of the LTIL in patients with proximal hamate osteoarthritis has been noticed. Harley et al. proposed the acronym HALT (hamate arthrosis lunotriquetral ligament tear) wrist to describe this clinical condition.24 A 2.4 mm resection of the proximal pole of the hamate is performed to fully unload the hamateelunate articulation while leaving the loads across the triquetralehamate unchanged (Figure 9). Ulnar styloid impaction syndrome, first described by Topper, is a common cause of ulnar-sided wrist pain, due to the contact between a long ulnar styloid and the triquetrum.25 Initially it was managed with an open excision of the distal ulnar styloid, but arthroscopic procedures have been developed.26 Arthroscopy gives the chance to explore the rest of the wrist, especially the lunotriquetral joint and the ULL and UTL, as well as to perform styloidectomy under direct vision, without harming neighbouring structures (Figure 10).
Finally, many other procedures have been advocated and reported about the benefits of arthroscopy, such as: arthroscopic partial wrist fusion (STT fusion, four-corner fusion) and proximal row carpectomy. These procedures are successfully addressed in expert hands, but still are yet to become safe and reproducible procedures.
Complications Complications related to arthroscopy are similar to those at other joints. They are uncommon, with authors reporting rates of approximately 2%, and are clearly related to the surgeon’s experience and the procedure performed.29 Most complications can be managed by non-operative treatment. Care must be taken with creation of portal sites because of possible injury with the extensor tendons, radial artery, and branches of the radial and ulna nerves. The extensor pollicis longus is the tendon most at risk during wrist arthroscopy. A good wrist anatomy knowledge and meticulous portal dissection significantly reduce the number of postoperative complications. Thermal ablation can produce serious complications such as tendon ruptures and full thickness burns.30 Burns can also occur in the volar side of the forearm due
€ck’s disease: wrist arthroscopy has become a valuable Kienbo €ck’s disease. assessment and a primary treatment tool for Kienbo It allows identification of the nonfunctional joints and tailoring of the surgical reconstructions depending on the anatomic findings. Bain et al. developed an arthroscopic classification system to €ck’s disease.27 This new classification pays attenassess Kienbo tion to the articular damage at the radiocarpal and midcarpal joints, establishing the treatment according to the number and location of the affected joints. Menth-Chiari et al. have reported good results with the use of arthroscopic debridement, especially in terms of pain relief and range of motion.28
Figure 10 Arthroscopic stiloidectomy: Debridement of the ulnar styloid through the 6R portal; S: Ulnar styloid. ECU: Extensor carpi ulnaris.
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Figure 11 Skin burn of the forearm due to heat transmission across the traction device.
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11 Atzei A, Rizzo A, Luchetti R, Fairplay T. arthroscopic foveal repair of triangular fibrocartilage complex peripheral lesion with distal radioulnar joint instability. Tech Hand Upper Extrem Surg 2008; 12: 226e35. 12 Iwasaki N, Minami A. Arthroscopically assisted reattachment of avulsed triangular fibrocartilage complex to the fovea of the ulnar head. J Hand Surg [Am] 2009; 34: 1323e6. 13 Ishikawa J, Suenaga N, Kasashima T. Clinical results of treatment of triangular fibrocartilage complex tears by arthroscopic debridement. J Hand Surg [Am] 1996; 21: 406e11. 14 Tomaino MM, Weiser RW. Combined arthroscopic TFCC debridement and wafer resection of the distal ulna in wrists with triangular fibrocartilage complex tears and positive ulnar variance. J Hand Surg [Am] 2001; 26: 1047e452. 15 Watson H, Ottoni L, Pitts EC, Handal AG. Rotary subluxation of the scaphoid: A spectrum of instability. J Hand Surg [Br] 1993; 18: 62e4. 16 Geissler WB, Freeland AE, Savoie FH, et al. Carpal instability associated with intra-articular distal radius fractures. San Francisco: Proc AAOS, 1993. 17 Darlis NA, Weiser RW, Sotereanos DG. Partial scapholunate ligament injuries treated with arthroscopic debridement and thermal shrinkage. J Hand Surg [Am] 2005; 30: 908e14. 18 Hirsh L, Sodha S, Bozentka D, et al. Arthroscopic electrothermal collagen shrinkage for symptomatic laxity of the scapholunate interosseous ligament. J Hand Surg [Br] 2005; 30: 643e7. 19 Hausman MR. Arthroscopic RASL. In: Slutsky D, Nagle D, eds. Techniques in wrist and hand arthroscopy. Philadelphia: Churchill Livingstone, 2007; 79e85. 20 Edwards II CC, Haraszti CJ, McGillivary GR, et al. Intra-articular distal radius fractures: arthroscopic assessment of radiographically assisted reduction. J Hand Surg [Am] 2001; 26: 1036e41. 21 Luchetti R, Atzei A, Fairplay T. Arthroscopic wrist arthrolysis after wrist fracture. Arthroscopy 2007; 23: 255e60. 22 Osterman AL, Raphael J. Arthroscopic resection of dorsal ganglion of the wrist. Hand Clin 1995; 11: 7e12. 23 Viegas SF, Wagner K, Patterson R, Peterson P. Medial (hamate) facet of the lunate. J Hand Surg [Am] 1990; 15: 564e71. 24 Harley BJ, Werner FW, Boles D, et al. Arthroscopic resection of arthrosis of the proximal hamate: a clinical and biomechanical study. J Hand Surg [Am] 2004; 29: 661e7. 25 Topper SM, Wood MB, Ruby LK. Ulnar styloid impaction syndrome. J Hand Surg [Am] 1997; 22: 669e704. 26 Bain GI, Bidwell TA. Arthroscopic excision of ulnar styloid in stylocarpal impaction. Arthroscopy 2006; 22: 677.e1e3. 27 Bain GI, Begg M. Arthroscopic assessment and classification of Kienbock’s disease. Tech Hand Upper Extrem Surg 2006; 10: 8e13. 28 Menth-Chiari WA, Poehling GG, Wiesler ER, et al. Arthroscopic debridement for the treatment of Kienbock’s disease. Arthroscopy 1999; 15: 12e9. 29 Culp RW. Complications of wrist arthroscopy. Hand Clin 1999; 15: 529e35. 30 Pell RF, Uhl RL. Complication of thermal ablation in wrist arthroscopy. Arthroscopy 2004; 6: 84e6.
to the heat of the traction tower after sterilization (Figure 11). It is therefore mandatory to check the temperature of the tower before starting the procedure.
Summary As we come to understand wrist arthroscopy patho-anatomy better, and given the huge advances in technical devices, we are now able to perform new diagnostic and therapeutic procedures. The variety of treatments using wrist arthroscopy is expanding and brings new challenges, and also controversies. Wrist arthroscopy is the gold standard in the diagnosis and treatment of TFCC injuries. Excellent outcomes have been obtained with debridement in partial SLIL and LTIL ligament tears. However, in complete tears with static instability pattern, debridement should be augmented by pinning or by means of a headless compression screw (ARASL procedure). The use of the newer electro-thermal devices is promising; however, further investigation is needed to better define their efficacy and safety. The role of arthroscopy in the treatment of distal radius fractures should be individualized according to the patient and the surgeon, but according to published studies, can be of great help in verifying the existence of associated injuries and the correct articular reduction. Outcomes of dorsal ganglia arthroscopic resection show excellent results. Further studies are required to evaluate the role of arthroscopy in the management of volar ganglia. The clinical applications of wrist arthroscopy continue to expand, with more complex reparative, reconstructive, and salvage procedures. Future developments are likely to occur by adapting open reconstructive procedures into arthroscopic procedures. A
REFERENCES 1 Cheng YCh. Arthroscopy of the wrist and finger joints. Orthop Clin North Am 1979; 10: 723e33. 2 Weiss AP, Akelman E, Lambiase R. Comparison of the findings of triple-injection cinearthrography of the wrist with those of arthroscopy. J Bone Joint Surg [Am] 1996; 78: 348e56. 3 Cooney WP. Evaluation of chronic wrist pain by arthrography, arthroscopy, and arthrotomy. J Hand Surg [Am] 1993; 18: 815e22. 4 Bain G, Munt J, Turner PC. New advances in wrist arthroscopy. Arthroscopy 2008; 24: 355e67. ~al F, Garcia-Bernal FJ, Pisani D, et al. Dry arthroscopy of the 5 del Pin wrist: surgical technique. J Hand Surg [Am] 2007; 32: 119e23. 6 Viegas SF. Midcarpal arthroscopy: anatomy and technique. Arthroscopy 1992; 8: 385e90. 7 Puhaindran ME, Yam AK, Chin AY, Lluch A, Garcı´a-Elı´as M. Wrist arthroscopy: beware the novice. J Hand Surg [Eur] 2009; 34: 540e2. 8 Slutsky DJ. Volar portals in wrist arthroscopy. J Am Soc Surg Hand 2002; 2: 225e32. 9 Slutsky DJ. Clinical applications of volar portals in wrist arthroscopy. Tech Hand Upper Extrem Surg 2004; 8: 229e38. 10 Palmer AK. Triangular fibrocartilage disorders: injury patterns and treatment. Arthroscopy 1990; 6: 125e32.
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FURTHER READING ~al F, Mathoulin C, Luchetti R, eds. Arthroscopic management of Del Pin distal radius fractures. Heidelberg: Springer, 2010.
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Radiographic assessment of primary hip arthroplasty
Introduction: the need for radiographic review Radiographic assessment of total hip arthroplasty (THA) is required to establish the technical success of the procedure, monitor progress, identify patients in need of revision surgery or specialist referral and potentially to predict outcome. Investigations such as computed tomography (CT), magnetic resonance imaging (MRI) and radio-isotope scanning (RIS) are increasingly undertaken but radiographic assessment remains the mainstay of arthroplasty review.1 THA failure occurs in a bimodal pattern; soon after surgery due to faulty components or technical failure and much later on, when the construct is “wearing out”.2 Clinical failure usually lags behind radiographic failure,3 so early intervention is desirable. Routine radiographs may detect asymptomatic signs,4,5 and those associated with premature or imminent failure should prompt action or referral. Failing constructs, whether symptomatic or not, are at risk of periprosthetic fracture,6 which is difficult to treat and has substantial morbidity and mortality.7 Revision of a failing implant is best performed sooner rather than later, when bone stock is still available for reconstruction.5,8
Ruy E da Assunc‚~ao Benjamin J R F Bolland Stuart Edwards Leonard J King Douglas G Dunlop
Abstract Assessment of total hip arthroplasty with plain radiography remains the first choice of investigation for postoperative review and investigation of any subsequent symptoms or problems. A working knowledge of the radiographic appearance of hip arthroplasty and how this appearance changes with time is important to identify potential or evolving problems. Most of our knowledge of these radiographic features comes from observations made from arthroplasty outcome studies rather than directed research and as such, is not readily available as a single resource. This article summarizes the features seen after primary total hip arthroplasty and how they may evolve, with a brief review of the underlying biological and biomechanical principles. The technical assessment of the postoperative radiograph is considered, together with important landmarks and subsequent long-term changes. We emphasize the importance of appreciating features that identify patients at risk for revision surgery and reinforce the concept that changes may vary depending on the type of implant used. With basic principles of radiology, biology and biomechanics, orthopaedic surgeons and radiologists can accurately assess the majority of radiographs taken after total hip arthroplasty.
Standards and timing of radiographs Radiographs are taken immediately postoperatively and thereafter at the discretion of the unit, depending on resources for follow-up or research requirements. The absence of any radiographic changes at 1 year is a good prognostic indicator9 and many units discharge their patients at this stage (or sooner). However, changes may appear after this time and follow-up radiographs are indicated in younger patients. Radiographs are typically an anteroposterior (AP) of the pelvis, centred on the pubis (or lower to include the entire prosthesis) with the patient supine and a “shootthrough” lateral (Lowenstein or Johnson) view of the implanted hip. Additional views may be required, depending on the extent of the reconstruction or pathological changes. In particular, pelvic osteolysis should be assessed with three views (AP, 45 iliac oblique and 60 obturator oblique) if CT is not available.10 Radiographs need to be identical in orientation and if possible, magnification. It should be noted that any measurements based on plain radiographs are only accurate to approximately 2e3 mm.11 Scaling, measurement and analysis have been greatly facilitated by the advent of electronic patient archiving and communication systems (PACS). There is no difference in accuracy between manual measurements made on digitized images and plain radiographs,12 but specialized software may assess component position and detect component migration with greater accuracy.13e15
Keywords bone remodelling; osteolysis; radiography; total hip replacement
~o Ruy E da Assunc‚a Centre, Oxford, UK.
FRCS (Tr&Orth)
Clinical Fellow, Nuffield Orthopaedic
Benjamin J R F Bolland MD FRCS (Tr&Orth) Hip Fellow, Princess Elizabeth Orthopaedic Centre, Royal Devon and Exeter NHS Foundation Trust, Exeter, UK.
Principles of osteolysis Stuart Edwards FRCS (Tr&Orth) Consultant Orthopaedic and Trauma Surgeon, Aut Even Hospital, County Kilkenny, Ireland.
The principles of implant biomechanics and subsequent construct behaviour are well covered in basic texts and recent reviews16,17 but a brief discussion of the relevant bone biology is warranted. Periprosthetic radiographic osteopaenia (reduced radiodensity than otherwise similar radiographs of the same patient) may only become apparent when 30e70% of bone mass is lost, hence quantitative assessment with plain radiographs is unreliable.18e20 Osteopaenia may be assessed quantitatively with CT21 or dual energy X-ray absorptiometry (DEXA).19,22 This process of
Leonard J King FRCP FRCR Consultant Radiologist, Southampton University Hospitals NHS Trust, Southampton, UK. Douglas G Dunlop FRCS FRCSEd(Tr & Orth) MD Consultant Orthopaedic and Trauma Surgeon, Honorary Senior Clinical Lecturer, Southampton University Hospitals NHS Trust, Southampton, UK.
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resorption in low stress areas leading to osteopaenia is termed stress shielding and is a radiographic feature of both cemented and uncemented implants. Osteolytic lesions (as opposed to preexistent bone cysts) usually communicate with the joint space but this may only be apparent with CT.23 An osteolytic lesion may be defined radiographically as a demarcated, non-linear lytic lesion measuring >3 mm in diameter,24 although definitions may vary. Polyethylene or other wear particles from bearing surfaces gain ingress to boneeimplant or cementebone interfaces via joint fluid which penetrates these interfaces25,26 and osteolysis may therefore appear at any point around the implant. Polished cemented stems demonstrate less fluid movement at both interfaces (boneecement, stemecement) than matt cemented stems, which have a higher incidence of osteolysis.27 Initiation of osteolysis may be avoided if access to the cement/bone interface is prevented by sound fixation, either with cement or osseointegration.28 This is important because osteolytic loosening is self-perpetuating due to the loose components allowing further ingress of particles.25 Metal debris from metal-on-metal bearings may induce a lymphocytic response29 through a delayed hypersensitivity pathway30 with similar outcomes. This process, termed aseptic lymphocytic vasculitis associated lesion (ALVAL)31,32 is not well understood.33 Metallosis may lead to significant soft tissue destruction and the formation of cystic or solid “pseudotumours” which may not be visible on plain radiographs. Ultrasound or MRI examination may aid diagnosis.34 CT studies show that plain radiographs underestimate the extent of osteolysis by at least 20%35 and CT is increasingly used to investigate pelvic osteolysis with greater accuracy.1,23 Osteolysis is more prevalent in the presence of a polyethylene bearing but stress shielding doesn’t appear to be affected by bearing materials.36
Figure 1 Bilateral total hip replacements, cemented polished taper stem and cemented cup on the right, uncemented stem and cup on the left. a: Vertical axis migration, b: interteardrop line, c: horizontal axis migration, d: alternative vertical axis migration, e: obturator line, f: alternative horizontal axis migration, g: Kohler’s line, h: stem subsidence, j: alternative stem subsidence, k: “white-out” of acetabular cement, m: “cementoma” medial to medial acetabular wall, n: acetabular screw, p: inclusion radiolucencies in cement mantle, q: centralizer, r: cement plug, s: spotwelds, t: pedestal.
Postoperative assessment Cemented acetabular components On the pelvic AP view, the acetabulum is divided radially from the centre of rotation to the periphery of the cup into three zones39 (Figure 2). Note that Figure 2 shows an uncemented cup for demonstration purposes. These zones are used to localize any radiographic findings such as radiolucency in bone or cement. In the immediate postoperative radiograph, the cement mantle around the cup should be of even thickness (2e5 mm) in the three zones. “Pooling” of cement at the inferomedial cup/bone interface (zone 3) is a common error due to insufficient medialization of the cup and is often associated with deficient cement in zone 1. Radiolucency or absence of cement in zone 1 may predict early failure.39,40 Bottoming out between the cup and the medial
Pelvic landmarks The pelvic landmarks with minimal variance in relation to the acetabular component are illustrated in Figure 1 and are used as reference points for measurement of acetabular position or migration.37 Although described for uncemented cups, the technique can be used for cemented cups. Migration on a vertical axis is best measured between the centre of the cup and perpendicular (Figure 1a) to the “inter-teardrop” line (Figure 1b), which touches the most inferior point of both the acetabular teardrops (cotyloid fossae). Migration on a horizontal axis is best measured between the centre of the cup and perpendicular to a vertical line through the centre of the teardrop (Figure 1c). If the teardrops are not visible, vertical migration is measured between the bottom of the cup (Figure 1d) and the obturator line (Figure 1e), which touches the superior cortical margin of both ischial bones (the inferior edge of the obturator foramen itself) and horizontal migration is measured between the centre of the cup and perpendicular (Figure 1f) to Kohler’s line (Figure 1g), which touches the medial edge of the ilium and the medial cortical edge of the ischium (the lateral edge of the obturator foramen itself). The most consistent landmarks for measuring and assessing stem subsidence are a consistent chosen point on the lateral shoulder of the stem and the tip of the greater trochanter38(Figure 1h) although some authors recommend the most medial point of the lesser trochanter12 (Figure 1j). Consistency of measurement and identically oriented radiographs are the key to accuracy, although detailed measurements are seldom required to make a clinical decision.
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Figure 2 Acetabular and femoral zones. Arrow: lucency after insertion of shell.
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acetabular wall is undesirable, as are radiolucencies at any interface or in the cement mantle.3,40 Well-compressed cement interdigitates with trabecular bone, creating a “white-out” between the cement and the bone (Figure 1k). The quality of the cement mantle around the cup can be graded according to Ranawat.3 The cup is divided into zones as previously mentioned and a score assigned to each zone based on the postoperative radiograph. A lower grade of cement mantle is associated with a higher risk of loosening. In addition, the presence of acetabular protrusio or a preoperative diagnosis of inflammatory arthritis or hip dysplasia may be associated with higher failure rates.3 The presence of a “cementoma” (Figure 1m) is seldom of clinical significance, although the exothermic curing reaction of boneecement may burn soft tissues at the time of surgery.41 Cement extruded medially through the acetabular floor into the pelvis may predict difficulty at revision due to vascular proximity or adhesion, but is more commonly seen inferior and medial to the acetabulum. The position of the acetabular component is critical to the clinical outcome and may affect wear rates, dislocation, impingement and range of motion.15,42e44 However, postoperative radiographic assessment is complex.15 The simplest method (in addition to assessing position as described above in “Pelvic landmarks”) is to measure the angle (q angle)45 between a tangential line drawn across the open face of the cup and the interteardrop line44 on the AP (Figure 3q). This represents acetabular abduction or inclination. Optimal inclination is thought to be 45 , within a range of approximately 30 e55 .15 On the lateral view, the angle between the tangential across the open face of the cup and a line perpendicular to the horizontal plane (Figure 3a) represents acetabular version.42 Whether the cup is anteverted, neutral or retroverted relative to the perpendicular should be specified. The optimal position is thought to be 15 e20 of anteversion.15 If pelvic position is inconsistent or in doubt, anteversion may be measured relative to a line drawn between the anterior superior iliac spine and the pubis (Figure 3b). Definitions of acetabular orientation may vary from study to study and it is important to appreciate their differences and specify which definition (and thus measurement result) has been used. These definitions are operative, radiological and anatomical, measuring version around a transverse, oblique and longitudinal axis respectively. In general, the operative definition of acetabular inclination and version, as described above, should be used to describe THA. Nomograms can be used to convert one measurement to another, allowing studies to be compared.45 Using mathematical and trigonometric techniques, anteversion may be measured from the AP but all radiographic assessment of version remains inaccurate.46 CT, image intensification or specialized software may all improve accuracy.15,45
Figure 3 Acetabular inclination and version. q: inclination angle, a: anteversion angle, b: alternative plane of reference. Figure reproduced with permission of Elsevier from Review of Orthopaedics, Ed. Miller, 3rd edn, 2004.
between the cup and the acetabular floor in the immediate postoperative period (Figure 2, arrow). This is usually of little consequence if <1 mm, and “fills in” with time.48,49 The presence of this line varies from implant to implant; a hemispherical cup should be fully impacted (and the line therefore represents incomplete impaction) whereas a non-hemispherical cup (a socalled rim-fit or expanded cup) will frequently have a line despite being fully impacted. A simple rule of thumb is to reassess any minor radiolucent lines at 12e24 months to ensure that they have filled in and in more severe cases, confirm that the shell has not migrated (“spun out”) in the short term. Overenthusiastic impaction of an uncemented cup may result in fracture of the acetabulum in 0.4% of cases50 which may lead to early loss of position. In cases without displacement it may be possible to treat the patient expectantly, albeit with more frequent radiographic review to confirm union and cup fixation.
Uncemented acetabular components Uncemented cups should be implanted in the same position described above. Screws, when present, are commonly directed superiorly into the ilium (Figure 1n) but may be directed into the ischium or pubis in complex cases. Clearly, screws penetrating the pelvis via the medial acetabular wall or elsewhere are highly undesirable due to the intra-operative risk of visceral or vascular injury. Screws are not always required and are variably present on the radiograph.47 Commonly, a radiolucent line is present
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Cemented femoral components Like the acetabulum, the bone (and cement, if present) around the femoral stem can be divided into zones, seven on the AP view and
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seven on the lateral view51 to localize abnormalities in bone or cement (Figures 2 and 4). The stem should be central in the femoral canal on the AP and lateral views, with a uniform cement mantle. Minimal amounts of varus or valgus are probably of little importance but significant malposition, particularly varus may result in early failure.51,52 There are no absolute values to quantify the extent of malposition in the coronal or sagittal planes. Limb length can be assessed by comparing the distance between a horizontal line passing through the most medial aspect of the lesser trochanter and the obturator line. It should be borne in mind that lengths may be affected by discrepancies elsewhere in the lower limb and conclusions cannot be drawn from the AP pelvis alone, unless the patient is weight-bearing without correction. Comparison with preoperative films is crucial. The cement mantle should be uniform and not contain defects. Isolated radiolucencies adjacent to the stem or bone usually represent air or blood trapped during the insertion or polymerization process (Figure 1p), which may act as stress risers for fatigue fracture.53 Uniform lucency surrounding the tip of a polished taper stem usually represents a centralizer containing a void into which the stem can subside (Figure 1q). Below this, a cement plug is seen as a uniform radiolucency with or without a metallic marker bead (Figure 1r).The presence of extruded cement around the femur suggests cement escape through a pre-existent defect in the femur, a nutrient artery foramen or an iatrogenic fracture. Good penetration of cement into bone will result in a “white-out” with blurring of the interface between bone and cement, particularly further down the stem. The quality of the postoperative cement mantle on the pelvic AP view has been graded by Barrack54 as follows: grade A e complete filling of the medullary canal with cement (“whiteout”), grade B e partial radiolucency at the cement/bone interface, grade C e radiolucency of 50e99% of the cement/bone interface, grade D e radiolucency of 100% in any view at the cement/bone interface or incomplete filling such that the stem tip is uncovered. A poor quality cement mantle may be more prone to early failure, particularly with deficiency in zone 5 and 6.40,55 In summary, the quality of the cement mantle is critical to the successful outcome in cemented THA.3,16
future subsidence, the stem should be in apposition with the inner cortex, although the extent of this varies with the design of the stem. Proximally coated (ie proximally fixed) stems should ideally fill at least 90% of the proximal femur56 and a good press-fit is associated with future osseointegration.56 The femur should be scrutinized for evidence of defects on the inner cortex created by intra-operative broaching, which may act as stress risers for periprosthetic fracture. Likewise, excessive impaction may cause intra-operative periprosthetic fracture57,58 and this should be sought, particularly around the medial calcar and lesser trochanter. The level of neck resection for an uncemented stem may affect the leg length and excessive resection (resection below the midpoint of the neck) may reduce torsional stability, particularly in proximally-loading stems (wedge shaped stems without a diaphyseal fill).59 Hip resurfacing components The acetabular component should be positioned as mentioned previously, erring towards a lower inclination angle (40 ) to minimize excessive wear, metal ion release and metallosis.60e62 The femoral component stem should be positioned centrally in the femoral neck on AP and lateral views and angulated parallel within the cortices of the femoral neck. If not parallel, it is preferable to have a slightly valgus rather than varus orientation on the AP.63e65 This more closely replicates the normal lines of force on the inferior femoral neck and medial calcar.66 The femoral component can be considered valgus if the postoperative stemshaft angle (SSA) is 5 or more greater than the preoperative shaft-neck angle (SNA) and varus if the SSA is >5 less than the preoperative SNA.66,67 Figure 5 demonstrates a varus femoral component. Since the cement remains within the femoral component, a cement mantle is not visible through the metal of the component, although cement penetration may be occasionally visible around the stem. The femoral neck should be scrutinized for intra-operative notching of the superior femoral neck cortex, which may act as a stress riser for femoral neck fracture65,66(Figure 6a). Reamed cancellous bone left uncovered by an incompletely impacted femoral component may also predispose to fracture.64 Both components can be divided into zones66 to localize any changes with time (Figure 7).
Uncemented femoral components The position of an uncemented stem is ideally as described above, central in the femoral canal in the AP and lateral views. To avoid
Radiographic changes with time Abnormalities immediately apparent on routine postoperative radiographs are usually a result of technical error or difficulties during surgery.3,40 However, as the boneeimplant construct ages, changes may develop, irrespective of surgical technique or initial appearance, and it is difficult to predict when a construct will fail based on a single image, even in the presence of profound abnormalities. Therefore, progression of these features is the key to identifying potential problems. The decision to intervene surgically is based on clinical symptoms and patient characteristics as well as the radiographic appearance. Detailed formats exist for the documentation of radiographic changes but these are usually utilized for research purposes rather than routine review.68 Fracture of the femoral component itself is well described in cemented and uncemented stems69e72 and are easily identified. This represents failure of the construct but is increasingly rare with current generations of implant.
Figure 4 Femoral zones (lateral).
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Figure 7 Hip resurfacing, femoral and acetabular zones.
their differing biomechanical modes, composite beam and taper slip stems cannot have the same radiographic criteria for failure.73 In principle, composite beam stems should not migrate perceptibly at all but polished taper stems can be expected to subside marginally within the cement mantle. Modes of stem failure have been described by Gruen51 as follows: pistoning (stem in cement or cement in bone), medial midstem pivot, calcar pivot or bending cantilever. These modes of failure apply to cemented composite beam stems but may be relevant to polished taper stems. It may be simpler to think of stem failure as occurring in only two ways: failure of the cement mantle (ie failure at the stemecement interface or pistoning) or failure at the boneecement interface (all other modes of failure).4 Migration of a composite beam stem >2.6 mm at 2 years has only a 5% chance of long-term success.38 Similarly, migration of 2 mm or more at 2 years combined with a radiolucent line (RLL) of 2 mm width or more predicts the need for revision in 50% of stems within 10 years (“rule of twos”). The presence of only one sign (migration or RLL) reduces the risk to 25% revision at 10 years.74 As defined by Harris,75 a composite beam stem is possibly loose if an RLL is present around 50e99% of the stem on any view, probably loose if there is an RLL around the entire stem on any view and definitely loose if there is any migration (stem/cement or cement/bone), stem fracture or cement fracture. Taper slip designs migrate perceptibly to the naked eye, although this can only be approximately measured on plain radiographs (see “Standards and timing of radiographs”). As a polished taper stem subsides within the cement mantle, a stemecement lucency usually appears at the shoulder of the stem, reflecting the distance the stem has subsided. This should slow to a rate not visible to the naked eye at 1 year.76,77 This can be summarized as
Figure 5 Hip resurfacing, component in varus. SSA: stem/shaft angle. SNA: shaft/neck angle. a: Femoral neck narrowing.
Features of cemented components Migration and failure: there is no consensus as to the radiographic definition of failure but certain consistent features have been identified that predict the need for revision surgery. Due to
Figure 6 Hip resurfacing with femoral neck fracture. a: Superior cortical notch.
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the “rule of ones”: normal subsidence is approximately 1 mm in the first year and 1 mm over the next 10 years. Generally, they subside less than 2 mm although this may be higher on occasion. A cemented polyethylene socket with a metal backing may occasionally be seen. These are associated with a high failure rate and are no longer in widespread use.78 Migration of the acetabular component of 3 mm or more (including rotation) is considered failure.3,9
osteolysis (Figure 8e) are prone to fracture and this should be sought.52 Radiolucencies around cups tend to be linear but may become expansile, so-called “balloon osteolysis”83,84(Figure 8c). Plain radiography remains the most common form of initial pelvic assessment and is a useful screening tool for both cemented and uncemented cups.1,85 Stress shielding: proximal osteopaenia due to stress shielding is a feature of a well-fixed stable composite beam stem86 and probably does not affect clinical outcome.87 Loss of radiodensity is most apparent around the medial calcar and is associated with “rounding off” of the sharp osteotomized edge of the calcar.4 This change is not clinically important.4,52 Proximal stress shielding (typically osteopaenia in zones 1, 7, 8 and 14 of, Figure 8f) associated with cortical hypertrophy at the tip of the stem may be a feature of a well-fixed composite beam stem that is loading the femur distally, rather than coming loose. However, hypertrophy at the distal stem is evidence of proximal loosening if associated with radiolucency around the stem80(Figure 8g). Stress shielding around the cemented acetabular component occurs medially to the cup and is often transient, with bone mineral density (BMD) returning to normal at 2 years.88
Radiolucencies: the appearance of previously undocumented radiolucencies in the femoral construct is the hallmark of loosening, particularly if these are progressive at the cement/bone interface.52 An exception is the appearance of the lucency at the shoulder of a taper slip stem described previously. Early appearance of radiolucencies (within a year or immediately postoperatively) is associated with a higher risk of failure.79 Debonding at the cementebone interface (Figure 8a), particularly at the lateral margin of the stem (zone 1 and 2) is associated with failure,9 as is cement fracture at any point, particularly at the tip of the stem.4,9,80 Cemented titanium stems are associated with more radiolucencies than cobalt chrome or stainless steel.81 Appearance of lucencies at the cement bone interface in zone 2 and 3 of the socket is associated with failure,9 but the extent of radiolucency around the cup is probably more relevant than the width or location of the lucency82 (Figure 8b). Hodgkinson82 classified demarcation at the cement/bone interface and suggested that loosening is more likely as the radiolucency extends around the cup.
Features of uncemented components Osseointegration and loosening: osseointegration occurs in up to 95% of stable stems,89 the remainder going on to stable fibrous fixation, when signs of osseointegration are not seen but there is no evidence of loosening.89e91 Major signs of osseointegration include: the absence of RLL’s, the presence of stress shielding and new trabeculation between the stem and endosteal bone (termed “spotwelding”)22,92 (Figure 1s). Spotwelds often form at surface or design junctions on the stem, for example the junction between porous, coated or untreated surfaces in proximally coated implants.90,92 Pedestal formation (a bar of endosteal bone extending to or under the tip of the stem) may commonly occur58 (Figure 1t) and may prevent subsidence of a loose stem. A pedestal is only indicative of loosening if the stem is surrounded by radiolucency18 and is a normal finding in stable stems (Figure 1t). Signs of instability or loosening include: migration of >2 mm over a year, RLL’s around the porous or coated part of the stem, a pedestal with RLL’s around the stem, medial calcar hypertrophy or increase in calcar radiodensity (indicating subsidence) or debonding of the porous or coated surface, seen as metallic fragmentation.92 Note that a proximally coated implant may be stable despite an RLL around the uncoated distal part of the stem as long as the coated section is osseointegrated.92 Signs of osseointegration of an uncemented acetabulum include: the absence of radiolucent lines, the presence of a superolateral buttress, medial stress shielding (osteopaenia), radial trabecula and an inferomedial buttress.93 Radiolucent lines are considered significant if they are greater than 1 mm in their widest diameter and involve more than one zone. A buttress is a column of dense bone extending superiorly from the superolateral aspect of the cup or medially from the inferomedial aspect. These buttresses are analogous to femoral spotwelds. Medial stress shielding is evident as reduced density medial to the cup. Radial trabeculation is evident as fine trabeculae extending perpendicularly from the cup in zones 1 or 2. These
Osteolysis: osteolysis is characterized by well defined areas of bony lucency that may become confluent as the process progresses (Figure 8c). Progress is variable but may be rapid and catastrophic. Osteolysis is frequently associated with excessive wear of the polyethylene cup as indicated by asymmetry of the head within the cup (Figure 8d). Thin cortices associated with
Figure 8 Bilateral cemented composite beam total hip replacements. a: Cement/bone lucency, b: acetabular lucency (osteolytic), c: acetabular (balloon) osteolysis, d: eccentric polyethylene wear, e: thin cortical wall, f: proximal stress shielding, g: cortical hypertrophy and radiolucencies, h: ectopic ossification.
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cortical density superior to the cup.21,101 As for the femur, existent anatomy and preoperative BMD probably affect the extent of the phenomenon.100
signs may become apparent from 2 to 3 years after surgery and 97% of cups with 3e5 signs are ingrown.93 83% of cups with only one or no signs are loose. Signs associated with loosening of an uncemented acetabulum include: the occurrence of RLLs or progression of these lines more than 2 years postoperatively, or the presence of radiolucent lines in all three zones. New or progressive lines of any width are significant, as are radiolucent lines in any zone of 2 mm or wider. Any migration (3 mm or more) indicates loosening. Small residual immediate postoperative gaps (Figure 2, arrow) usually “fill in” and disappear by 2 years and don’t appear to be clinically significant.49
Hip resurfacing Hip resurfacing has been less well studied but may be associated with specific findings, chief of which is femoral neck fracture (Figure 6). This usually occurs as a spontaneous acute event (not necessarily traumatic) and is thought to result from postsurgical avascular necrosis (AVN) of the femoral head and/or neck. Other features suggesting a higher fracture risk have been discussed. The development of radiolucency around the stem has been suggested to be undesirable63 and may be associated with subsequent component migration.66,67 The presence of “reactive sclerosis” at the tip of the stem is of uncertain significance but may predate the appearance of radiolucency, particularly when associated with superolateral notching.67 Radiostereometric analysis studies have shown that successful constructs do not migrate, so any component movement should be noted.102 Fracture of the stem has been reported but is extremely rare.103 Finite element modelling suggests that stress shielding of the femoral head and neck should occur, although this is not confirmed clinically.104,105 Spontaneous narrowing of the femoral neck (>10% of femoral neck diameter) is a phenomenon of unknown origin that may be seen in 27.6% cases at 5 years106 (Figure 5a). Narrowing appears to be established by 3 years and thus far, is of uncertain clinical significance.
Osteolysis: osteolysis is present in 12% of stems at 5 years, especially in zones 1 and 7 and may be seen from 3 years. Significant osteolysis (>1.5 cm2) in zone 1 may lead to spontaneous fracture of the greater trochanter.89 As for cemented stems, aggressive osteolysis is associated with polyethylene wear and failure.56 As opposed to the balloon osteolysis seen in cemented cups, osteolysis in uncemented cups is localized and locally expansive, particularly in association with screw holes, which presumably allow ingress of polyethylene debris particles.69,94 Osteolysis may result in significant destruction of the acetabulum, leading to migration of the cup or periprosthetic fracture.1 Progressive osteolysis is associated with polyethylene wear and large lesions (>10 cm3 as measured by CT) tend to progress.69 A single AP radiograph may obscure osteolysis over 83% of the cup surface10 and therefore additional views or CT are required for accurate assessment1 (see “Standards and timing of radiographs”). These CT protocols may quantify the defects,35,69 but ultimately, the extent of bone loss is established at revision surgery. Classification systems exist to guide surgical treatment.95e97
Ectopic ossification Ectopic ossification in peri-articular soft tissue after THA is very common (Figure 8h), with incidence reports ranging from 5% to 90%. Clinically significant ossification is thought to occur in 3e7% cases. Incidence may be reduced with postoperative radiotherapy or non-steroidal anti-inflammatories, although the clinical benefits are questionable. Ossification activity is first detected at approximately 3 weeks postoperatively on RIS and becomes visible from 6 weeks onwards on the plain radiograph.107,108 Ectopic ossification is graded according to Brooker,108 based on the extent of bone bridging across the joint, as seen on the AP radiograph. Grade 1: islands of bone in the soft tissues around the hip; grade 2: bony spurs from the femur and/or pelvis with a gap of >1 cm between them; grade 3: gap between spurs of <1 cm; grade 4: apparent ankylosis across the joint.
Stress shielding: in general population studies of uncemented THA, stress shielding is seen in up to 25% of femurs at 2 years and 29% at 5 years. Increased stress shielding may be associated with older patients, higher weight, female gender and increasing stem diameter (and hence stiffness).19,89,98 Stress shielding is more prominent in patients with low initial BMD or atrophic cortices22 and is prominent in Gruen zones 1 and 7.21,83 BMD may be reduced by 5e48% (mean 23%) in stable uncemented stems.22 Radiographic assessment of this bone loss is difficult since inter-observer agreement only becomes acceptable once 70% of bone mass is lost.20 Despite this, it is possible to estimate the extent of femoral stress shielding.90,99 The periprosthetic femur is divided into 16 zones of interest (eight on the AP view, eight on the lateral view) and the presence of reduced cortical density or thinning (compared to the postoperative index film) is noted in each zone, regardless of extent. Mild stress shielding involves 1e4 sites, moderate 5e7 sites and severe 8 or more sites. Minor variations in density between radiographs can be accounted for by assessing the same landmarks on different radiographs.90 Proximal osteopaenia is frequently associated with cortical hypertrophy around the distal stem in a well-fixed implant.48,92 Although much has been written about the phenomenon, it appears that stress shielding is of little clinical significance.89,100 Stress shielding also occurs around the uncemented acetabular component, although this is difficult to appraise radiographically.22 CT studies show stress shielding of cancellous bone medial to the implant with subsequent increased
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Conclusion The behaviour and radiographic appearances of cemented and uncemented implants in vivo have been well-documented and these findings are consistent with biomechanical principles. It should be borne in mind that different designs (of which there are many) may manifest these signs to a variable extent and it is not always possible to extrapolate the behaviour of one implant to another. Nevertheless, radiographic assessment of THA is an important part of monitoring the status of the implanted construct and detecting potential clinical problems, allowing these to be dealt with quickly and appropriately. Although the exact radiographic criteria for success and failure vary from report to report, these features are consistent enough to allow the surgeon to estimate the status of the construct and thus direct clinical decisions. A 359
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21 Schmidt R, Muller L, Kress A, Hirschfelder H, Aplas A, Pitto RP. A computed tomography assessment of femoral and acetabular bone changes after total hip arthroplasty. Int Orthop 2002; 26: 299e302. 22 Sychterz CJ, Claus AM, Engh CA. What we have learned about longterm cementless fixation from autopsy retrievals. Clin Orthop Relat Res 2002; 405: 79e91. 23 Kitamura N, Naudie DD, Leung SB, Hopper Jr RH, Engh Sr CA. Diagnostic features of pelvic osteolysis on computed tomography: the importance of communication pathways. J Bone Joint Surg Am 2005; 87: 1542e50. 24 Maloney WJ, Galante JO, Anderson M, et al. Fixation, polyethylene wear, and pelvic osteolysis in primary total hip replacement. Clin Orthop Relat Res 1999; 369: 157e64. 25 Schmalzried TP, Jasty M, Harris WH. Periprosthetic bone loss in total hip arthroplasty. Polyethylene wear debris and the concept of the effective joint space. J Bone Joint Surg Am 1992; 74: 849e63. 26 Anthony PP, Gie GA, Howie CR, Ling RS. Localised endosteal bone lysis in relation to the femoral components of cemented total hip arthroplasties. J Bone Joint Surg Br 1990; 72: 971e9. 27 Crawford RW, Evans M, Ling RS, Murray DW. Fluid flow around model femoral components of differing surface finishes: in vitro investigations. Acta Orthop Scand 1999; 70: 589e95. 28 Manley MT, D’Antonio JA, Capello WN, Edidin AA. Osteolysis: a disease of access to fixation interfaces. Clin Orthop Relat Res 2002; 405: 129e37. 29 Davies AP, Willert HG, Campbell PA, Learmonth ID, Case CP. An unusual lymphocytic perivascular infiltration in tissues around contemporary metal-on-metal joint replacements. J Bone Joint Surg Am 2005; 87: 18e27. 30 Park YS, Moon YW, Lim SJ, Yang JM, Ahn G, Choi YL. Early osteolysis following second-generation metal-on-metal hip replacement. J Bone Joint Surg Am 2005; 87: 1515e21. 31 Willert HG, Buchhorn GH, Fayyazi A, et al. Metal-on-metal bearings and hypersensitivity in patients with artificial hip joints. A clinical and histomorphological study. J Bone Joint Surg Am 2005; 87: 28e36. 32 Shimmin A, Beaule PE, Campbell P. Metal-on-metal hip resurfacing arthroplasty. J Bone Joint Surg Am 2008; 90: 637e54. 33 Korovessis P, Petsinis G, Repanti M, Repantis T. Metallosis after contemporary metal-on-metal total hip arthroplasty. Five to nineyear follow-up. J Bone Joint Surg Am 2006; 88: 1183e91. 34 Glyn-Jones S, Pandit H, Kwon YM, Doll H, Gill HS, Murray DW. Risk factors for inflammatory pseudotumour formation following hip resurfacing. J Bone Joint Surg Br 2009; 91-B: 1566e74. 35 Robertson DD, Sutherland CJ, Lopes T, Yuan J. Preoperative description of severe acetabular defects caused by failed total hip replacement. J Comput Assist Tomogr 1998; 22: 444e9. 36 Kim YH, Yoon SH, Kim JS. Changes in the bone mineral density in the acetabulum and proximal femur after cementless total hip replacement: alumina-on-alumina versus alumina-on-polyethylene articulation. J Bone Joint Surg Br 2007; 89: 174e9. 37 Massin P, Schmidt L, Engh CA. Evaluation of cementless acetabular component migration. An experimental study. J Arthroplasty 1989; 4: 245e51. 38 Walker PS, Mai SF, Cobb AG, Bentley G, Hua J. Prediction of clinical outcome of THR from migration measurements on standard radiographs. A study of cemented Charnley and Stanmore femoral stems. J Bone Joint Surg Br 1995; 77: 705e14. 39 DeLee JG, Charnley J. Radiological demarcation of cemented sockets in total hip replacement. Clin Orthop Relat Res 1976; 121: 20e32.
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40 Ritter MA, Zhou H, Keating CM, et al. Radiological factors influencing femoral and acetabular failure in cemented Charnley total hip arthroplasties. J Bone Joint Surg Br 1999; 81: 982e6. 41 Birch R, Wilkinson MC, Vijayan KP, Gschmeissner S. Cement burn of the sciatic nerve. J Bone Joint Surg Br 1992; 74: 731e3. 42 Woo RY, Morrey BF. Dislocations after total hip arthroplasty. J Bone Joint Surg Am 1982; 64: 1295e306. 43 D’Lima DD, Urquhart AG, Buehler KO, Walker RH, Colwell Jr CW. The effect of the orientation of the acetabular and femoral components on the range of motion of the hip at different head-neck ratios. J Bone Joint Surg Am 2000; 82: 315e21. 44 Patil S, Bergula A, Chen PC, Colwell Jr CW, D’Lima DD. Polyethylene wear and acetabular component orientation. J Bone Joint Surg Am 2003; 85-A(suppl 4): 56e63. 45 Murray DW. The definition and measurement of acetabular orientation. J Bone Joint Surg Br 1993; 75: 228e32. 46 Tannast M, Langlotz U, Siebenrock KA, Wiese M, Bernsmann K, Langlotz F. Anatomic referencing of cup orientation in total hip arthroplasty. Clin Orthop Relat Res 2005; 436: 144e50. 47 Curtis MJ, Jinnah RH, Wilson VD, Hungerford DS. The initial stability of uncemented acetabular components. J Bone Joint Surg Br 1992; 74: 372e6. 48 Galante JO, Jacobs J. Clinical performances of ingrowth surfaces. Clin Orthop Relat Res 1992; 276: 41e9. 49 Udomkiat P, Wan Z, Dorr LD. Comparison of preoperative radiographs and intraoperative findings of fixation of hemispheric porous-coated sockets. J Bone Joint Surg Am 2001; 83-A: 1865e70. 50 Haidukewych GJ, Jacofsky DJ, Hanssen AD, Lewallen DG. Intraoperative fractures of the acetabulum during primary total hip arthroplasty. J Bone Joint Surg Am 2006; 88: 1952e6. 51 Gruen TA, McNeice GM, Amstutz HC. “Modes of failure” of cemented stem-type femoral components: a radiographic analysis of loosening. Clin Orthop Relat Res 1979; 141: 17e27. 52 Pacheco V, Shelley P, Wroblewski BM. Mechanical loosening of the stem in Charnley arthroplasties. Identification of the “at risk” factors. J Bone Joint Surg Br 1988; 70: 596e9. 53 Jafri AA, Green SM, Partington PF, McCaskie AW, Muller SD. Preheating of components in cemented total hip arthroplasty. J Bone Joint Surg Br 2004; 86: 1214e9. 54 Barrack RL, Mulroy Jr RD, Harris WH. Improved cementing techniques and femoral component loosening in young patients with hip arthroplasty. A 12-year radiographic review. J Bone Joint Surg Br 1992; 74: 385e9. 55 Star MJ, Colwell Jr CW, Kelman GJ, Ballock RT, Walker RH. Suboptimal (thin) distal cement mantle thickness as a contributory factor in total hip arthroplasty femoral component failure. A retrospective radiographic analysis favoring distal stem centralization. J Arthroplasty 1994; 9: 143e9. 56 Dorr LD, Lewonowski K, Lucero M, Harris M, Wan Z. Failure mechanisms of anatomic porous replacement I cementless total hip replacement. Clin Orthop Relat Res 1997; 334: 157e67. 57 Nourbash PS, Paprosky WG. Cementless femoral design concerns. Rationale for extensive porous coating. Clin Orthop Relat Res 1998; 355: 189e99. 58 Shetty AA, Slack R, Tindall A, James KD, Rand C. Results of a hydroxyapatite-coated (Furlong) total hip replacement: a 13- to 15-year follow-up. J Bone Joint Surg Br 2005; 87: 1050e4. 59 Whiteside LA, White SE, McCarthy DS. Effect of neck resection on torsional stability of cementless total hip replacement. Am J Orthop 1995; 24: 766e70.
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60 Campbell P, Beaule PE, Ebramzadeh E, et al. The John Charnley Award: a study of implant failure in metal-on-metal surface arthroplasties. Clin Orthop Relat Res 2006; 453: 35e46. 61 Langton DJ, Jameson SS, Joyce TJ, Webb J, Nargol AV. The effect of component size and orientation on the concentrations of metal ions after resurfacing arthroplasty of the hip. J Bone Joint Surg Br 2008; 90: 1143e51. 62 Williams S, Leslie I, Isaac G, Jin Z, Ingham E, Fisher J. Tribology and wear of metal-on-metal hip prostheses: influence of cup angle and head position. J Bone Joint Surg Am 2008; 90(suppl 3): 111e7. 63 Beaule PE, Lee JL, Le Duff MJ, Amstutz HC, Ebramzadeh E. Orientation of the femoral component in surface arthroplasty of the hip. A biomechanical and clinical analysis. J Bone Joint Surg Am 2004; 86-A: 2015e21. 64 Amstutz HC, Campbell PA, Le Duff MJ. Fracture of the neck of the femur after surface arthroplasty of the hip. J Bone Joint Surg Am 2004; 86-A: 1874e7. 65 Shimmin AJ, Back D. Femoral neck fractures following Birmingham hip resurfacing: a national review of 50 cases. J Bone Joint Surg Br 2005; 87-4: 463e4. 66 Amstutz HC, Beaule PE, Dorey FJ, Le Duff MJ, Campbell PA, Gruen TA. Metal-on-metal hybrid surface arthroplasty: two to six-year followup study. J Bone Joint Surg Am 2004; 86-A: 28e39. 67 Hing CB, Back DL, Bailey M, Young DA, Dalziel RE, Shimmin AJ. The results of primary Birmingham hip resurfacings at a mean of five years: an independent prospective review of the first 230 hips. J Bone Joint Surg Br 2007; 89-B: 1431e8. 68 Johnston RC, Fitzgerald Jr RH, Harris WH, Poss R, Muller ME, Sledge CB. Clinical and radiographic evaluation of total hip replacement. A standard system of terminology for reporting results. J Bone Joint Surg Am 1990; 72: 161e8. 69 Howie DW, Neale SD, Stamenkov R, McGee MA, Taylor DJ, Findlay DM. Progression of acetabular periprosthetic osteolytic lesions measured with computed tomography. J Bone Joint Surg Am 2007; 89: 1818e25. 70 Wroblewski BM. Fractured stem in total hip replacement. A clinical review of 120 cases. Acta Orthop Scand 1982; 53: 279e84. 71 Ling RSM. The history and development of the Exeter hip. 2nd edn. Switzerland: Stryker Europe, 2004. 72 Harvie P, Haroon M, Henderson N, El-Guindi M. Fracture of the hydroxyapatite-ceramic-coated JRI-Furlong femoral component: body mass index and implications for selection of the implant. J Bone Joint Surg Br 2007; 89: 742e5. 73 Shen G. Femoral stem fixation. J Bone Joint Surg Br 1998; 80-B: 754e6. 74 Kobayashi A, Donnelly WJ, Scott G, Freeman MA. Early radiological observations may predict the long-term survival of femoral hip prostheses. J Bone Joint Surg Br 1997; 79: 583e9. 75 Harris WH, McCarthy Jr JC, O’Neill DA. Loosening of the femoral component of total hip replacement after plugging the femoral canal. Hip; 1982; 228e38. 76 Alfaro-Adrian J, Gill HS, Murray DW. Should total hip arthroplasty femoral components be designed to subside? A radiostereometric analysis study of the Charnley Elite and Exeter stems. J Arthroplasty 2001; 16: 598e606. 77 Alfaro-Adrian J, Gill HS, Murray DW. Cement migration after THR. A comparison of Charnley elite and exeter femoral stems using RSA. J Bone Joint Surg Br 1999; 81: 130e4. 78 Ritter MA, Faris PM, Keating EM, Brugo G. Influential factors in cemented acetabular cup loosening. J Arthroplasty 1992; 7(suppl): 365e7.
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79 Tapadiya D, Walker RH, Schurman DJ. Prediction of outcome of total hip arthroplasty based on initial postoperative radiographic analysis. Matched, paired comparisons of failed versus successful femoral components. Clin Orthop Relat Res 1984; 186: 5e15. 80 Loudon JR, Older MW. Subsidence of the femoral component related to long-term outcome of hip replacement. J Bone Joint Surg Br 1989; 71: 624e8. 81 Ebramzadeh E, Normand PL, Sangiorgio SN, et al. Long-term radiographic changes in cemented total hip arthroplasty with six designs of femoral components. Biomaterials 2003; 24: 3351e63. 82 Hodgkinson JP, Shelley P, Wroblewski BM. The correlation between the roentgenographic appearance and operative findings at the boneecement junction of the socket in Charnley low friction arthroplasties. Clin Orthop Relat Res 1988; 228: 105e9. 83 Zicat B, Engh CA, Gokcen E. Patterns of osteolysis around total hip components inserted with and without cement. J Bone Joint Surg Am 1995; 77: 432e9. 84 Harris WH. Results of uncemented cups: a critical appraisal at 15 years. Clin Orthop Relat Res 2003; 417: 121e5. 85 Kitamura N, Pappedemos PC, Duffy 3rd PR, et al. The value of anteroposterior pelvic radiographs for evaluating pelvic osteolysis. Clin Orthop Relat Res 2006; 453: 239e45. 86 Jasty M, Maloney WJ, Bragdon CR, Haire T, Harris WH. Histomorphological studies of the long-term skeletal responses to well fixed cemented femoral components. J Bone Joint Surg Am 1990; 72: 1220e9. 87 Harris WH. Will stress shielding limit the longevity of cemented femoral components of total hip replacement? Clin Orthop Relat Res 1992; 274: 120e3. 88 Shetty NR, Hamer AJ, Kerry RM, Stockley I, Eastell R, Wilkinson JM. Bone remodelling around a cemented polyethylene cup. A longitudinal densitometry study. J Bone Joint Surg Br 2006; 88: 455e9. 89 McAuley JP, Culpepper WJ, Engh CA. Total hip arthroplasty. Concerns with extensively porous coated femoral components. Clin Orthop Relat Res 1998; 355: 182e8. 90 Engh CA, Bobyn JD, Glassman AH. Porous-coated hip replacement. The factors governing bone ingrowth, stress shielding, and clinical results. J Bone Joint Surg Br 1987; 69: 45e55. 91 Glassman AH, Engh CA. The removal of porous-coated femoral hip stems. Clin Orthop Relat Res 1992; 285: 164e80. 92 Engh CA, Massin P, Suthers KE. Roentgenographic assessment of the biologic fixation of porous-surfaced femoral components. Clin Orthop Relat Res 1990; 257: 107e28. 93 Moore MS, McAuley JP, Young AM, Engh Sr CA. Radiographic signs of osseointegration in porous-coated acetabular components. Clin Orthop Relat Res 2006; 444: 176e83.
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94 Soto MO, Rodriguez JA, Ranawat CS. Clinical and radiographic evaluation of the Harris-Galante cup: incidence of wear and osteolysis at 7 to 9 years follow-up. J Arthroplasty 2000; 15: 139e45. 95 Gustilo RB, Pasternak HS. Revision total hip arthroplasty with titanium ingrowth prosthesis and bone grafting for failed cemented femoral component loosening. Clin Orthop Relat Res 1988; 235: 111e9. 96 D’Antonio JA, Capello WN, Borden LS, et al. Classification and management of acetabular abnormalities in total hip arthroplasty. Clin Orthop Relat Res 1989; 243: 126e37. 97 Paprosky WG, Perona PG, Lawrence JM. Acetabular defect classification and surgical reconstruction in revision arthroplasty. A 6-year follow-up evaluation. J Arthroplasty 1994; 9: 33e44. 98 Huiskes R, Weinans H, van Rietbergen B. The relationship between stress shielding and bone resorption around total hip stems and the effects of flexible materials. Clin Orthop Relat Res 1992; 274: 124e34. 99 Engh CA, Bobyn JD. The influence of stem size and extent of porous coating on femoral bone resorption after primary cementless hip arthroplasty. Clin Orthop Relat Res 1988; 231: 7e28. 100 Dorr LD, Bechtol CO, Watkins RG, Wan Z. Radiographic anatomic structure of the arthritic acetabulum and its influence on total hip arthroplasty. J Arthroplasty 2000; 15: 890e900. 101 Mueller LA, Kress A, Nowak T, et al. Periacetabular bone changes after uncemented total hip arthroplasty evaluated by quantitative computed tomography. Acta Orthop 2006; 77: 380e5. 102 Itayem R, Arndt A, McMinn DJ, Daniel J, Lundberg A. A five-year radiostereometric follow-up of the Birmingham Hip Resurfacing arthroplasty. J Bone Joint Surg Br 2007; 89: 1140e3. 103 Bowman NK, Bucher TA, Bassily AA. Fracture of the stem of the femoral component after resurfacing arthroplasty of the hip. J Bone Joint Surg Br 2006; 88: 1652e3. 104 Ong KL, Kurtz SM, Manley MT, Rushton N, Mohammed NA, Field RE. Biomechanics of the Birmingham hip resurfacing arthroplasty. J Bone Joint Surg Br 2006; 88: 1110e5. 105 Cordingley R, Kohan L, Ben-Nissan B. What happens to femoral neck bone mineral density after hip resurfacing surgery? J Bone Joint Surg Br 2010; 92-B: 1648e53. 106 Hing CB, Young DA, Dalziel RE, Bailey M, Back DL, Shimmin AJ. Narrowing of the neck in resurfacing arthroplasty of the hip: a radiological study. J Bone Joint Surg Br 2007; 89: 1019e24. 107 Board TN, Karva A, Board RE, Gambhir AK, Porter ML. The prophylaxis and treatment of heterotopic ossification following lower limb arthroplasty. J Bone Joint Surg Br 2007; 89: 434e40. 108 Brooker AF, Bowerman JW, Robinson RA, Riley Jr LH. Ectopic ossification following total hip replacement. Incidence and a method of classification. J Bone Joint Surg Am 1973; 55: 1629e32.
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SHOULDER
Acute first-time shoulder dislocation
dislocation can be anterior, posterior, inferior or superior, with anterior dislocation being by far the most common, accounting for up to 98% of reported cases. The estimated incidence of first-time anterior shoulder dislocation is between 0.08 and 1.69 per 1000 people per year with a prevalence of approximately 2%.1,2 Anterior dislocation (Figures 1 and 2) of the shoulder usually occurs when the arm is externally rotated, abducted and extended and a force displaces the humeral head anteriorly with respect to the glenoid and inferiorly with respect to the coracoid process, resulting in a subcoracoid dislocation. Other types of anterior dislocation include subglenoid (the humeral head lodges anterior and inferior to the glenoid), subclavian (the humeral head is medial to the coracoid), infrathoracic and intraperitoneal e these subtypes are normally associated with severe trauma. Posterior dislocation occurs as a result of axial loading of the adducted, internally rotated arm or with violent muscle contraction, such as occurs during an epileptic seizure or electric shock when the strong internal rotator muscles of the arm (pectoralis major, subscapularis, teres major, latissumus dorsi) overcome the relatively weak external rotators (infraspinatus and teres minor). The subtypes of posterior dislocation include subacromial (the most common), subglenoid and subspinous (humeral head medial to the acromion process and beneath the scapular spine). Inferior dislocations are rare and result from hyperabduction when the neck of the humerus abuts against the acromion and levers the humeral head out of the glenoid inferiorly. The head becomes locked under the glenoid with the humeral shaft pointing overhead, an appearance known as luxatio erecta. Superior dislocations are associated with fractures of the scapula and severe trauma.
Adam Rumian Duncan Coffey Simon Fogerty Roger Hackney
Abstract The shoulder is the most frequently dislocated joint in the human body, anterior dislocation being the most common variant. For stability, the glenohumeral joint relies on both static and dynamic restraints and dislocation often results in damage to these restraints. For example, antero-inferior capsulolabral complex damage often occurs as a result of anterior dislocations (a ‘Bankart lesion’) and impaction of the dislocated humeral head against the rim of the antero-inferior glenoid can result in a postero-lateral humeral head defect (the ‘HilleSachs lesion’). Prompt reduction of the dislocation is necessary to relieve pain and reduce the risk of complications, and should be performed as soon as possible in the emergency department, or in the operating theatre in cases with an associated shoulder fracture. Subsequent treatment of the dislocation is aimed at restoring function of the shoulder and minimizing the risk of recurrent instability. Non-surgical treatment is the conventional method of management after a successful closed reduction and involves immobilization of the affected shoulder for between 3 and 6 weeks coupled with, or followed by, physiotherapy. Young age at the time of the first anterior dislocation is associated with a high rate of recurrence and there is growing evidence that primary arthroscopic stabilization significantly reduces the rate of recurrent instability. This article outlines the current management strategies for dealing with this acute traumatic injury.
Glenohumeral stability The glenohumeral joint is a highly mobile joint, but in order to achieve the range of movement, stability is compromised, making the joint vulnerable to dislocations. The stability of the joint relies on both static and dynamic restraints. The static restraints are provided by the osseous anatomy, cartilage,
Keywords Bankart lesion; dislocation; HilleSachs lesion; instability; stabilization
Introduction The shoulder is the most frequently dislocated joint in the human body, accounting for 45% of all dislocations. The direction of
Adam Rumian MD FRCS(Tr&Orth) Consultant Orthopaedic Surgeon, Lister Hospital, East and North Herts NHS Trust, Stevenage, Hertfordshire, UK. Conflicts of interests: none. Duncan Coffey Medical Student, Leeds Medical School, Worsley Building, University of Leeds, Leeds, UK. Conflicts of interests: none. Simon Fogerty MBChB MRCS (Eng.) SpR in Orthopaedics, Leeds General Infirmary, Great George Street, Leeds, West Yorkshire, UK. Conflicts of interests: none. Roger Hackney FFSEM Dip Sports Med Chapel Allerton Hospital, Chapeltown Road, Leeds, UK. Conflicts of interests: none.
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Figure 1 Radiograph showing and anterior dislocation of the glenohumeral joint.
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first time in the presence of no, or minimal, trauma. Atraumatic dislocations can either be involuntary, when the patient experiences the dislocation unintentionally, or voluntary, when the patient has intentionally caused the shoulder to dislocate. Involuntary atraumatic dislocations are usually associated with hyperlaxity or some other deficiency of the static or dynamic restraints, for example in collagen disorders, congenital malformations or disturbances of neuromuscular control. Voluntary atraumatic dislocations are caused by a muscle patterning imbalance and may be associated with emotional instability, psychiatric disturbances and secondary gain issues.
Associated lesions Traumatic dislocation of the shoulder often results in damage to the structural integrity of the joint. The antero-inferior capsulolabral complex, comprising of the anterior inferior glenohumeral ligament, antero-inferior labrum and inferior capsule, acts as the main restraint to anterior dislocation when the arm is in a position of abduction and external rotation. Thus it is this complex that is most vulnerable to damage in anterior dislocations. Most commonly there is a detachment of the complex from the rim of the glenoid as a result of the forward translation of the humeral head, this being found in 85e97% of shoulders after an initial dislocation.3,4 This is usually referred to as a Bankart lesion (Figure 3), although the injury pattern had previously been reported by others, such as Perthes.4 Sometimes a piece of bone from the glenoid rim is detached together with the Bankart lesion, termed a “bony Bankart”. The impaction of the dislocated humeral head against the rim of the antero-inferior glenoid can result in a postero-lateral humeral head defect (Figures 4 and 5). This was described as early as 1861 but Hill and Sachs published a review of the available information on the lesion in 1940, since when it has carried their names.5 Other lesions that can occur include avulsion of the inferior glenohumeral ligament from its attachment to the
Figure 2 Radiograph (axial view) showing an anterior dislocation and a HilleSachs lesion.
glenoid labrum and the glenohumeral ligaments and capsule. The capsule and ligaments are lax through most of the range of motion of the shoulder, becoming taut at the end of range and acting as “check-reins”. Dynamic restraint is provided by the rotator cuff tendons and muscles (supraspinatus, infraspinatus, teres minor and subscapularis), together with neuromuscular co-ordination with the scapulo-thoracic and scapulo-humeral muscles that maintains correct positioning of the glenoid with respect to the humeral head. The predominant mechanism centering the humeral head in the glenoid fossa is concavity-compression, provided by the action of the rotator cuff and deltoid muscles compressing the humeral head into the concavity of the glenoid. The concavity of the glenoid is deepened by the labrum (a rim of mainly fibrous tissue) and the differential thickness of articular cartilage, which is thicker at the periphery of the glenoid than at its centre. Other mechanisms that contribute to the stability of the joint are the adhesion/ cohesion effect between the lubricated articular cartilage surfaces and the negative intra-articular pressure, or “suction-cup” effect. Dislocation of the shoulder joint occurs when the force applied to the joint overcomes these restraints. Dislocations can be acute, presenting within a week or two of occurrence, or chronic, presenting later. Recurrent dislocations are those that occur in shoulders that have previously been dislocated. In traumatic dislocations, there is a clear history of trauma and injury. In atraumatic dislocations, the shoulder dislocates for the
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Figure 3 A Bankart tear. (Reproduced with kind permission of eORIF.com) 1 Torn anterior labrum. 2 Torn inferior labrum. 3 Glenoid. 4 Humeral head.
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artery forwards whilst it is tethered by the pectoralis minor muscle.9 This also presents a particular hazard in the management of chronic anterior dislocations in the elderly that have been left untreated for several months, when attempts at a closed reduction have resulted in up to 50% reported mortality.10 Suspected vascular injury should be treated as an emergency with intravenous access, blood cross-matching for transfusion and the involvement of a vascular surgeon. The incidence of neurological injury is also high, having been reported to occur in up to 45% of cases.11 The axillary nerve is affected most often because the displaced humeral head causes direct pressure and traction as the nerve crosses the anterior surface of the subscapularis muscle then courses posteriorly under its inferior border, close to the inferior joint capsule, to pass through the quadrilateral space. Typically, sensation is affected in the regimental badge area and the diagnosis can be confirmed by EMG studies at 3 or 4 weeks after injury. Recovery is to be expected after reduction, though may require observation for 3 months. Injuries associated with a posterior dislocation include posterior glenoid rim fractures, antero-medial humeral head compression fractures (reverse HilleSachs lesion) and lesser tuberosity avulsion fractures.
Figure 4 A reduced glenohumeral joint with a HilleSachs lesion evident on the posterior aspect of the humeral head.
humeral head rather than from the glenoid side; a HAGL lesion (Humeral Avulsion of the Glenohumeral Ligament).6 Associated tears of the rotator cuff tendons are seen with increasing patient age: they are rare under 20 years of age and the incidence rises to approximately 30% in those over 40 years and 80% in those over 60.7 Fractures of the greater tuberosity are seen more frequently in patients over 30 years of age.8 The true incidence of vascular injury is unknown but it occurs more commonly in the elderly, who have fragile axillary vessels. Vascular injury most often affects the second part of the axillary artery, as the anterior dislocation of the humeral head forces the
Assessment The initial assessment of shoulder dislocations should include a thorough history and examination, including clear documentation of the neurovascular status and specifying the sensory and motor function of the axillary, musculocutaneous, median, ulnar and radial nerves. The mechanism of injury should be determined. An injury sustained with the arm in abduction and external rotation suggests an anterior dislocation, whilst a history of an epileptic seizure or electric shock would suggest a posterior dislocation. An absence of significant trauma suggests either an atraumatic variant of dislocation or recurrence in a shoulder that has previously sustained significant structural damage. On examination, the patient with an acute dislocation is often in severe pain with marked muscle spasm. In the case of an anterior dislocation the humeral head is often palpable anteriorly and a hollow is visible beneath the acromion posteriorly and laterally. The prominence of the acromion posteriorly is sometimes mistaken by the patient for a posterior dislocation. The arm is held in slight apparent abduction due to medialization of the proximal humerus and both active and passive movements are greatly restricted due to pain. In posterior dislocations the humeral head is often impacted onto the posterior glenoid rim and there is no obvious clinical deformity. The literature is full of reports of missed diagnoses of posterior dislocation despite the classic features having been clearly described by Astley Cooper in 1839.12 These include the arm being held in adduction, external rotation limited to less than neutral (0 degrees), elevation of less than 90 degrees, posterior fullness, flattening of the shoulder contour anteriorly and prominence of the coracoid process. Radiological examination must include at least two orthogonal views. An AP radiograph of the shoulder in the plane of the scapula is easily obtained and should be accompanied by either a scapular lateral or axillary view. The axillary view is preferred,
Figure 5 CT scan showing a HilleSachs lesion on the posterior aspect of the left humeral head.
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as it is easier to interpret, but this requires that the patient’s arm be abducted, which is often not possible due to pain. A Velpeau axillary view can be obtained instead: the patient leans backwards by about 30 degrees over the X-ray cassette and the beam is directed from above. The radiographs are assessed to determine the direction and magnitude of humeral head dislocation and the presence of associated humeral, glenoid or scapular fractures. Special attention needs to be paid to exclude an undisplaced fracture of the surgical neck of the humerus that could otherwise be converted to a displaced fracture if a reduction were attempted by the unaware.13
sedation, regional or general anaesthesia. The intra-articular administration of local anaesthetic is an alternative that has been shown to be safe and effective.16 Posterior dislocations can be significantly impacted onto the posterior glenoid with substantial compression of a segment of the humeral head, locking the shoulder in a dislocated position. Only very gentle attempts should be made at closed reduction in the emergency department and only if there is sufficient analgesia for the patient to be relaxed, otherwise the humeral head can be easily fractured. We recommend that reduction of impacted posterior dislocations should be performed under general anaesthesia in the operating theatre with fluoroscopic control, with a low threshold for conversion to open reduction. Posterior dislocations in which 20% or less of the humeral articular surface is impacted are usually stable after reduction. If more of the articular surface is affected then the joint tends to be immediately unstable in any degree of internal rotation. For defects less than 40% of the articular surface, a McLaughlin procedure, or transfer of the lesser tuberosity into the defect, can stabilize the shoulder.17 If the defect is larger than 40% than a hemiarthroplasty may need to be performed, or an allograft used to fill the defect.18 A pre-reduction CT scan is very helpful in assessing the size of the defect and allows proper planning. Post-reduction radiographs in two views should be obtained to verify the reduction and confirm the absence of fractures that may have become displaced or occurred during the reduction itself. The neurovascular examination should be repeated. The integrity of the rotator cuff should be assessed by checking the strength of isometric external rotation and abduction, although this is not always possible due to pain.
Treatment Prompt reduction of the dislocation is necessary to minimize the effects of tissue stretch, compression of neurovascular structures and muscle spasm that increases with time. It should be performed as soon as possible once the initial assessment has been completed and radiographs have excluded associated fractures. If there is a surgical neck of humerus fracture then reduction should be performed in the operating theatre under general anaesthesia with fluoroscopic control by a surgeon competent to perform an open reduction and humeral fixation if required. Otherwise reduction can be attempted in the emergency department. The exception to this rule of thumb is isolated fractures of the greater tuberosity associated with an anterior dislocation, which usually return to a minimally displaced position once closed reduction has been performed. If they do not, then reduction and internal fixation can be scheduled. Numerous techniques have been described to achieve closed reduction of an anterior dislocation, from as long ago as the time of Hippocrates (460e377 BC). One Hippocratic method involves longitudinal traction on the arm while the physician’s foot is placed across the patient’s axilla, against the chest wall, to provide counter-traction. Alternatively, counter-traction can be provided by a sheet wrapped around the patient’s torso and held by an assistant standing contralateral to the dislocated side. Keeping the patient’s elbow flexed while applying traction to the arm relaxes the neurovascular structures and gentle rocking from internal to external rotation can help disimpact the humeral head from the glenoid rim. Kocher’s method relies on levering the humeral head around the glenoid rim while the humeral shaft is manoeuvred against the anterior thoracic wall and has been reported to result in complications including brachial plexus injury, vascular injury and fractures of the humerus.14 In the Milch technique the patient is supine and the arm is gently abducted and externally rotated while a thumb pushes the humeral head back into place, whilst the gravity method requires that the patient is positioned prone and increasing weights are suspended from the affected arm.15 The senior author’s favoured method is the gravity method with the arm in slight abduction using gentle traction provided by the surgeon. This provides an atraumatic method of reduction with minimal risk of displacement of any associated fractures. Whatever method is chosen it is essential that the patient is adequately analgesed to provide optimum muscle relaxation and to enable a gentle reduction to take place. Reduction immediately after dislocation has occurred may require only minimal analgesia, whilst reductions performed several hours after injury or later may require narcotics,
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Subsequent management The subsequent treatment of the dislocation is aimed at restoring function of the shoulder and decreasing the risk of recurrent instability. Young age at the time of the first anterior dislocation is associated with a high rate of recurrence. In a prospective study Hovelius et al. found a 33% recurrence rate in those under the age of 20, compared to 10% in the 30e 40-year-old group, although other authors have suggested a much higher recurrent instability rate, in some cases over 80%, in young, active males.19,20 The increased rate of recurrence in younger patients is partly due to the lesion that occurs at the time of dislocation: younger patients typically sustain Bankart lesions with capsulo-ligamentous stretching, which heals less successfully than the greater tuberosity fractures seen in older patients. Other factors that predispose to recurrent instability are the presence of a large HilleSachs defect, significant glenoid rim fracture, persistent displacement of an associated greater tuberosity fracture and subsequent participation in contact sports. Atraumatic dislocations are also prone to reoccur.3
Non-surgical treatment Non-surgical treatment is the conventional method of management after a successful closed reduction. This involves immobilization of the affected shoulder, generally for between 3 and 6 weeks. Immobilization allows pain from the acute injury to settle and was thought to provide an opportunity for the pathological lesions to heal, reducing the risk of recurrent dislocation. This
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does not stand up to scrutiny, however, considering the high rate of recurrent instability observed in young patients, whilst MRI studies suggest that in primary anterior shoulder dislocations, labral ligament lesions heal in an incorrect position if immobilized in internal rotation.21
movement, strength and confidence have been restored. Whether these programmes benefit patients is unclear, as the reported rate of recurrent instability is as high as 92% in young active patients despite undergoing rehabilitation programmes.20 However, others have shown a much lower rate of only around 20% in young active patients after they had undertaken a post-reduction strengthening programme.26
Immobilization in internal rotation Traditionally, immobilization of the shoulder has been achieved by placing the arm in a broad arm sling with the forearm resting across the torso, i.e. with the arm in a position of internal rotation. This method dates back to the time of Hippocrates and is not based on any scientific rationale per se but has come about due to its ease of application and comfort. Likewise, the ideal period that the immobilization should be continued for has not been ascertained. Hovelius et al. found no difference in redislocation rates between patients who were immobilized in internal rotation for 3e4 weeks, compared to those immobilized for 1 week, or for as long as the patient found benefit.22
Surgical treatment Recurrent instability of the shoulder is not only painful and distressing for the patient, but it can lead to loss of confidence in the shoulder and cessation of sporting activities, loss of income and post-traumatic osteoarthritis. The risk of developing osteoarthritis after a shoulder dislocation is 20 times higher than in a normal shoulder and the risk increases the higher the number of episodes of instability.27 Previously, only open surgical techniques were available to stabilize a shoulder and were reserved for patients with recurrent instability, rather than after a first dislocation, because of the associated morbidity and complications. The advent of arthroscopic techniques, with the advantage of day case surgery, less post-operative pain and stiffness, improved cosmesis and faster recovery has led many to propose that a primary stabilization should be performed in those at high risk of recurrence, eg young males involved in contact sports. There is growing evidence that primary arthroscopic stabilization in this high risk patient group significantly reduces the rate of recurrent instability compared to non-surgical treatment and gives a higher chance of returning to pre-injury level of activity and sport.1,28 However, although arthroscopic techniques are very effective at dealing with isolated Bankart lesions (Figure 6) they are more likely to fail in the presence of glenoid rim fractures and large HilleSachs defects and, as with any surgical procedure, there are potential associated complications.29 Therefore, the decision to perform a primary arthroscopic
Immobilization in external rotation For the Bankart lesion to heal anatomically after a dislocation there must be adequate tissue apposition, or coaptation, between the capsulolabral complex and the glenoid surface from which it has become detached. In a series of studies including a randomized controlled clinical trial, Itoi et al. showed that placing the arm in a position of external rotation tensions the subscapularis muscle and tendon across the front of the glenohumeral joint capsule and results in better coaptation; patients treated in this manner had a lower redislocation rate compared to those treated in the conventional manner.21,23 The concept that external rotation bracing may decrease the risk of redislocation is extremely attractive but there are several drawbacks. This method of immobilization involves the use of a relatively costly and cumbersome orthosis that patients find awkward, significantly reducing compliance rates. Also, it is not known how soon the bracing needs to be started after the time of injury to be effective, although in Itoi’s study a delay of only 2 days seemed to lessen its benefit. The amount of external rotation required has not been defined. The patients in Itoi’s studies were placed in 10 degrees of external rotation, whilst another study has suggested 30 degrees combined with 60 degrees of abduction.24 As is the case with internal rotation, the ideal duration of immobilization has not been ascertained. Furthermore, a different randomized controlled study by Finestone et al. found no statistical difference in the redislocation rates between patients treated by external rotation vs internal rotation.25 Therefore the use of external rotation bracing remains controversial. Rehabilitation The patient should be encouraged to keep the elbow, wrist and hand mobile during the period of shoulder immobilization. Once this is over a clinical review is arranged to assess the integrity of the rotator cuff and examine for persistent neurological dysfunction. It is usual practice to refer the patient for a physiotherapy programme in order to restore the range of motion, strength and function. Exercises should include rotator cuff strengthening to improve concavity-compression and scapular stability exercises. Swimming after 6 weeks helps strengthening and proprioceptive control of the shoulder. Return to sports is allowed at around 3 months following injury, once a full range of
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Figure 6 Arthroscopic photograph showing a Bankart repair. (Reproduced with kind permission of eORIF.com)
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10 Calvet J, Leroy M, Lacroix L. Luxations de l’epaule et lesions vasculaires. J Chir 1942; 58: 337e46. 11 Rowe CR. Prognosis in dislocations of the shoulder. J Bone Joint Surg Am 1956; 38-A: 957e77. 12 Cooper A. On the dislocation of the os humeri upon the dorsum scapula, and upon fractures near the shoulder joint. Guy’s Hosp Rep 1839; 4: 265e84. 13 Ranawat AS, DiFelice GS, Suk M, Lorich DG, Helfet DL. Iatrogenic propagation of anterior fracture-dislocations of the proximal humerus: case series and literature review with suggested guidelines for treatment and prevention. Am J Orthop 2007; 36: E133e137. 14 Kocher T. Eine neue Reductionsmethode fur Schulterverrenkung. Berlin Klin 1870; 7: 101e5. 15 Milch H. Treatment of dislocation of the shoulder. Surgery 1938; 3: 732e40. 16 Lippitt SB, Kennedy JP, Thompson TR. Intraarticular lidocaine versus intravenous analgesia in the reduction of dislocated shoulders. Orthop Trans 1992; 16: 230. 17 McLaughlin HL. Locked posterior subluxation of the shoulder: diagnosis and treatment. Surg Clin North Am 1963; 43: 1621e2. 18 Gerber C, Lambert SM. Allograft reconstruction of segmental defects of the humeral head for the treatment of chronic locked posterior dislocation of the shoulder. J Bone Joint Surg Am 1996; 78: 376e82. 19 Hovelius L, Augustini BG, Fredin H, Johansson O, Norlin R, Thorling J. Primary anterior dislocation of the shoulder in young patients. A ten-year prospective study. J Bone Joint Surg Am 1996; 78: 1677e84. 20 Arciero RA, Wheeler JH, Ryan JB, McBride JT. Arthroscopic Bankart repair versus nonoperative treatment for acute, initial anterior shoulder dislocations. Am J Sports Med 1994; 22: 589e94. 21 Itoi E, Sashi R, Minagawa H, Shimizu T, Wakabayashi I, Sato K. Position of immobilization after dislocation of the glenohumeral joint: a study with use of magnetic resonance imaging. J Bone Joint Surg Am 2001; 83: 661e7. 22 Hovelius L, Eriksson K, Fredin H, et al. Recurrences after initial dislocation of the shoulder. Results of a prospective study of treatment. J Bone Joint Surg Am 1983; 65: 343e9. 23 Itoi E, Hatakeyama Y, Sato T, et al. Immobilization in external rotation after shoulder dislocation reduces the risk of recurrence. A randomized controlled trial. J Bone Joint Surg Am 2007; 89: 2124e31. 24 Hart WJ, Kelly CP. Arthroscopic observation of capsulolabral reduction after shoulder dislocation. J Shoulder Elbow Surg 2005; 14: 134e7. 25 Finestone A, Milgrom C, Radeva-Petrova DR, et al. Bracing in external rotation for traumatic anterior dislocation of the shoulder. J Bone Joint Surg Br 2009; 91: 918e21. 26 Aronen JG, Regan K. Decreasing the incidence of recurrence of first time anterior shoulder dislocations with rehabilitation. Am J Sports Med 1984; 12: 283e91. 27 Brophy RH, Marx RG. Osteoarthritis following shoulder instability. Clin Sports Med 2005; 24: 47e56. 28 Robinson CM, Jenkins PJ, White TO, Ker A, Will E. Primary arthroscopic stabilization for a first-time anterior dislocation of the shoulder. A randomized, double-blind trial. J Bone Joint Surg Am 2008; 90: 708e21. 29 Balg F, Boileau P. The instability severity index score. A simple pre-operative score to select patients for arthroscopic or open shoulder stabilisation. J Bone Joint Surg Br 2007; 89: 1470e7. 30 Chong M, Karataglis D, Learmonth D. Survey of the management of acute traumatic first-time anterior shoulder dislocation among trauma clinicians in the UK. Ann R Coll Surg Engl 2006; 88: 454e8.
stabilization should be made on a case-by-case basis in conjunction with the patient.
Current practice Chong et al. discussed the current methods of treatment by trauma clinicians, in England, for acute anterior shoulder dislocations.30 They reported that a standard management protocol is still not present and there are no standard guidelines for the management of anterior shoulder dislocation. Of the 90 clinicians involved in the study (orthopaedic surgeons, accident and emergency consultants and consultant anaesthetists) only 22 said they used a local protocol. The study demonstrated that 81% preferred conservative treatment for young athletic patients versus 19% who would recommend surgical intervention. 97% of clinicians would chose the conservative method of treatment for middle aged and elderly patients. Immobilization in a position of internal rotation was preferred by 93% of clinicians.
Conclusion In summary, the shoulder is the most commonly dislocated joint in the human body and anterior dislocations are the most frequent. Prompt, thorough assessment is mandatory before any attempt at reduction. Most dislocations can be treated by closed reduction although open surgery is occasionally required. Postreduction treatment is directed at reducing the incidence of recurrent instability. Non-surgical management is acceptable in the majority of cases and bracing in external rotation may be of benefit if applied early. There is a current trend towards offering primary arthroscopic stabilization to young patients at high risk of recurrent instability. A
REFERENCES 1 Kirkley A, Werstine R, Ratjek A, Griffin S. Prospective randomized clinical trial comparing the effectiveness of immediate arthroscopic stabilization versus immobilization and rehabilitation in first traumatic anterior dislocations of the shoulder: long-term evaluation. Arthroscopy 2005; 21: 55e63. 2 Hovelius L. Incidence of shoulder dislocation in Sweden. Clin Orthop 1982; 166: 127e31. 3 Johnson SM, Robinson CM. Shoulder instability in patients with joint hyperlaxity. J Bone Joint Surg Am 2010; 92: 1545e57. 4 Bankart Blundell A. The pathology and treatment of recurrent dislocation of the shoulder-joint. Br J Surg 1938; 26: 23e9. 5 Hill HAS. The grooved defect of the humeral head: a frequently unrecognized complication of dislocations of the shoulder joint. Radiology 1940; 35: 690e700. 6 Wolf EM, Cheng JC, Dickson K. Humeral avulsion of glenohumeral ligaments as a cause of anterior shoulder instability. Arthroscopy 1995; 11: 600e7. 7 Neviaser RJ, Neviaser TJ, Neviaser JS. Anterior dislocation of the shoulder and rotator cuff rupture. Clin Orthop Relat Res 1993; 291: 103e6. 8 Hovelius L. Anterior dislocation of the shoulder in teen-agers and young adults. Five-year prognosis. J Bone Joint Surg Am 1987; 69: 393e9. 9 Milton GW. The circumflex nerve and dislocation of the shoulder. Br J Phys Med 1954; 17: 136e8.
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Radiology quiz Questions
Case 2 A 7-year-old male was admitted with 2 months history of fever. He also complained of right hip pain preceded by minor trauma. His mother complained that he also had protruding eyes. What is seen on the radiographs (Figure 2 a and b). What are the differential diagnoses?
Case 1 A 9-year-old boy with previous history of anaemia and recurrent fractures, presented with a few months history of tingling and numbness involving the right hand and foot. Cervical spine and foot X-rays are shown (Figure 1a and b). What is the appearance of the bone known as? What are the differential diagnoses and the associated common complications?
Figure 1
Ajay Sahu Specialist Registrar, Department of Radiology, Derriford Hospital, Plymouth, UK. Figure 2
Nanda Venkatanarasimha Specialist Registrar, Department of Radiology, Derriford Hospital, Plymouth, UK. Priya Suresh Consultant Musculoskeletal Radiologist, Department of Radiology, Derriford Hospital, Plymouth, UK.
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Case 3 A 42-year-old obese female presented to the outpatient clinic with lower back pain radiating to both legs. There was no history of trauma. What finding on the plain radiograph is most responsible for her symptoms (Figure 3)? What is the next most appropriate imaging?
Case 4 A 66-year-old female presented with right hip pain of a few weeks duration and no history of trauma. Relevant past medical history included metastatic cervical cancer treated with radiotherapy. What features on the radiograph may explain the symptoms (Figure 4a)? What can be seen on the MR images (Figure 4bed)? What are the causes of the appearances in the sacrum?
Figure 3
Figure 4
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Case 5 An 82-year-old male was admitted to the emergency department with history of a minor fall. Pelvic radiograph with a left lateral hip view (Figure 5a and b) showed no fractures. He continued to have difficulty in weight bearing and still complained of hip pain. What would you do next?
Case 6 A 16-year-old boy fell from his horse onto his outstretched hand and presented to the emergency department with a painful deformed wrist. What are the X-ray findings and what would be the next appropriate investigation? What are the management options (Figure 6)?
Figure 6
Figure 5
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Answers
The diagnosis is multifocal Langerhans cell histiocytosis (eosinophilic granulomas). Patients commonly present with painful bone swelling. The skull is most frequently affected, followed by the long bones of the upper extremities and flat bones. Sometimes, osteolytic lesions can lead to pathological fractures. Peripheral blood testing is usually negative with normal inflammatory markers. Langerhans cell histiocytosis is a slowly progressing disease characterized by proliferation of Langerhans cells in various bones, skin, lungs or stomach. The multifocal disease is seen mostly in children and is characterized by fever, bone lesions and diffuse eruptions, usually on the scalp and in the ear canals. In about half of the cases, it involves the pituitary stalk leading to diabetes insipidus. The triad of diabetes insipidus, exophthalmos and lytic bone lesions is known as the HandeSchullereChristian disease. The differential diagnoses of a solitary osteolytic lesion with such appearances include brown tumour, simple bone cyst, leukaemia, lymphoma, metastasis and fibrous dysplasia.
Case 1 The cervical spine and foot X-rays show sclerotic bones with ‘typical bone with in bone appearance’. The appearance of these vertebrae is also described as “sandwich” vertebrae or “hamburger” vertebra (arrowhead Figure 7a). The foot radiographs demonstrate cortical thickening with medullary encroachment (arrowhead Figure 7b). There is diffuse osteosclerosis i.e. generalized dense amorphous structure-less bones with obliteration of the normal trabecular pattern. The diagnosis is osteopetrosis. Usually 50% of the patients remain asymptomatic and others may present with recurrent fractures and mild anaemia. Occasionally cranial nerve palsy occurs due to skull base foraminal narrowing by osteosclerosis. The sclerotic vertebral endplates alternate with the radiolucent regions of the disc spaces and the midportions of the vertebral bodies, resulting in a “ruggerjersey” spine. These patients can demonstrate metaphyseal expansion involving the long tubular bones resulting in Erlenmeyer flask deformity. The brittle bones are prone to fractures and marrow obliteration can result in anaemia with compensatory extramedullary haematopoiesis. The differential diagnosis includes heavy metal poisoning, hypervitaminosis D, melorheostosis, pyknodysostosis and fibrous dysplasia.
Figure 7
Case 2 The lateral X-ray of the skull demonstrates a lytic lesion with bevelled edges (arrowhead Figure 8a). The femoral radiograph demonstrates a lucent lesion with endosteal scalloping involving the proximal femoral metaphysis (arrowhead Figure 8b).
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Figure 8
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Case 3 The lateral radiograph demonstrates Grade II spondylolisthesis at L5/S1 with associated marked degenerative changes (arrowhead Figure 9a). The options for further radiological investigation include an oblique lumbo-sacral spine radiograph, CT or MRI scan to assess further. As this patient had symptoms indicative of radiculopathy an MRI of the lumbo-sacral spine was done. MRI shows bilateral pars defects of the L5 vertebrae with Grade II spondylolisthesis at L5/S1 and bilateral exiting neural foraminal stenosis causing compression of both the exiting L5 nerve roots (arrowhead Figure 9bed).
Pars defect is the defect in the pars interarticularis which is the weakest portion of the spinal unit, and lies between the superior and inferior articulating processes. The incidence varies from 3% to 7% of the population and increases with age. If it is unilateral, then it can lead to reactive sclerosis and bony hypertrophy of the contralateral pedicle and lamina due to stress changes, also known as Wilkinson syndrome. The oblique radiograph can show the pars defect as a radiolucent band and sclerotic margin resembling the collar of the “scottie dog”. A hereditary hypoplasia of the pars can lead to insufficiency fractures; pars defects are reported to occur in 34% of Eskimos.
Figure 9
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Case 4 The plain radiograph of the pelvis shows subtle features of right sacral fracture as indicated by interruptions of the horizontal sacral lines (arrowhead Figure 10a). The left side appears normal. On the MRI images (arrowhead Figure 10bed), there is evidence of intense marrow oedema seen along the sacral ala on both the right and left side, with more extensive changes on the right side. There is also a low signal intensity linear line identified around the sacral ala on the left. In Figure 10d, the STIR image clearly shows high signal change in both sacral alae. These features are consistent with an insufficiency fracture. MRI is highly sensitive for the detection of insufficiency fractures affecting the sacrum and pelvic ring. The finding
of intra-fracture fluid is described as a supporting feature for insufficiency fractures. Bone scans can show a symmetric area of increased uptake of radionuclide in an ‘H’ shaped configuration also referred to as the ‘Honda’ sign. These fractures result when normal physiologic stress is applied to bone with abnormal elastic resistance or deficient mineralization. A marked increase in insufficiency fractures occurs after radiotherapy, especially in postmenopausal patients as seen in this case. Other causes include rheumatoid arthritis, osteomalacia, Paget’s disease, hyperparathyroidism, renal osteodystrophy and steroid-induced osteopaenia. The common locations include lower extremity, sacrum, ilium and pubic bone.
Figure 10
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Case 5 The plain X-ray of the left hip did not show any fracture (Figure 11a and b). An MRI scan of the hip is the modality of choice to exclude an occult fracture of the neck of femur. Coronal and axial T1 and STIR sequences were performed (Figure 11cee). It demonstrates an undisplaced subcapital fractured neck of the femur. This was associated with bone marrow oedema and joint effusion. Hip fractures are a common occurrence especially in elderly people following a fall. The reported incidence of occult femoral neck fractures on plain radiographs is approximately 4%. When plain radiographs are negative,
and there is a high index of suspicion, further imaging with CT scan, bone scan or MRI scan may be very useful. However, there have been reported cases of a negative bone scan in a fractured neck of femur and false positive results due to ligamentous avulsion and periosteal injury. CT scan has also been reported to miss occult fracture. MRI has been shown to be sensitive and specific in the diagnosis of occult femoral fractures. Studies have shown that in radiographic negative cases, where clinical concern is high, MRI showed femoral neck fractures in 23e50%. It has been demonstrated that the MRI is very useful in making the definitive diagnosis in patients with occult fractures of the pelvic ring and neck of femur.
Figure 11
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Case 6 There is widening of the scapholunate joint on the AP view, with a triangular appearance of the lunate (arrowhead Figure 12a and b). The lateral view shows that the capitate is lying posterior leaving an empty lunate articular surface. The diagnosis is trans-scaphoid perilunate dislocation. The next radiological investigation of choice is a CT scan. The CT images confirm that the trans-scaphoid perilunate fracture dislocation has been reduced but there are associated fractures of the proximal pole of the scaphoid and
fracture of the volar aspect, of the triquetrum (arrowhead Figure 12cee). Screw fixation of the scaphoid and triquetral fractures is shown (arrowhead Figure 12f). The common mechanism for wrist dislocation is fall onto the outstretched hand and its incidence is around 10% of all carpal injuries. Perilunate dislocations are two to three times more common than lunate dislocation and they are accompanied by fracture in 75% (trans-scaphoid perilunate dislocation). The most common is dorsal dislocation as shown in this case.
Figure 12
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Physeal fractures: basic science, assessment and acute management
Basic science Bone development During foetal development, the long bones are initially formed as cartilage templates consisting of organized chondrocytes bound by perichondrium. As development continues, mesenchymal cells condense within this template, perichondrium is replaced with periosteum, blood vessels establish a supply into the bone and ossification begins at the primary ossification centre. Endochondral ossification is responsible for the growth of long bones, and is also seen in fracture healing.
Emily R Dodwell Simon P Kelley
Abstract
Macroscopic anatomy During the course of childhood, bones grow in both width and length. There is often confusion in the terminology of skeletally immature bones. The term “physis” comes from the latin for growth.8 The physis is made of cartilage and is the anatomical region responsible for longitudinal and circumferential growth of bone. The physis is also sometimes referred to as the growth plate, the epiphyseal plate, the epiphyseal growth plate, or the metaphyseal physis. The term metaphyseal physis is used to distinguish this cartilage from the growth cartilage of the epiphysis, which is sometimes referred to as the articular physis,9 or secondary physis.8 Secondary ossification centres develop within the epiphysis and enlarge spherically by endochondral ossification until they encompass the entire space of the pre-existing epiphyseal cartilage. In long, or tubular, bones there is a primary growth centre located in the diaphyseal region. Long bones have one or more secondary ossification centres at both ends. The secondary ossification centres are in the epiphysis. The region where the primary and secondary ossification centres meet is the physis as seen in Figure 1. The physis is connected to the epiphysis and metaphysis by the zone of Ranvier and the perichondral ring of LaCroix. The zone of Ranvier is wedge-shaped and contains germinal cells that are continuous with the physis proper. Whilst the physis itself is responsible for longitudinal growth, the zone of Ranvier contributes primarily to circumferential growth. Osteoblasts, chondroblasts, and fibroblasts make up the zone of Ranvier. The bony component of the perichondral ring is contributed by osteoblasts, the chondroblasts are responsible for growth, and the fibroblasts circumferentially surround the zone and attach it to the perichondrium adjacent to the physis. The perichondral ring of LaCroix is fibrous in nature and is in continuity with the fibrous region of the zone of Ranvier and with the periosteum. A number of human bones have a secondary ossification centre only at one end. The phalanges, the first metacarpal and metatarsal do not have secondary ossification centres distally. The second through to the fifth metacarpals and metatarsals do not have secondary ossification centres proximally. The clavicles and ribs similarly have secondary ossification centres only at one end. Despite the lack of secondary ossification centres at both ends of these bones, a number of studies report that growth still does occur at both ends.10,11 However, other reports suggest that longitudinal growth only occurs at the site of the secondary ossification centre.12 Some long bones, such as the humerus, have multiple secondary ossification centres at both ends. In some instances, such as in the proximal femoral epiphysis, the secondary ossification centre starts
Physeal fractures account for approximately one-third of all paediatric fractures. Although many of these injuries heal without negative sequelae, this fracture type is at risk of partial or complete growth arrest. The anatomy of the physis, and the basic science behind its growth and function are presented. We also present the epidemiology of physeal fractures, as well as outcomes following physeal injuries at various locations. General guidelines for treatment are discussed. A thorough understanding of the basic science, epidemiology, and treatment options for physeal fractures may help the clinician optimize management for children with this type of injury.
Keywords fracture; paediatric; physeal; SaltereHarris
Introduction Fractures involving the physis account for up to one-third of paediatric fractures. Due to the unique anatomy of the immature skeleton, and the risk of partial or complete growth arrest, extra care must be taken in assessing and treating patients with injuries of this type. In this review, we present the basic science, assessment and treatment of acute physeal injuries.
Epidemiology Childhood fractures are common, with 27% of girls and 42% of boys sustaining a fracture in childhood.1 The incidence of paediatric fractures varies by report, and is from 13312 to 3610/ 100,000 person years.3 The incidence of physeal fractures is 279.2/100,000 person years.4 Physeal injuries complicate 185,6e 30%7 of paediatric fractures. Of those fractures involving the physis, growth arrest occurs in 5e10% of cases. The incidence of growth arrest, however is quite variable depending on physeal location, pattern of injury, method of treatment, as well as numerous patient factors.
Emily R Dodwell MD MPH FRCSC Paediatric Orthopaedic Fellow, Department of Orthopedic Surgery, The Hospital for Sick Children, 555 University Ave, University of Toronto, Toronto, ON, Canada. Conflict of interest: none. Simon P Kelley MBChB FRCS (Tr and Orth) Paediatric Orthopaedic Surgeon, Department of Orthopedic Surgery, The Hospital for Sick Children, 555 University Ave. Assistant Professor, Department of Surgery, University of Toronto, Toronto, ON, Canada. Conflict of interest: none.
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Epiphyseal artery
Resting zone-------------------Zone of differentiation------Proliferative zone-------------Hypertrophic zone Zone of provisional calcification Vascular invasion
Zone of Ranvier
Metaphyseal artery
Periosteal artery
Intramedullary artery Figure 1 Schematic showing zones and vascular supply to the physis (with kind permission from Springer Science þ Business Media: Epiphyseal Growth Plate Fractures, chapter 2, 2007, page 8, Peterson, H.A, Figure 2.2).
as one and splits into two. Flat bones can have multiple primary and secondary ossification centres. In contrast to epiphyses which articulate with neighbouring bones, and whose physes are responsible for longitudinal growth and are aligned perpendicular to the longitudinal axis of the bone, an apophysis is usually oblique to the axis of the bone, is not responsible for longitudinal growth and does not articulate with another surface. Epiphyses typically do not have musculotendinous attachments, and are sometimes referred to as “pressure epiphyses”. Apophyses on the other hand do have ligamentous or tendinous attachments, and are often referred to as “traction epiphyses”. Apophyses often contribute to circumferential growth, or to the growth of the process of which they are a part.
contribute significantly to longitudinal growth. The blood supply to this region is from terminal branches of the epiphyseal artery. The contiguous zone is called the zone of differentiation, in which there is a single germinal cell layer. In this zone cells divide, differentiate and orientate into columns. These cells also produce matrix, composed of matrix vesicles and collagen fibrils. The third zone is the zone of proliferation, where chondrocytes
Resting Zone
Zone of Differentiation
Microscopic anatomy The architecture of the physis has classically been depicted as columns of chondrocytes, in various stages of maturity and bony transformation, aligned with the longitudinal axis of the bone. The layers of the physis are typically described with reference to the secondary ossification centre and are divided into five zones of chondrocytes within an extracellular matrix, as seen in Figure 2. These descriptive zones assist in the understanding of physeal structure and function, but the separations of the zones are indistinct and there is a continuum of cell morphology and function. The layer of cartilage closest to the secondary ossification centre is called the reserve, resting or germinal zone. Cells in this zone are typically irregular in shape and are responsible for storing nutrients. There is an accumulation of stem cells in this region. Cell division in this zone is sporadic and does not
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Zone of Proliferation
Zone of Hypertrophy
Zone of Provisional Calcification
Figure 2 Photomicrograph of the physis (image reproduced with kind permission from S. Karger AG, Basel from Farnum et al. Cell Tissues Organs. 2000. 167:247).
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rapidly increase in number. The first three zones of the physis are sensitive to trauma, and injury here can have serious consequences to future growth. Frequently the zones of differentiation and proliferation are referred to as a single zone, however it is conceptually useful to divide them based on the quite distinct processes of differentiation and proliferation. Terminal branches of the epiphyseal artery do not extend beyond the row of germinal cells in the zone of differentiation. Nutrients and oxygen to more distant regions of the physis are delivered by diffusion. The reserve, differentiation and proliferative zones contain considerably more matrix than the other regions. The strength of the physis is primarily determined by the quantity and quality of the matrix.13 Thus, the first three layers are relatively strong and particularly resistant to shear forces. The fourth zone is that of hypertrophy. This is an avascular region in which cells are primarily responsible for the elongation of bone. These cells enlarge by cytoplasmic and nuclear swelling. Cells can increase 10-fold in size. These cells demonstrate greater metabolic activity and follow a path of programmed cell death, or apoptosis. The columnar configuration continues in this region, cells having increased height but less extracellular matrix. This relative lack of matrix makes this zone particularly susceptible to shear forces. In the following zone of provisional calcification or endochondral ossification, vascular channels invade between the dead and dying chondrocytes, and the matrix becomes mineralized. The mineralization provides increased resistance to shear, such that the hypertrophic zone is a region of relative weakness sandwiched between areas of higher mechanical integrity. This zone of provisional calcification abuts the metaphysis, is invaded by osteoblasts and other osteoprogenitor cells, and is eventually replaced by bone.
Figure 3 Schematic showing Dale and Harris type A and B blood supplies to the epiphysis.
radial head. In type A configurations, with the epiphyseal artery in close juxtaposition to the physis, physeal disruption is more likely to injure the epiphyseal blood supply. This “at risk” configuration of the vascular supply contributes to the higher rate of avascular necrosis (AVN) associated with physeal fractures in these locations.
Control of growth Physeal growth is controlled by both local and systemic factors. General health, nutrition, genetic factors, blood supply, trauma, infection, and localized stresses can all influence growth. Peptides, proteins, and hormones mediate signalling to the growth plate.12 Leptin, insulin-like growth factor (IGF), vitamin D and metabolites, parathyroid hormone-related protein (PTHrP), thyroid hormone (T3), growth hormone (GH), sex steroids and glucocorticoids have all been shown to influence physeal growth. These factors can directly influence the physeal chondrocytes, but in many instances also have modifying effects on other physeal signalling pathways. These systemic hormones frequently exert their action by causing physeal chondrocytes and perichondrocytes to express additional factors, which work in autocrine or paracrine fashions. These include fibroblast growth factors (FGF), Indian hedgehog (IHH), bone morphogenetic protein (BMP), transforming growth factor-beta (TGF-beta), and vascular endothelial growth factor (VEGF). The three major signalling loops are PTHrP-IHH, BMP-FGF, and GH-leptin-IGF. IHH is primarily expressed by mature prehypertrophic and hypertrophic chondrocytes. When IHH binds to its receptor, a number of downstream target genes are triggered, including BMPs. IHH also instigates the expression of PTHrP. PTHrP is synthesized by periarticular and perichondral cells. PTHrP is responsible for proliferation of chondrocytes in the resting and proliferative zones, slowing down differentiation into hypertrophic chondrocytes. In addition to generating negative feedback by limiting the differentiation of the chondrocytes, PTHrP also acts on osteoblasts and osteoclasts in the calcifying zone, thus also enhancing bone formation and remodelling the newly constructed metaphysis. Hypertrophic chondrocytes down-regulate IHH, through which PTHrP is decreased, thus removing a major inhibitor of chondrocyte differentiation, which allows terminal differentiation of the hypertrophic chondrocyte. Overall, PTHrP is believed to be a powerful driver of chondrocyte proliferation, and IHH is a strong inhibitor of chondrocyte maturation. Excess PTHrP causes massive over-production in the proliferative zone. In the
Blood supply The blood supply to the physis originates from three sources. There are epiphyseal arteries, intramedullary metaphyseal arteries, and periosteal arteries in the circumferential region of the zone of Ranvier. In the pre-natal and early post-natal period, vessels have been shown to cross the physis. However, in normally developed physes, vessels do not cross from the metaphyseal side into the epiphysis. Metaphyseal vessels form loops that end in the hypertrophic zone in which chondrocytes begin their journey towards programmed cell death. Osteoprogenitor cells obtain their nutrients from these vessels and form new bone, primary spongiosa bone, on the cartilage scaffold. The epiphyseal arteries penetrate the epiphysis and branches of these arteries and supply nutrients to the germinal and proliferating zones. The periosteal artery supplies the zone of Ranvier. In their classic study of mammalian epiphyseal blood supply, Dale and Harris,14 designated two distinct epiphyseal blood supplies based on the anatomy of the epiphyseal artery. In the type A configuration, the epiphysis is almost entirely covered with articular cartilage, and the epiphyseal artery traverses the perichondral region, adjacent to the physis, before entering the epiphysis. In the type B configuration, there are areas of the epiphysis not covered by articular cartilage. The epiphyseal artery then enters more directly from the epiphyseal side, as seen in Figure 3. The type A configuration of the epiphyseal artery is uncommon, examples being found in the proximal femur and the
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Determining remaining growth
absence of PTHrP, the columns of proliferating chondrocytes are atypical or absent. Mutations in the receptor for PTHrP are linked to Jansen’s chondro-osteodystrophy. FGF is a heparin-binding protein that plays an integral role in mesenchymal condensation and the formation of limbs. There are 22 isoforms in humans, which bind to FGF receptors 1e5. FGFR-3 is the most prolific; it is a negative regulator of chondrocyte proliferation and thus plays a major positive role in the terminal differentiation of chondrocytes into their hypertrophic state. The effect of FGFR-3 is most commonly seen clinically in achondroplasia, wherein a mutation causes persistent ligandindependent activation of FGFR-3. This effectively inhibits the maturation of chondrocytes and thus reduces longitudinal bone growth, as is characteristic in this skeletal dysplasia. Similarly BMP is required for terminal differentiation of the chondrocyte into it’s hypertrophic state. BMPs 1e7 are most concentrated in the hypertrophic zone. BMP receptors are located throughout the growth plate and in the perichondrium. Inhibitors of BMP are also distributed throughout the physis. These include fibrillins, heparin sulphate proteoglycans, gremlin, chordin and inhibitory Smads 6 and 7. Low levels of BMP in the resting zone are thought to be responsible for the relatively low rates of cell division and metabolism in this region. Overall, BMP promotes proliferation and FGF inhibits proliferation whilst upregulating the transition into the hypertrophic state. Growth hormone is produced in the pituitary gland and acts on all zones of the physis. It is mediated by insulin-like growth factor, which is produced in both the liver and in the proliferating and hypertrophic chondrocytes of the physes. IGF-1 causes increased activity in the proliferating zone. In the absence of IGF-1/GH, proportionate short stature results, while excess GH causes gigantism. Thyroid hormone acts directly on the physis by recruiting chondrocytes in the resting zone, facilitating transition into proliferating chondrocytes and stimulating differentiation. Thyroid hormone also acts indirectly by stimulating GH secretion, thus acting through the GH-IGF-1 pathway. Leptin regulates satiety and energy and influences the activity of GH and IGF-1. It is produced by hypertrophic chondrocytes and leptin receptors are present locally within the physis. Leptin causes proliferation of chondrocytes, expression of collagen types II and X, and activity of IGF-1 and TGF-beta. Leptin also stimulates osteoblast proliferation and enhances osteoprogenitor cell maturation. As leptin levels increase with obesity, bone is increased to correspond with the additional load. VEGF regulates angiogenesis, affecting the ingrowth of vasculature from the metaphysis into the physis. A number of matrix metalloproteinases have also been shown to play significant roles in promoting angiogenesis at the physis. Chondromodulin inhibits angiogenesis, as do thrombospondins-1 and -2, and a number of metalloproteinase inhibitors. Glucocorticoids strongly inhibit growth by decreasing the rate of proliferation of cells and the height of these cells by increasing the rate of apoptosis in the hypertrophic zone, and by inhibition of vascularization through restriction of VEGF. TGF-beta inhibits hypertrophy and differentiation in the physis; it is most active in the hypertrophic zone. Connective tissue growth factor (CTGF) is also primarily expressed in the hypertrophic zone and similarly plays a role in chondrocyte proliferation and physeal angiogenesis.
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The timing of physeal closure varies with the physeal location, age, ethnicity, sex and numerous other factors. Knowledge of rate of growth and likely age at closure can help the clinician determine the expected angular deformity or limb length discrepancy if a partial or complete growth arrest occurs following a physeal fracture. There are a number of methods available to determine projected limb length discrepancies. Some of the most frequently used include the AndersoneGreeneMesner growth remaining charts, the Menelaus-White method, the Moseley straight line graph and the Paley multiplier method. Methods are generally based on bone age, not chronologic age. Bone age can be determined with reference to Greulich and Pyle’s atlas of hand radiographs. In this technique one matches characteristic features, such as the appearance of sesamoids and the closure of particular physes, to radiographs within the atlas with assigned ages. The technique of Sauvegrain is becoming increasingly popular. In this technique, four anatomical landmarks are used to determine the skeletal maturity of the child. These include the lateral condyle, the trochlea, the olecranon and the proximal radius. A score is given for each anatomic site, and these are then combined, with the maximum score being 27 at skeletal maturity. A graph can then be used to determine bone age based on association with the Sauvegrain score, as seen in Figure 4.15 Anderson, Green and Mesner performed radiographic examinations of children’s femurs and tibiae on a yearly basis to determine the mean length of each bone segment for each year of life, based on bone age. They published separate charts of growth remaining for boys and girls. The Menelaus method uses a modified White technique to estimate remaining growth. White had postulated that the femur grew 3/8 inch and the tibia 1/4 inch per year, with growth completion at 17 for boys and 16 for girls. Menelaus modified the estimation rule by changing the expected completion of growth to 16 for boys and 14 for girls. In predicting leg length discrepancies, he reported that calculations were within a 1/2 inch of the true length discrepancy 89.6% of the time using the Green and Anderson technique, and 80% of the time using his technique. Estimates of yearly growth provide a rough method of length discrepancies for long bones of the upper and lower extremities, as seen in Figure 5, which also includes proportions of growth from each physeal location. In the femur, 30% of the growth occurs at the proximal end, and 70% at the distal end. In the tibia, 60% is proximal and 40% is distal, while in the fibula the majority of the growth is from the distal end. In the humerus, 80% of growth is from the proximal end, and 20% of growth occurs distally. In the radius and ulna, approximately 20% occurs proximally, with the remaining 80% being from the distal end.16 The Moseley straight line graph can be used to determine the timing of epiphysiodesis for the long leg in treating leg length discrepancy. The graphs are based on the data published by Anderson Mesner and Green. This graphic technique incorporates calculations of skeletal maturity based on hand/wrist radiographs, growth inhibition and relative size. Comparing his technique to that of Anderson Green and Mesner, he found that his technique had a mean error of 0.6 cm, while that of Anderson Green and Mesner was 0.9 cm.
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Paley et al17 developed the multiplier method, using data from a number of leg length databases. Provided that there is constant growth inhibition, one can calculate the expected leg length discrepancy based on the current leg length discrepancy, and the multiplier for that age bracket and sex. General assessments of maturity can also be used to corroborate estimates made from radiographic investigations. Tanner staging makes use of the presence of secondary sexual characteristics to track progress through puberty. In addition to this, ascertaining the timing of onset of menses in girls can be helpful, as growth typically ceases 1e2 years after onset of menses.
Reaction to stress When physes are subjected to abnormal forces, fracture or crush injury can occur. Physes are most resistant to longitudinal compressive forces or traction, and most susceptible to torsion and shear injuries. When a musculoskeletal insult is inflicted, the injury typically occurs at the weakest area. While forces in adults might cause joint dislocations, or fracture to metaphyseal or diaphyseal bone, in children the injury often involves the physis. Periosteum has been found to increase the force required to separate the physis almost five-fold. The periosteum is stronger, thicker and less easily injured than it is in adults. Frequently a portion of this thick periosteum remains intact in paediatric fractures, and this can either be a barrier or benefit to fracture reduction. Fracture patterns are determined by the magnitude and direction of the applied force, as well as the location and maturity of the physis. Physes that are nearing closure will fracture differently to those that are fully open. Physes at different anatomical sites vary with respect to the number of interdigitations, mamillary processes or pegs that are present. The hypertrophic zone and zone of provisional calcification have less matrix, less mechanical stability and, as such, are at increased risk of fracture. The zone of calcification does gain some increased strength from the calcification, so fractures frequently occur through the hypertrophic zone or between the hypertrophic zone and the zone of provisional calcification. Although this is the classic anatomic site of physeal fracture, fractures can occur through other zones. It is also possible for fractures to pass through more than one zone of the physis, and extend into the metaphysis or epiphysis. Some physes, such as the distal radius, are quite consistent in shape. Due to the relative flatness of this physis, fractures tend to be isolated to the hypertrophic zone, do not damage the germinal matrix, and heal without incident. Physes such as those at the distal femur and distal tibia however, are more curved and undulating. Applied forces in this situation are more likely to pass through more than one zone of the physis, and injury to the germinal matrix is more common, leading to a much higher risk of growth disturbance in this region. Physeal fractures are more common during growth spurts for both males and females. During these periods of increased growth, cells divide more rapidly, there are more chondrocyte columns, column lengths are increased and there is increased size of each individual hypertrophied cell. Some reports suggest that thicker physes are more susceptible to fracture. However, the adolescent physes become thinner as they near skeletal maturity, yet this age group also have the highest rate of physeal injury. Probably the increased activity level and size of the adolescent overshadows the protective effect of having a thinner physis at this age.
Figure 4 The Sauvegrain method of determining bone age (images reproduced with kind permission from Lippincott Williams & Wilkins from Lovell and Winter’s Pediatric Orthopedics, Morrissy R.T. and Weinstein, S.L. (Eds), 2005).
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Figure 5 Proportion of growth from each physis, and physeal mean growth per year (images reproduced with kind permission from Lippincott Williams & Wilkins from Lovell and Winter’s Pediatric Orthopedics, Morrissy R.T. and Weinstein, S.L. (Eds), 2005).
Classification
systems have been devised. A number of additional fracture patterns.23e25 have been reported, and others advocate subdivision of the SaltereHarris types to reflect specific fracture patterns such as high-energy injuries and comminution.26 One additional fracture type that is rare but often discussed was added by Rang, a colleague of Salter’s. This injury is termed a Rang VI or a SaltereHarris VI injury. It is not truly a fracture, but is an injury to the perichondral ring. It is usually the result of direct impact, and typically results in asymmetric growth arrest. The routine addition of this fracture type to the SaltereHarris classification system has not gained widespread use. Despite some debate regarding the optimal classification of physeal fractures, the classic five-type system of SaltereHarris has withstood the test of time.
A number of classification systems exist for physeal fractures. Prior to radiographs, classification could only be performed in patients with open fractures, traumatic amputations or fatal injuries. Soon after Roentgen’s discovery of radiographs in 1885, Poland published the first real classification system for physeal fractures.18 Other classification systems include those by Aitken, Bergenfeldt, Brashear, Ogden, Shapiro Peterson and CarothersCrenshaw. Currently, the most commonly used classification system is that of Salter and Harris (Figure 6), as described in their classic paper involving the epiphyseal plate.19 This system is anatomic, is easy to remember and in most cases helpful with planning treatment and prognostication. In type I fractures, the fracture line runs transversely through the physis. In type II fractures, the fracture line traverses through the physis and then exits on the metaphyseal side, typically forming a triangular Thurston-Holland fragment. In type III fractures, the fracture line traverses partially through the physis and then exits intra-articularly through the epiphysis. Type IV fractures involve a fracture line that passes both through the epiphysis and through the metaphysis. A type V fracture is a crush injury to the physis. This injury may radiographically appear similar to a type I injury, but the mechanism is of higher energy and is typically the result of axial loading of the bone. The germinal cells are injured by the crush and growth arrest is common. The SaltereHarris classification has traditionally been used to estimate prognosis and risk of growth arrest with an increasingly poor prognosis as one moves from type I to type V injuries,20 although lack of correlation has been demonstrated in a number of studies5,21e23 and some authors have questioned the existence of the type V fracture.8 As such, other classification
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Isolated epiphyseal fractures Although epiphyseal fractures in combination with injuries to the physis can be classified as type III and type IV fractures, isolated fractures of the epiphysis are not represented in the SaltereHarris system. In isolation, epiphyseal fractures can occur as avulsion injuries, or as crush or shear injuries that do not extend into the growth plate. Avulsion of the tibial spine is an example of a common intra-articular epiphyseal fracture. For both isolated articular injuries and those combined with injury to the physis itself, it is important to ensure appropriate reduction. Articular congruence is necessary, and the synovial fluid may inhibit healing of displaced fractures. Articular avulsion fractures may also inhibit joint range of motion or cause joint instability. Osteochondral fractures are another example of articular physeal injury. They are most common at the distal femur, patella, distal humerus and radial head. Undisplaced, stable fragments in patients with open physes may heal with activity modification and observation.
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healing typically involves an inflammatory phase and a reparative phase, but no remodelling phase. The physeal fracture gap is first filled with fibrin. The calcified tissue on the diaphyseal side of the physis remains, whilst growth continues from the epiphyseal side. This results in a significantly thicker physeal plate. Callus then grows from the metaphysis and periosteum, uniting the epiphysis with the diaphysis. Once this reunion occurs, the regular blood supply is reconstituted and the routine endochondral ossification of physeal growth is reinstated.30 Following physeal fracture, there may be complete healing with no long-term consequences to growth. Alternatively, partial or complete growth arrest may occur. Growth disturbance can be attributed to one of three possible scenarios, or a combination thereof. Growth can be slowed or arrested due to injury to the germinal layer, injury to the blood supply, or the formation of a bony bridge across the physis. Previously it was postulated that most fractures occurred through the hypertrophic zone. However, more recent accounts suggest that there is much more variability in the plane of the fracture line and that physeal fractures frequently pass through multiple zones.30 When physeal bars form, they do so by primary ossification, meaning that bone forms directly along vertical septa at the physealeepiphyseal border. There is some evidence that entrapped periosteum may predispose to bar formation, but other reports suggest that it leads only to minor shortening. Anatomical reduction lessens bar formation in type III and IV fractures and in some type II fractures. Regardless of fracture pattern or location, most physeal fractures heal rapidly, usually within 3 weeks.30 The grade of injury, the particular physis injured, the age of the child, the amount of growth remaining, and the location within the physis that the injury has occurred are important for determining risk of growth arrest. If the entire physis is injured, the length of the bone will be uniformly decreased. If there is an eccentric physeal injury that results in partial growth arrest, an angular deformity will result. As shown by Dale and Harris, vascular injury may be more common with type A epiphyses, such as in the proximal femur and proximal radius. The rate of AVN in proximal femoral physeal fractures (Delbet I proximal femoral fractures) is 38%.31 Older children are more likely to develop AVN. In general, the risk of AVN is related to the degree of displacement on initial radiographs,32 but this has not specifically been assessed in the paediatric population. Post-traumatic AVN of the proximal femur typically has a poor outcome. For patients under the age of 50 with post-traumatic AVN, the majority requires reconstructive hip surgery.33 In general the outcome following trauma-related AVN is worse than seen in idiopathic AVN (Perthes’ disease). In contrast to the high rate of AVN following trauma to the proximal femur, AVN following paediatric radial head fracture is actually quite rare.8 However, a high index of suspicion must be maintained, as avascular necrosis of the proximal radius may result in premature physeal closure or deformity.34 The fracture pattern can be helpful in prognosticating the risk of AVN in proximal radial physeal fractures. A physeal separation (displaced SaltereHarris I) would generally disrupt the epiphyseal vessels, while a SaltereHarris II fracture may keep the epiphyseal vessels intact due to a Thurston-Holland fragment and intact soft tissues protecting the epiphyseal vessels around the radial head.34
Figure 6 The SaltereHarris classification system (reprinted from Orthopaedics and Trauma, 24(1), Kelley, S., The response of children to trauma, Pages 29e41, Copyright 2010, with permission from Elsevier).
Healing, remodelling, and growth arrest Due to the potential for remaining growth, paediatric fractures have the ability to remodel considerably. Wolff’s law states that bone will adapt to the forces that it is subjected to, and will become stronger with exposure to both tension and compression.27 Bone is resorbed on the side where it is in excess, and is laid down on the side that it is deficient, resulting in a straighter bone. Of note, the Heuter Volkmann principle states that bone growth is stimulated by tension, and slowed by compression.28,29 This can be seen at the physis, in distraction osteogenesis, and in some pathological orthopaedic conditions. For example, the asymmetrical pressure on the medial physis in Blount’s disease is hypothesized to contribute to the progressive varus deformity observed in this condition. Asymmetric physeal growth in a healthy physis can also partially compensate for, or completely correct, angular long bone deformities. Physeal fractures do not heal with typical callus formation, as physeal healing involves the repair of cartilage not bone. Physeal
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Injury to the germinal layer may be more likely with type V crush injuries and injuries at irregular undulating physes, where a fracture line may pass through multiple zones. Risks for bar formation include fracture lines passing through bony segments of the epiphysis, and fractures that are malreduced. Anatomical reduction of type IV physeal fractures is particularly important, both for this reason, and to minimize articular congruence.
If stable, type I and II fractures can be immobilized in a cast or splint. Unstable fractures may require percutaneous or internal fixation. Type III and IV fractures frequently require open reduction and fixation, as these are intra-articular fractures and anatomical reduction is necessary. Occasionally periosteum or other soft tissues can be entrapped within the physis following a physeal fracture. Fractures irreducible by closed means also require open reduction. The principles for treating open physeal fractures should be the same as any other open fracture, typically requiring urgent irrigation and debridement prior to reduction and stabilization. However, recent retrospective series have shown acceptable outcomes for Gustillo grade 1 paediatric open fractures treated without formal irrigation and debridement in the operating theatre.35 At some centres, there is a trend to treat Gustillo grade 1 fractures with irrigation in the Emergency Department, followed by closed reduction and casting or splinting, provided that the fracture pattern permits this method of immobilization. This protocol must be tempered by consideration of the conditions under which the open fracture occurred, as a farmyard injury would more likely require a formal debridement and irrigation for an acceptable outcome than a relatively “clean” grade 1 open fracture occurring in the home. Antibiotic regimens vary for grade 1 fractures, but are considered an essential management strategy.
Assessment In addition to a standard history and physical examination, radiographs should be performed in at least two planes, such that the exact fracture pattern can be determined. If there is ambiguity in the fracture pattern additional views, such as oblique radiographs, may be obtained. In fractures that are reduced under conscious sedation or general anaesthetic, live fluoroscopy and arthrography for intra-articular fractures may be useful. CT or MRI may also be recruited in cases where radiographs are inadequate. CT and MRI are particularly useful for intra-articular injuries, as anatomical reduction is necessary, and complete understanding of the fracture pattern is typically required for pre-operative planning. Three-dimensional imaging is typically used in assessing the intra-articular steps and gaps of Tillaux and triplane fractures of the ankle. An understanding of timing of appearance of secondary ossification centres, and timing of physeal fusion at each anatomical location is essential for the appropriate diagnosis and treatment of these fractures. Approximate timing of these milestones for both boys and girls is presented in Table 1.
Fixation A number of fixation methods are possible for the treatment of physeal fractures. These include smooth K-wires, threaded Kwires, screws, and external fixators. The choice of implant is often not critical as long as one heeds the principles of treating physeal injuries. Plating is possible, but care should be taken to not disrupt the perichondral tissue when placing the plate and screws. If growth is to continue after healing, plates will need to be removed once the fracture is healed, otherwise they may act as a tension band or tether. Intramedullary nails, flexible or rigid, are generally discouraged in physeal fractures, as these by definition would be relatively large diameter prostheses crossing the physis. If fixation must cross the physis, smooth wires passing centrally through the physis have a low risk of growth disturbance. In contrast, smooth wires passing eccentrically have a higher rate of growth disturbance, and the effect of threaded wires and screws passing across the physis have been likened to the results of physeal stapling.36 Examples of K-wire and screw fixation, as well as non-operative treatment are shown in Figures 7e10.
Principles of treatment Recommendations for the acute treatment of physeal fractures depend on the age, the physis involved, fracture classification, growth remaining, displacement, injury mechanism, and status of the soft tissues. Injuries that occur at more rapidly growing physes have a more rapid and better prognosis for remodelling. Younger patients have greater potential for correction of malreduction, yet a growth arrest that occurs in a younger patient typically results in a more severe length or angular deformity. Deformities that are in the plane of joint motion are more easily compensated for. Given the diversity of physeal fractures and the patients that they occur in, it is difficult to give specific recommendations that can be applied universally to all physeal fractures. There is a paucity of quality data to advise on acceptable tolerances in physeal injuries and future research should address this question. Notwithstanding this caveat, acceptable displacements for each physis as described by Nelson and Wongworowat are presented and offer a practical guide (Table 2). For fractures with unacceptable angulation or translation, reduction should be performed. Depending on the fracture pattern, this can be done under conscious sedation or general anaesthesia. Reduction should be performed early if possible. Multiple attempted reductions and reduction performed more than 5 days after the injury are discouraged, as the reduction manoeuvre itself may injure the growth plate. It must be remembered that many physeal injuries may have exceptional remodelling potential, for example the commonly encountered distal radius fracture. The healing of physeal fractures is rapid; many require only 3e4 weeks immobilization.
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Outcomes In the following section we present site-specific observational studies regarding the outcomes of physeal fractures. In some cases, predictors of complications and physeal growth arrest are presented. Although fractures must be considered on an individual basis, we present some typical treatment options. Proximal femur Fracture through the proximal femoral physis is also known as a Delbet I fracture of the proximal femur, or sometimes referred to as a traumatic slipped capital femoral epiphysis (SCFE). Proximal femoral fractures involving the physis are rare and
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Timing of initial ossification and physeal fusion of ossification centres of the long bones (von Lantz et al 1938) Bone
Femur Femoral head Greater trochanter Lesser trochanter Distal epiphysis Tibia Proximal epiphysis Tibial tuberosity Distal epiphysis
Fibula Proximal epiphysis Distal epiphysis Humerus Humeral head Greater tuberosity Lesser tuberosity Capitellum Medial epicondyle Trochlea Lateral epicondyle
Radius Proximal epiphysis Distal epiphysis Ulna Olecranon Distal epiphysis
Appearance of secondary ossification centres e girls
Timing of physeal fusion e girls
Appearance of secondary ossification centres e boys
Timing of physeal fusion e boys
4 months 3 years 11 years 36 weeks (foetal)
16e17 16e17 16e17 17
4 months 3 years 12 years 36 weeks (foetal)
17e18 16e17 16e17 18e19
40 weeks (foetal) 7e15 years 6 months
16e17 19 17e18 *Medial malleolus fuses at 16
40 weeks (foetal) 7e15 years 6 months
18e19 19 17e18 *Medial malleolus fuses at 18
3 years 9 months
16e18 17e18
4 years 1 year
18e20 17e18
Birth-3 months 3 monthse1.5 years 3e5 years 4 months 5 years 8 years 11 years
*Head and tuberosities fuse 4e6 years *Proximally fuse to shaft 18e20 years *Capitellum, lateral epicondyle, and trochlea fuse to shaft at 14 years *Medial epicondyle fuses at 15 years
Birth-3 months 6 monthse2 years 3e5 years 5 months 7 years 9 years 12 years
*Head and tuberosities fuse 4e6 years *Proximally fuse to shaft 19e21 years *Capitellum, lateral epicondyle, and trochlea fuse to shaft at 17 years *Medial epicondyle fuses at 18 years
4 years 1 year
14e15 17
5 years 1 year
15e17 19
8 years 5 years
14e15 17 *Styloid closes at 18e20
10 years 6 years
14e17 19 *Styloid closes at 18e20
Table 1
Delbet I (physeal) fractures had poor outcomes, while patients with other types of proximal femoral fractures had favourable long-term outcomes. Patients with post-traumatic AVN of the hip typically require hip arthrodesis or hip replacement. Proximal femoral physeal fractures should be treated with anatomical reduction, either by closed or open means. Given the intra-capsular nature of this fracture, and the potential for increased intra-capsular pressure secondary to haemarthrosis, some authors recommend capsulotomy to relieve this postulated source of increased pressure about the tenuous femoral head vasculature. Some surgeons will perform an open reduction for this reason, typically by an anterior or anterolateral approach, even if reduction was possible by closed means. Capsular release can also be done in a percutaneous manner. Fracture fixation is typically with one, two or three cannulated screws. In experienced hands, particularly for irreducible fractures, traumatic physeal fractures has to be treated by surgical dislocation, and open reduction.
the literature contains mainly case reports of one or two patients37e39 and mixed case series involving children with both physeal and extra-physeal fractures of the proximal femur.31,40 Proximal femoral physeal fracture can occur with or without dislocation of the hip. When physeal fracture is associated with hip dislocation, the physeal injury can occur either by direct trauma or during reduction of the dislocated hip.37 Approximately 2% of paediatric hip dislocations have separation of the proximal femoral physis. This is a high-energy injury, with a reported AVN rate of 100%, and frequently catastrophic outcomes. Moon et al found that the AVN rate was highest with physeal fractures, AVN rates were 38%, 28%, 18% and 5% for Delbet I (physeal), II (transcervical), III (basicervical), and IV (intertrochanteric) fractures respectively. Older children were more likely to develop AVN, being 1.13 times more likely to develop AVN with each increased year of age. Pape40 reported on 32 patients with mean follow-up of 11.1 years. All patients with
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Generally tolerances for physeal fracture displacement and angulation (Nelson and Wongworawat Orthopedic Tolerances 2009) Region
Degree of angulation/displacement
Distal femur (SH1 or SH2)
5e10 varus/valgus 10e20 flexion/extension Anatomic reduction If >2 years growth remaining 15 plantar tilt 10 valgus for laterally displaced fractures 0 varus for medially displaced fractures if <2 years growth remaining <5 angulation in any plane <1 mm displacement or <2mm gap <2 mm displacement <2 mm displacement 70 angulation, 100% displacement if <5 years 40e70 angulation if 5e12 years 40 angulation and 50% displacement if >12 <2 mm <2 mm No numeric recommendations, but CRPP recommended if unstable or significantly displaced <1mm <45 angulation <¼50% displacement >¼50e60 clinical pronation/supination <2 mm intra-articular gap/step <5 mm 30 angulation if < than 10 years old 15 angulation if >10 years old
Intra-articular fractures (SH3 or SH4) Distal Tibia (SH1 or SH2)
Distal Tibia (SH3 or SH4) Distal Tibia (Triplane SH2, posterior metaphyseal spike) Distal Tibia (Triplane SH4 anterolateral epiphyseal fragment) Proximal humerus
Distal humerus (Lateral condyle, SH2 or SH4) Distal humerus (Medial condyle, SH2 or SH4) Distal humerus (Transphyseal)
Distal humerus (T-condylar, SH3 or SH4) Proximal radius (Radial neck, SH1 and SH2)
Proximal radius (Involving radial head) SH3 and SH4 Proximal ulna (olecranon) Distal radius
Table 2
Distal femur In a series of 42 distal femoral physeal fractures, 40.5% had premature growth arrest and a similar proportion developed varus or valgus angulation.41 In this series type V crush injuries, open injuries, fractures caused by high velocity motor vehicle accidents with severe displacement or multiple associated fractures, and incompletely reduced epiphyseal injuries were associated with poor outcomes. Arkadar et al42 used a retrospective case series of 73 physeal fractures to build a prediction model for growth arrest in the distal femoral physis. In their treatment of these fractures, they had a complication rate of 40% with growth arrest being the most frequent event. Higher complications were associated with fractures that were initially displaced, in those that required reduction, in those treated surgically, in those in which hardware violated the growth plate, and in those with a higher SaltereHarris classification. This study indicates factors associated with distal femoral physeal growth arrest and may well indicate predictors for physeal growth arrest in general. Distal femoral physeal fractures are typically high-energy injuries with a high risk of physeal arrest. For this reason, anatomic reduction is desirable. These fractures could potentially
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be treated in a cast, but are frequently unstable. If it is a type II or IV fracture with a Thurston-Holland fragment, screw fixation can sometimes be placed from this segment into the metaphysis. Type III fractures may be treated with screws or K-wires within the epiphyseal segment only. Type I fractures and some type II and III fractures may require fixation across the physis. In this case, smooth wires crossing as centrally as possible are ideal, with additional fixation provided by a cast or splint. Plate fixation is possible, but care must be taken to avoid injury to the physis and the perichondrial ring. Proximal tibia The proximal tibia consists of both a standard physis and a traction physis or apophysis at the tibial tubercle. Proximal tibial physeal fractures are rare, accounting for 0.5e3% of physeal injuries.43 The injury is typically seen in adolescents and is a high-energy injury, equivalent to knee dislocation in its risk of associated neurovascular injuries. Most commonly the metaphysis displaces posteriorly on the epiphysis, although relative anterior displacement of the metaphyseal fragment (flexion type physeal separation) has been described.43 The posterior physis
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Figure 7 Displaces SH-2 fracture of the proximal humerus of a 7-year-old boy, treated conservatively, showing extensive remodelling within the first 2 years.
closes first and physeal closure progresses anteriorly. This typically results in a SaltereHarris II fracture with the fracture line passing through the physis anteriorly, exiting posteriorly through the metaphysis. In addition to the potential neurovascular complications associated with this fracture, interposition of soft tissues has been described. The pes anserinus is one structure that has been documented as interposed in the physis, preventing reduction.44 The medial collateral ligament has also been described as an interposed tissue preventing reduction.45 The proximal tibia is a frequent site of growth arrest, with one series reporting this complication in 50% of cases.5 Proximal tibia physeal fractures are often high-energy injuries. It is possible to treat them by closed reduction and casting, but they are likely to be unstable. Given the high-energy, this injury may be more susceptible to compartment syndrome. As with other type III and IV fractures, anatomical reduction
should be attempted, and fixation can be by crossed smooth Kwires, or by parallel screws if a Thurston-Holland or epiphyseal fragment is large enough. Distal tibia Rohmiller et al reported a growth arrest incidence of 39.6% in their series of SaltereHarris I and II distal tibial physeal fractures.46 The injury mechanism and residual displacement following reduction were associated with growth arrest. Operative treatment was felt to decrease growth disturbance in some cases. Cass et al reported on a 32 patient series of type IV distal tibial physeal fractures and found that 50% of those involving the medial malleolus resulted in growth arrest, whilst triplane type fractures healed without incident.47 In a retrospective review of 124 distal tibia fractures, 12.1% had premature physeal closure.48 Type II fractures accounted for 67% of the growth
Figure 8 Tillaux fracture (S-H 3) in a 13-year-old girl, fixed with a single screw.
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Figure 9 SH-2 fracture of distal tibia in an 8-year-old boy. A screw was used to gain stability through the Thurston-Holland fragment, with supplemental fixation provided by 2 k-wires.
arrest cases, while Type III and IV accounted for 13% each, and triplane fractures accounted for 7%. Initial displacement and the injury mechanism were predictive factors associated with growth arrest. There was a trend for residual displacement and the number of attempted fracture reductions to relate to growth arrest but these were not statistically significant. Barmada et al49 found that 27.2% of distal tibia fractures were complicated by premature physeal closure. SaltereHarris III and IV fractures involving the medial malleolus accounted for the largest proportion of growth arrests. The number of attempted reductions, initial displacement and treatment did not affect growth arrest. However, a residual physeal gap of >3 mm following reduction was associated with growth arrest. When surgically explored, intervening periosteum was found within the gap,
preventing reduction. The authors recommended open reduction for cases in which residual gap is identified. Distal tibial SaltereHarris type I fractures can typically be treated by closed reduction and casting. SaltereHarris II fractures can be treated in a similar manner, or if unstable could be treated with screw fixation from the Thurston-Holland fragment directed into the metaphysis. Type III and IV fractures are intra-articular and require anatomical reduction, typically by open means with internal fixation. The distal tibial physis closes first postermedially, then progressing centrally and finally it closes anterolaterally. This physeal location is at risk of a unique fracture pattern during the 18 months leading up to physeal closure, when the physis is partially closed. The fracture line typically occurs in three planes d frontal, sagittal and transversedleading to the
Figure 10 A 13-year-old female with S-H 4 ankle fracture. With the physis nearing closure, two partially threaded screws were used in this region.
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name “triplane”. Fractures can be either type IV fractures, or combinations of type II and III fractures. These fractures are frequently fixed with cannulated screws placed parallel to the physis, either in the epiphyseal or metaphyseal segments. As this fracture typically occurs near skeletal maturity, length or angular deformities are uncommon. Due to the proximity to skeletal maturity, some surgeons may elect to place fixation across the physis, but this is situation dependent. A type III fracture can occur in isolation, with avulsion of the anterolateral portion of the distal tibial epiphysis on the anterior tibiofibular ligament. This fragment similarly requires anatomical reduction, and if required can be fixed with screw fixation parallel to the physis. Bioabsorbable pegs have also been used with success in this context.
been treated by early open reduction and internal fixation. The authors recommended immediate anatomic reduction, with or without internal fixation. Another case series documented the use of a Herbert screw52 for a SaltereHarris III fracture. Proximal radius fractures may be treated by closed reduction and immobilization. However, if the fracture is unstable, if there is more than 30 of residual deformity or if there is an unacceptable intra-articular step or gap, then open reduction and internal fixation are reasonable. Internal fixation may be by crossed K-wires, retrograde intramedullary nail, or in rare situations, mini-fragment screw fixation. Proximal ulna The proximal ulna physis is actually a traction or apophyseal physis. Injury in this location is rare, with most injuries of this type occurring in children with osteogenesis imperfect (OI). In a series of five children with OI and olecranon apophyseal fractures, all were treated with open reduction internal fixation. At mean follow-up of 30 months, all fractures had healed, and there were no growth disturbances identified.53 Gwynne-Jones54 reported on apophyseal fractures in 3 boys with osteogenesis imperfect and 4 unaffected boys. All children achieved good function and range of motion with tension band wire fixation, although the children with OI frequently had refractures following hardware removal, and fractured the contralateral apophysis within 1e12 months. Typically proximal ulna fractures can be treated with K-wires and 18-gauge wire tension band constructs. In some situations, as with severe comminution in an older child, plate fixation could be considered.
Proximal humerus Given that the majority of growth occurs from the proximal physis, a large degree of displacement may be accepted at this location. For type III and IV fractures, anatomic reduction should be attempted, and usually smooth crossed K-wires offer sufficient fixation. Distal humerus Physeal fracture patterns of the distal humerus can be difficult to diagnose accurately due to the complex arrangement of multiple secondary ossification centres. These ossification centres appear in a typical order, starting with the capitellum, followed by the medial epicondyle, the trochlea, and finally the lateral epicondyle. In a study of 101 distal humerus fractures in children younger than three at presentation, seven distal humerus physeal separations were identified retrospectively.50 None of these physeal separations had been correctly diagnosed at the initial emergency room assessment. Despite a delayed diagnosis and treatment, all distal humeral physeal separations were felt to have an acceptable outcome. Physeal separations are typically seen in children under the age of 3 years of age, and are typically treated with K-wire fixation. Frequently an arthrogram is used intraoperatively to confirm joint alignment and reduction. Lateral condyle fractures are typically type II or III fractures. If anatomically reduced, the fracture can be treated with immobilization and weekly review. If more than 2 mm of displacement, these fractures are typically treated with open reduction and K-wire fixation.
Distal radius and ulna Cannata et al reported on their series of 157 distal radius and ulna fractures, and at long-term follow-up reported that shortening of 1e6.5 cm occurred in 4.4% of distal radial physeal fractures and in 50% of distal ulna physeal fractures.55 Patients with a length discrepancy of less than 1 cm were asymptomatic, as were patients with ulnar styloid non-union. Of the patients with greater than 1 cm of length discrepancy, only 20% had severe functional deficits. The authors assessed risk factors for growth arrest and concluded that younger age, injuries to the distal ulna physis (regardless of fracture pattern), polytrauma and open injuries were related to greater deformity. Nietoszaara et al56 reported on their series of 109 distal radius physeal fractures and found that both marked initial displacement and non-anatomical reduction were independent risk factors for complications and malunion. The authors reported that 50% of fractures healed in a malunited position despite 85% having an initial anatomical reduction. Pin fixation was recommended to assist with reduction and maintenance of reduction in older patients with significant displacement or non-anatomical reductions. Distal radial and distal ulnar fractures can frequently be treated by closed reduction and casting. If the fracture is unstable, typically K-wire fixation is sufficient to obtain stability, with additional immobility provided by a cast or splint.
Proximal radius Physeal fractures of the radial head are uncommon; the literature contains only a few case reports and case series involving this injury.51 Leung and Peterson reported on a series of 116 children with proximal radius fractures. In the 83 patients with open physes, approximately half had radial neck fractures not involving the physis, the other half having radial head fractures involving the physis. Intra-articular fractures of the radial head are more common once the physis has closed and only six intraarticular fractures were identified in the patients with fractures involving the physis. The authors reported on these six cases and a seventh case that was not part of the initial series. They reported premature closure of the physis in all cases, radial shortening in two cases, but no occurrence of AVN or synostosis. They reported poor outcomes, with the majority of the patients with intra-articular physeal fractures requiring radial head excision or cheilectomy. The only patient with an excellent result had
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Long-term follow-up The management of growth arrest and post-traumatic deformity is beyond the scope of this article and will be the subject of
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10 Roche AF. The sites of elongation of human metacarpals and metatarsals. Acta Anat (Basel) 1965; 61: 193e202. 11 Haines RW. The histology of epiphyseal union in mammals. J Anat 1975; 120(Pt 1): 1e25. 12 Bronner F, Farach-Carson MC, Roach HI, eds. Bone and development. 1st edn. Springer, 2010. 13 Cohen B, Chorney GS, Phillips DP, et al. The microstructural tensile properties and biochemical composition of the bovine distal femoral growth plate. J Orthop Res 1992; 10: 263e75. 14 Dale GG, Harris WR. Prognosis of epiphyseal separation: an experimental study. J Bone Joint Surg Br 1958; 40-B: 116e22. 15 Sauvegrain J, Nahum H, Bronstein H. Study of bone maturation of the elbow. Ann Radiol 1962; 5: 542e50. 16 Morrissy RT, Weinstein SL, eds. Lovell and Winter’s pediatric orthopedics. 6th edn. LWW, 2005. 17 Paley D, Bhave A, Herzenberg JE, Bowen JR. Multiplier method for predicting limb-length discrepancy. J Bone Joint Surg Am 2000; 82-A: 1432e46. 18 Poland J. Traumatic separation of the epiphyses. Smith, Elder, 1898. 19 Salter RB, Harris WR. Injuries involving the epiphyseal plate. J Bone Joint Surg Am 1963; 45: 587e622. 20 Brown JH, DeLuca SA. Growth plate injuries: SaltereHarris classification. Am Fam Physician 1992; 46: 1180e4. 21 Chadwick CJ, Bentley G. The classification and prognosis of epiphyseal injuries. Injury 1987; 18: 157e68. 22 Lombardo SJ, Harvey Jr JP. Fractures of the distal femoral epiphyses. Factors influencing prognosis: a review of thirty-four cases. J Bone Joint Surg Am 1977; 59: 742e51. 23 Peterson HA. Physeal fractures: part 2. Two previously unclassified types. J Pediatr Orthop 1994; 14: 431e8. 24 Peterson HA. Physeal fractures: part 3. Classification. J Pediatr Orthop 1994; 14: 439e48. 25 Ogden JA. Injury to the growth mechanisms of the immature skeleton. Skeletal Radiol 1981; 6: 237e53. 26 Ilharreborde B, Raquillet C, Morel E, et al. Long-term prognosis of SaltereHarris type 2 injuries of the distal femoral physis. J Pediatr Orthop B 2006; 15: 433e8. 27 Wolff J. Das Gesetz der Transformation der Knochen. Berlin: August Hirschwald, 1892. 28 Hueter C. Anatomische Studien an den Extramitatengelenken Neugeborener und Erwachsener. Virchows Arch 1862; 25: 575. 29 Volkmann R. Chirurgische Erfahrungen uber Knochenverbiegungen und Knochenwachsthum. Arch Pathol Anat 1962; 24: 512. 30 Green NE, Swiontkowski MF, eds. Skeletal trauma in children. 4th edn. Saunders, 2009. 31 Moon ES, Mehlman CT. Risk factors for avascular necrosis after femoral neck fractures in children: 25 Cincinnati cases and meta-analysis of 360 cases. J Orthop Trauma 2006; 20: 323e9. 32 Edholm P, Lindblom K, Maurseth K. Angulations in fractures of the femoral neck with and without subsequent necrosis of the head. Acta Radiol Diagn (Stockh) 1967; 6: 329e36. 33 Protzman RR, Burkhalter WE. Femoral-neck fractures in young adults. J Bone Joint Surg Am 1976; 58: 689e95. 34 Ruedi TP, Murphy WM. AO principles of fracture management. George Thieme Verlag, 2001. 35 Skaggs DL, Friend L, Alman B, et al. The effect of surgical delay on acute infection following 554 open fractures in children. J Bone Joint Surg Am 2005; 87: 8e12.
a future review. The long-term follow-up plan however should be determined as part of management of the acute physeal injury. Physeal growth arrest can result in angular deformities and limb length discrepancies with the eventual development of osteoarthritis, gait disturbance, and spinal disorders.57 Limb length discrepancies can be more easily treated by early detection and intervention,58,59 as the window in which growth velocity can be manipulated is limited. If detected later when there is little, or no growth remaining for manipulation or guided growth, often more invasive surgery is necessary, such as osteotomies or distraction osteogenesis for angular correction and limb length equalization. Growth arrests often do not become evident until a number of months have passed. Not all physeal injuries require prolonged out patient follow-up after the acute injury has been treated. Significant physeal fractures should be followed until at least 6 months post-injury, in order to assess for potential growth arrest. At the clinician’s discretion, minor injuries may be discharged after completion of acute management. For example, young patients with low energy type I and II distal radius injuries with minimal displacement, acceptable radiographic and clinical healing may be given instructions to return as required.
Conclusion The majority of physeal fractures heal without incident. When growth arrest occurs it can have devastating effects on function, comfort, cosmesis and quality of life. A comprehensive understanding of growth plate anatomy and function can help the clinician assess to treat these fractures appropriately. By following these simple guidelines, patient outcomes can be optimized. A
REFERENCES 1 Landin LA. Fracture patterns in children. Analysis of 8,682 fractures with special reference to incidence, etiology and secular changes in a Swedish urban population 1950e1979. Acta Orthop Scand Suppl 1983; 202: 1e109. 2 Cooper C, Dennison EM, Leufkens HG, Bishop N, van Staa TP. Epidemiology of childhood fractures in Britain: a study using the general practice research database. J Bone Miner Res 2004; 19: 1976e81. 3 Lyons RA, Delahunty AM, Kraus D, et al. Children’s fractures: a population based study. Inj Prev 1999; 5: 129e32. 4 Peterson HA, Madhok R, Benson JT, Ilstrup DM, Melton 3rd LJ. Physeal fractures: part 1. Epidemiology in Olmsted County, Minnesota, 1979e1988. J Pediatr Orthop 1994; 14: 423e30. 5 Mizuta T, Benson WM, Foster BK, Paterson DC, Morris LL. Statistical analysis of the incidence of physeal injuries. J Pediatr Orthop 1987; 7: 518e23. 6 Kawamoto K, Kim WC, Tsuchida Y, et al. Incidence of physeal injuries in Japanese children. J Pediatr Orthop B 2006; 15: 126e30. 7 Mann DC, Rajmaira S. Distribution of physeal and nonphyseal fractures in 2,650 long-bone fractures in children aged 0e16 years. J Pediatr Orthop 1990; 10: 713e6. 8 Peterson HA, ed. Epiphyseal growth plate fractures. Heidelberg: Springer-Verlag, 2007. 9 Byers PD, Brown RA. Cell columns in articular cartilage physes questioned: a review. Osteoarthritis Cartilage 2006; 14: 3e12.
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48 Leary JT, Handling M, Talerico M, Yong L, Bowe JA. Physeal fractures of the distal tibia: predictive factors of premature physeal closure and growth arrest. J Pediatr Orthop 2009; 29: 356e61. 49 Barmada A, Gaynor T, Mubarak SJ. Premature physeal closure following distal tibia physeal fractures: a new radiographic predictor. J Pediatr Orthop 2003; 23: 733e9. 50 Gilbert SR, Conklin MJ. Presentation of distal humerus physeal separation. Pediatr Emerg Care 2007; 23: 816e9. 51 Leung AG, Peterson HA. Fractures of the proximal radial head and neck in children with emphasis on those that involve the articular cartilage. J Pediatr Orthop 2000; 20: 7e14. 52 Maheshwer CB, Pryor GA. Herbert screw fixation of a Salter Harris type III epiphyseal injury of the radial head. Injury 1994; 25: 475e6. 53 Stott NS, Zionts LE. Displaced fractures of the apophysis of the olecranon in children who have osteogenesis imperfecta. J Bone Joint Surg Am 1993; 75: 1026e33. 54 Gwynne-Jones DP. Displaced olecranon apophyseal fractures in children with osteogenesis imperfecta. J Pediatr Orthop 2005; 25: 154e7. 55 Cannata G, De Maio F, Mancini F, Ippolito E. Physeal fractures of the distal radius and ulna: long-term prognosis. J Orthop Trauma 2003; 17: 79e80. 172e9; discussion. 56 Nietosvaara Y, Hasler C, Helenius I, Cundy P. Marked initial displacement predicts complications in physeal fractures of the distal radius: an analysis of fracture characteristics, primary treatment and complications in 109 patients. Acta Orthop 2005; 76: 873e7. 57 Nakase T, Yasui N, Kawabata H, et al. Correction of deformity and shortening due to post traumatic epiphyseal arrest by distraction osteogenesis. Arch Orthop Trauma Surg 2007; 127: 659e63. 58 Lalonde KA, Letts M. Traumatic growth arrest of the distal tibia: a clinical and radiographic review. Can J Surg 2005; 48: 143e7. 59 Yoshida T, Kim WC, Tsuchida Y, Hirashima T, Oka Y, Kubo T. Experience of bone bridge resection and bone wax packing for partial growth arrest of distal tibia. J Orthop Trauma 2008; 22: 142e7.
36 Wenger DR, Pring ME, Rang M, eds. Rang’s children’s fractures. 3rd edn. Philadelphia: LWW, 2005. 37 Schoenecker JG, Kim YJ, Ganz R. Treatment of traumatic separation of the proximal femoral epiphysis without development of osteonecrosis: a report of two cases. J Bone Joint Surg Am 2010; 92: 973e7. 38 Fiddian NJ, Grace DL. Traumatic dislocation of the hip in adolescence with separation of the capital epiphysis. Two case reports. J Bone Joint Surg Br 1983; 65: 148e9. 39 Aminudin CA, Suhail A, Shukur MH, Yeap JK. Transphyseal fractureseparation of the femoral capital epiphysis: a true SCFE of traumatic origin. Med J Malaysia 2006; 61(suppl A): 94e6. 40 Pape HC, Krettek C, Friedrich A, Pohlemann T, Simon R, Tscherne H. Long-term outcome in children with fractures of the proximal femur after high-energy trauma. J Trauma 1999; 46: 58e64. 41 Czitrom AA, Salter RB, Willis RB. Fractures involving the distal epiphyseal plate of the femur. Int Orthop 1981; 4: 269e77. 42 Arkader A, Warner Jr WC, Horn BD, Shaw RN, Wells L. Predicting the outcome of physeal fractures of the distal femur. J Pediatr Orthop 2007; 27: 703e8. 43 Mudgal CS, Popovitz LE, Kasser JR. Flexon-type SaltereHarris I injury of the proximal tibial epiphysis. J Orthop Trauma 2000; 14: 302e5. 44 Wood KB, Bradley JP, Ward WT. Pes anserinus interposition in a proximal tibial physeal fracture. A case report. Clin Orthop Relat Res 1991; 264: 239e42. 45 McAnally JL, Eberhardt SC, Mlady GW, Fitzpatrick J, Bosch P. Medial collateral ligament tear entrapped within a proximal tibial physeal separation: imaging findings and operative reduction. Skeletal Radiol 2008; 37: 943e6. 46 Rohmiller MT, Gaynor TP, Pawelek J, Mubarak SJ. SaltereHarris I and II fractures of the distal tibia: does mechanism of injury relate to premature physeal closure? J Pediatr Orthop 2006; 26: 322e8. 47 Cass JR, Peterson HA. SaltereHarris Type-IV injuries of the distal tibial epiphyseal growth plate, with emphasis on those involving the medial malleolus. J Bone Joint Surg Am 1983; 65: 1059e70.
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CME SECTION
CME questions based on the Mini-Symposium on “The Hand” The following series of questions are based on the Mini-Symposium on “The Hand”. Please read the articles in the Mini-Symposium carefully and then complete the self-assessment questionnaire by filling in the square corresponding to your response to each multiple-choice question. After completing the questionnaire, either post or fax the answer page to the Orthopaedics and Trauma Editorial Office at the address at the bottom of the RESPONSE sheet. Please photocopy this page if you wish to keep your copy of Orthopaedics and Trauma. Replies received before the next issue of the journal is published will be marked and those reaching an adequate standard will qualify for three external CME points. You will be notified of your marks and a CME certificate will be despatched, via email, for your records.
D The functional impact of diminished rotation is greater than the impact of lost flexion/extension E Volar plates attached distal to the watershed line risk flexor tendon attrition and rupture 5 Which of the following distal radius fracture patterns would most appropriately be treated operatively through a dorsal approach? A A dorsally angulated fracture of the distal radius with concomitant fracture of the ulnar styloid B A fracture extending to the dorsal rim with impaction leaving a defect on elevation C A fracture with a displaced fragment at the dorsal intersection of the sigmoid notch and lunate fossa D A multifragmentary fracture with two or more displaced fracture lines involving the radiocarpal joint E An extra articular fracture with significant dorsal comminution
Questions
6 Which of the following is most frequently associated with intra articular fractures of the distal radius? A Lunotriquetral ligament tear B Radioscaphocapitate ligament tear C Scaphoid fracture D Scapholunate ligament tear E Triangular fibrocartilaginous complex tear
1 What is the effect of increasing ulnar variance by D2.5 mm on the proportion of load on the wrist which is borne by the ulnocarpal joint? A Decreases to zero B Decreases by 20% C No effect D Increases by 20% E Increases by 100%
7 What is the approximate incidence of growth arrest after displaced injuries of the distal ulna epiphyseal plate? A 2% B 5% C 10% D 50% E 75%
2 Which of the following is not a component of the triangular fibrocartilage complex? A Dorsal radioulnar ligament B Lunotriquetral ligament origin C Meniscus homologue D Palmar ulnocarpal ligament E Ulnar collateral ligament
8 Which wrist arthroscopy portal gives the best view of the concavity between the capitate and scaphoid? A 3e4 B 4e5 C 6R D Radial midcarpal E Volar radial
3 Which of the following has no stabilizing role in the wrist? A Dorsal intercarpal ligament B Dorsal ulnotriquetral ligament C Ligament of Testut D Lunotriquetral interosseous ligament E Radioscaphocapitate ligament
9 At wrist arthroscopy after trauma incongruence is seen on both the radiocarpal and midcarpal views of the scapholunate joint, whilst a probe cannot be inserted between the two bones. How would this be classified according to Geissler? A Grade 0 B Grade I C Grade II D Grade III E Grade IV
4 Which of the following statements concerning the management of distal radial fractures is least correct? A Articular steps of 2 mm lead to osteoarthritic change B Dorsal plating carries a significant risk of tenosynovitis and attrition rupture of the extensor tendons C Involvement of the DRUJ impairs forearm rotation
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CME SECTION
Responses
10 Which carpal bone has the greatest surface area:volume ratio? A Capitate B Hamate C Lunate D Scaphoid E Triquetrum
Please shade in the square for the correct answer. B C D E 1 A
11 Which of the following does not contraindicate distal radioulnar joint ligament reconstruction? A Distal radioulnar joint arthritis B Malunion of the distal radius C Sigmoid notch incongruity D Triangular fibrocartilage complex perforation E Ulnocarpal impaction 12 After a fall onto the pronated, outstretched hand a patient is investigated for continuing pain after healing of a distal radius fracture and is found to have an avulsion of the TFCC, including the volar radioulnar ligament, from the radius. How is this classified according to Palmer? A Type 1A B Type 1B C Type 1C D Type 1D E Type 2
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Your details (Print clearly) NAME....................... ADDRESS....................... ............................ EMAIL......................... RETURN THE COMPLETED RESPONSE FORM by fax to þ44-113-392-3290, or by post to CME, Orthopaedics and Trauma, Academic Department of Orthopaedic Surgery, “A” Floor Clarendon Wing, Leeds General Infirmary, Great George Street, Leeds LS1 3EX, UK.
Please fill in your answers to the CME questionnaire above in the response section provided to the right. A return address and fax number is given below the response section.
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CME SECTION
Answers to CME questions based on the Mini-Symposium on “Asia Pacific” Please find below the answers to the Orthopaedics and Trauma CME questions from Vol. 25, issue 3 which were based on the Mini-Symposium on “Asia Pacific”
Answers 1 2 3 4 5 6 7 8 9 10 11 12
A A A A A A A A A A A A
B B B B B B B B B B B B
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BOOK REVIEWS
This book is the result of a collaboration between the American Academy of Orthopaedic Surgeons and the American Knee Society and aims to cover all aspects of knee reconstruction in adults. The authors have produced a text that covers a comprehensive range of current topics relating to knee reconstruction. Approximately half of the book is devoted to arthroplasty-related topics and about half to soft tissue knee surgery. There are arthroplasty sections discussing primary and complex primary knee replacement, complications following arthroplasty and revision arthroplasty. There is also a section on alternative reconstruction procedures. In the soft tissue sections there is coverage of ACL reconstruction, PCL reconstruction, collateral ligament reconstruction, knee dislocation, meniscal injuries and patellofemoral injuries. This text is not designed to be a standard reference textbook, but rather a surgical guide, which will assist surgeons both with the planning and execution of a particular surgical procedure. Each of the 94 chapters contains numerous surgical photographs, diagrams, illustrations and radiographs. The topics are all clearly presented in a logical and well-organized way, which makes finding the information the reader is looking for very straightforward. Each chapter takes a single topic and covers the indications, contraindications, pitfalls and tips. The authors describe the techniques available, as well as giving a step-by-step guide as to how these can be executed, with clear illustrations. A DVD containing 14 surgical videos accompanies the book. The breadth of topics covered in this book is impressive. Within each of the broad sections coverage is given to a comprehensive range of topics going from the most basic through to current controversies and advanced techniques. For example, within the primary knee arthroplasty section the book starts with chapters describing how to do the medial parapatellar approach and then the lateral approach. Chapters then progress through other approaches, biomechanics and bearing surfaces, component design, cemented versus uncemented TKA, patellar resurfacing, pain management, unicondylar arthroplasty and patient factors. This general scheme is carried through each of the sections with wide coverage of both basic and specialized topics. The list of contributing authors is extensive and includes many eminent surgeons within the field of knee surgery. They are almost all from the United States, so inevitably this book does present a very American perspective with much of the evidence quoted coming from the American literature. As an overall package this book is unique. It is superbly written and presented and provides a very clear overall view of the surgical techniques of all aspects of knee reconstruction. In my view it is a book that should have a place in the library of any surgeon with an interest in knee surgery or any orthopaedic trainee aiming towards this. A
Operative techniques in hand, wrist and forearm surgery Thomas R Hunt III, Published by: Lippincott Williams and Wilkins 2010. 944 pages, Price: £185, ISBN: 9781451102550
This new book has been targeted at senior orthopaedic or plastic surgical trainees. It contains approximately 120 chapters which are divided into different pathological entities and anatomical regions. A large number of distinguished authors have contributed and the aim of the book is to provide a step-by-step operative guide supported by relevant basic sciences and anatomy. The book covers both elective and traumatic conditions of bone and soft tissues in the hand and wrist. The chapters follow a common structure, defining and classifying conditions, exploring the appropriate anatomy, the presenting complaints and physical findings, investigations, differential diagnoses and management, both non-operative and surgical. Where things differ from standard texts is that the surgical treatment is then discussed and illustrated, often with intra-operative photographs. It provides step-by-step instructions on how to perform the operations with clear post-operative instructions. The outcomes and complications are also covered providing the reader with the important information required to practically manage these conditions, similar to a recipe cookbook. Each chapter also contains a pearls and pitfalls section providing commonsense advice. The chapters cover the majority of conditions and injuries to the bones and soft tissues of the hand, wrist and forearm. Also included are arthroscopy, arthritis, joint replacement, wrist instability, nerve entrapment, tendon transfers, scaphoid fractures and non-union, fracture fixation, local flaps and some congenital hand surgery. The chapters are mostly well illustrated with clinical intra-operative photographs, although some rely on illustrations. In summary this is an excellent and comprehensive book. It achieves its objective of providing an illustrated textbook providing the reader with relevant information on conditions and practical techniques on how to manage them. The majority of common and some less common conditions affecting the hand and wrist are covered. I would recommend this book to senior trainees or junior consultants who I believe will find it invaluable and I expect it may become one of the standard hand and wrist surgery texts. A
Robert Farnell
FRCS (Eng) FRCS (T&O)
Consultant Hand and Wrist Surgeon,
The General Infirmary at Leeds Great George Street, Leeds LS1 3EX, UK
Advanced reconstruction: knee David Calder
Jay R Lieberman, Daniel J Berry, Frederick M Azar, Publisher: AAOS 2010, ISBN: 9780892034529, Price: AAOS member: $225; Resident: $175, 817 pages
ORTHOPAEDICS AND TRAUMA 25:5
MA MB BChir FRCS FRCS(Orth)
Consultant Trauma and
Orthopaedics, Norfolk and Norwich University Hospital, Orthopaedic Department, UK
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Ó 2011 Published by Elsevier Ltd.
