Common sporting Wrist injuries INTRODUCTION diagnosis
Transcription
Common sporting Wrist injuries INTRODUCTION diagnosis
diagnosis wrist injuries Common Sporting Wrist Injuries In order to properly diagnose the wrist injuries in sport, the clinician should have a good awareness of the basic anatomy of the wrist and investigate appropriately. This article describes common wrist injuries, investigations and treatment. By Dr Mike Rossiter, MB BS MSc (SEM) FFSEM (UK) MRCGP and MR David Warwick, MD FRCS FRCS (Orth) INTRODUCTION Movement Wrist injuries in sport are common but are often poorly diagnosed and therefore not managed adequately. In order to properly diagnose the wrist injury, the clinician should have a good awareness of the basic anatomy of the wrist and investigate appropriately. However, as the wrist is a complicated joint, even with good clinical skills and diagnostic tests an accurate diagnosis is not always possible and therefore a “wrist sprain” may be the most appropriate diagnosis. This article aims to briefly describe the common injuries of the wrist, investigations and treatment. The radio-carpal and ulno-carpal joints in combination allow the wrist to flex, extend, abduct, adduct and circumduct. Rotation (pronation and supination) occurs at the distal radioulnar joint. ANATOMY OF THE WRIST Bones and joints The wrist joint is one of the most complex joints in the body. It is the articulation between the distal radius and ulnar head with the scaphoid, lunate and triquetral bones (the proximal row). It is a synovial ellipsoid joint surrounded by a capsule, which is attached to the lower ends of the radius and ulna and the proximal row of the carpal bones. The capsule is strengthened by a complex system of anterior and posterior ligaments, which stabilise the wrist in all positions. The triangular fibrocartilage complex (TFCC) sits between the ulna head, lunate and triquetrum, stabilising the distal radioulnar joint in rotation and providing a cushion to the ulnar side of the wrist. A synovial membrane lines the capsule and attaches to the margins of the articular surfaces. www.sportEX.net Tendons and muscles The following muscles are responsible for each movement: n Flexion: flexor carpi radialis (FCR), flexor carpi ulnaris (FCU), palmaris longus (PL) (+flexor digitorum superficialis (FDS), flexor digitorum profundus (FDP) and flexor pollicis longus (FPL)) n Extension: extensor carpi radialis (ECR), extensor carpi radialis brevis (ECRB) and extensor carpi ulnaris (ECU) (+extensor digiti (ED), extensor indices (EI), extensor digiti minimi (EDM) and extensor pollicis longus (EPL)) n Radial abduction: FCR, extensor carpi radialis longus (ECRL), abductor pollicis longus (APL) and extensor pollicis brevis (EPB) n Ulnar adduction: FCU and ECU. Intercarpal ligaments The intercarpal joints lie vertically between the individual bones of the proximal row and distal row of the carpus, and horizontally between the proximal carpal row and distal carpal row. The scaphoid and lunate are linked by the scapho-lunate ligament, and the lunate and triquetrum by the luno-triquetral joint. These ligaments are essential for stable function of the wrist. 21 Wrist injuries in sport are often poorly diagnosed and inadequately managed. Even with good clinical skills and diagnostic tests, an accurate diagnosis is not always possible Relationship to the wrist Several tendons, nerves and blood vessels cross the wrist, all of which can be injured or cause pain. The following structures pass anterior to the flexor retinaculum (medial to lateral): n FCU tendon (which attaches to the pisiform bone) n Ulnar nerve n Ulnar artery n Palmaris longus tendon attaching to the flexor retinaculum and palmar aponeurosis n Palmar cutaneous branch of the median nerve n FCR Structures passing beneath the flexor retinaculum (medial to lateral) n FDS and FDP (they share a common synovial sheath) n Median nerve n FPL. The following structures pass posterior to the extensor retinaculum (medial to lateral): n Posterior cutaneous branch of the ulnar nerve n Superficial branch of radial nerve. Structures passing beneath the extensor retinaculum include the fibrous septae from six compartments containing the extensor tendons. Each numbered compartment has a synovial sheath. From radial to ulnar, they are: 1. APL and EPB 2. ECRL and ECRB (posterior to the distal radio-ulnar joint) 3. EPL 4. ED and EI 5. EDM 6. ECU. The radial artery passes between the first and second compartments. INVESTIGATIONS fractures, hook of hamate fracture, displaced scaphoid fractures requiring fixation, declaration or otherwise of a healed scaphoid fracture). CT arthrography enhances accuracy. Ultrasound This is an excellent investigation to assess soft-tissue injuries, tendinopathies and superficial ganglia. It is cheap and can be used in an outpatient setting and can also be used dynamically. However, it is userdependent. X-rays Wrist arthroscopy Plain X-rays can confirm a bone or joint injury. However, a negative X-ray does not exclude a bony injury. A clenched-fist view may demonstrate an acute scapho-lunate ligament rupture, with the gap widening as the joint is axially loaded. Scaphoid views should be taken if there is clinical suspicion of a scaphoid injury, and repeated 2 weeks later if still suspicious (by which time, fracture-line resorption and shift in the fracture’s position usually discloses the injury). Use a carpal tunnel view, with the wrist in dorsiflexion, if a hook of hamate fracture is suspected. This is a very valuable way of investigating the wrist, as most structures can be visualised and passive movements assessed. Magnetic resonance imaging Magnetic resonance imaging (MRI) is the most sensitive method of diagnosing an acute ligament or bone injury and has superseded isotope bone scanning for this purpose. In the non-acute setting when a TFCC or interosseous ligament tear is suspected, the accuracy is enhanced by intra-articular contrast (arthrography). Computed tomography Computed tomography (CT) is the most specific method of identifying bone anatomy (which does not show so well on MRI). CT is best used to define cortical margins that are difficult to define on plain X-ray (eg. comminuted ACUTE WRIST INJURIES These occur mainly from acute trauma, such as being hit by an object or falling on to an outstretched hand. There is also a proportion of athletes who injure their wrists in weight training, where poor technique or the use of weights that are too heavy leads to hyperextension injuries. This may be prevented or reduced by wearing appropriate prophylactic strapping in order to prevent hyperextension. Common injuries n Fracture distal radius n Fracture scaphoid n Wrist “sprain” (a common eventual diagnosis – the exact cause can still be difficult to diagnose even after thorough investigation; it is therefore a diagnosis of exclusion) n Scapho-lunate sprain and other intercarpal ligament sprains n TFCC tear n Scapho-lunate tear n Bone bruising. History A clear history of the mechanism of injury may give a clue to the diagnosis (eg. a fall on an outstretched hand for a fractured scaphoid or forced ulnar deviation and rotation for a TFCC tear). Inspection Look for swelling, bruising and deformity. Palpation Feel systematically to assess each bone, joint and tendon for tenderness. 22 sportEX medicine 2009;41(Jul):21-26 diagnosis wrist injuries Movement Measure the active and passive range of movement in all directions. Do specific stress tests for scapho-lunate instability, luno-triquetral instability and distal radio-ulnar joint instability. Fracture of the distal radius The distal radius is vulnerable in a Figure 1: Radius and ulnar plate Figure 2: Scaphoid non-union fall on the outstretched hand. The type of fracture depends on age. In adolescents, before closure of the growth plates, a physeal injury of the distal radius is more likely to occur than a scaphoid fracture. In young and middle-aged adults, the distal radius fractures across the metaphysis. With increasing energy, the fracture becomes comminuted. Snowboarders and motocross riders are particularly prone to this. In the older, osteopenic patient, the fracture impacts and tilts dorsally (Colles’ fracture). Diagnosis is secured by X-ray. Occasionally CT is needed to define the extent of comminution and plan surgical reconstruction. Simple undisplaced fractures are managed in a cast for 5 weeks. Displaced fractures need manipulation and then stabilisation with metalwork – wires or plates (Fig. 1). Fracture of the scaphoid Figure 3: Scaphoid fixed with a screw and bone graft from the distal radius Figure 4: Terry Thomas sign www.sportEX.net This is a common fracture to miss, and there should be a high clinical suspicion after a fall on to an outstretched hand. Symptoms and signs include a swollen and tender anatomical snuffbox (although the unaffected side may also be tender). There may also be pain applying pressure over the scaphoid tuberosity and scapho-lunate interval. Investigations include scaphoid X-rays. If these are negative and clinical suspicion is still high, further investigation with an MRI scan is indicated. This test is very sensitive for the presence of a fracture because of the dramatic signal changes. However, MRI does not define cortical margins well; if surgery is contemplated, then a CT scan provides much better definition of the fracture line. The main risk of missing this fracture is non-union (Fig. 2) due to its poor blood supply leading to chronic wrist pain and loss of grip strength. Ninety per cent of undisplaced waist fractures heal in a promptly applied cast within 8–12 weeks. The union rate for proximal pole fractures and displaced fractures is much less reliable. These latter two configurations warrant early surgery. There is an increasing trend to fix undisplaced waist fractures immediately with a percutaneous cannulated compression screw in order to speed recovery and return to training (Fig. 3). Scapho-lunate ligament tear The scapho-lunate ligament maintains the proximal pole of the scaphoid adjacent to the lunate (scapho-lunate gap) and stabilises the palmar rotation force of the scaphoid against the dorsal rotation force of the lunate. This structure is injured when the wrist hyperextension mechanism that might result in a scaphoid fracture instead disrupts the adjacent scapholunate ligament. This may occur as a partial tear with pain but no instability, best treated by rest and sometimes arthroscopic debridement. More complete injuries may result in dynamic scapho-lunate instability, with normal plain X-rays but pain with use and an increased radiological scapho-lunate gap with the fist clenched. Complete disruption of the scapho-lunate ligament results in an instability pattern visible on plain X-rays, with widening of the scapho-lunate gap (the “Terry Thomas sign”) (Fig. 4) and the lunate tilted backwards with the scaphoid flexed on the lateral view (dorsal intercalated segment instability, DISI). On examination, there is tenderness over the scapho-lunate ligament (just beyond the bony prominence on the back of the distal radius known as Lister’s tubercle). It may be possible to elicit a positive Watson’s test (not specific for the injury). The test involves applying pressure to the palmar portion of the scaphoid while moving the wrist into ulnar deviation. When the wrist is then moved into radial deviation, the scaphoid cannot flex as it is blocked by the examiner’s thumb. If the scapholunate ligament is torn, the scaphoid will move dorsally against the examiner’s finger, causing pain. When the scaphoid pressure is removed, the scaphoid then moves back into position with a clunk. MRI arthrography is helpful in diagnosing this injury, with characteristic soft-tissue signal changes and contrast flowing through the space. Wrist arthroscopy is the definitive investigation. The tear can be identified and the severity of instability established. In later stages, associated arthritis can be assessed. Minor tears can be debrided. Complete unstable scapho-lunate injuries should be repaired as soon as they are diagnosed. In the first few weeks, a direct repair is possible; thereafter, the tissue degrades and an 23 indirect repair (capsulodesis) is needed. Results of repair are unpredictable and often disappointing if delayed months after the initial injury. If left for too long, then irreversible deformity and osteoarthritis can develop. Over time, the abnormal position of the scaphoid and lunate results in degenerative changes at the radio-scaphoid, midcarpal and then radio-lunate joints and are referred to as scapho-lunate advanced collapse (“SLAC wrist”). Salvage procedures include, among others, proximal row carpectomy, scaphoid excision with mid-carpal fusion, and full wrist fusion. Fracture of hook of hamate The hook of the hamate lies distally and radial to the pisiform and forms the lateral border of the canal of Guyon, through which the ulnar artery and nerve run. Fracture of the hook is classically from either a direct blow or blocked swing of a club or racquet. Most patients have pain and tenderness on the ulnar side of the palm, with pain increased by gripping and reduced grip strength. There may also be ulnar nerve paraesthesia and mild carpal tunnel syndrome signs and symptoms. In delayed cases, the FDP tendon to the little finger, which runs alongside the hook, may rupture. The fracture cannot be diagnosed on simple anteroposterior and lateral X-rays. It can sometimes be seen on a carpal tunnel view. If there is still diagnostic doubt, a CT scan is the definitive test (Fig. 5). If diagnosed in the first 2–3 weeks (unusual), then treatment is by immobilisation in a cast. If the patient presents later, then surgical excision of the hook produces very good results. CHRONIC WRIST PAIN Excluding missed acute injuries, causes include: n Tendinopathies n Ganglion and dorsal impingement n TFCC injuries n Neuropathy n Arthritis n Kienbock’s disease n Piso-triquetral pain n Snapping ECU. General assessment History The affected part of the wrist may 24 indicate the problem (eg. dorsal may be intersection syndrome). Stiffness at rest may indicate a tendinopathy or arthritis, whereas pain on loading (eg. in gymnastics) may be due to a bony or joint problem. Neural symptoms may be due to a local entrapment, but if the symptoms extend above the wrist, then it is important to exclude pathology in the elbow or neck. Figure 5: CT scan of fractured hook of hamate Examination The wrist should be examined systematically: look, feel, move. Investigation Depending on the likely diagnosis, there is a role for X-rays, MRI, ultrasound, nerve conduction studies and arthroscopy. Tendinopathy De Quervain’s tenosynovitis This is an inflammation of the APL and EPL tendon in the synovial sheath and is more common in gripping sports such as rowing and canoeing. There is tenderness and swelling over the radial styloid and a positive Finklestein’s test (closing the fingers over the thumb and then ulnar deviation of the wrist produces pain over the radial styloid). The tenosynovitis can be detected on ultrasound scan. The most effective primary treatment is an injection of cortisone into the tendon sheath (Fig. 6). Splinting or strapping to immobilise the wrist and physiotherapy (ultrasound, massage, stretches) are adjuncts. Surgical decompression of the tendon is usually curative but rarely necessary. Intersection syndrome This is actually a frictional bursitis where the APL and EPL tendons cross over the ECR. There is tenderness and crepitus just proximal and radial to Lister’s tubercle. This is a relatively common condition in rowers, canoeists and racquet sportspeople. The diagnosis, usually made clinically, can be confirmed on either ultrasound or MRI. Treatment consists of physiotherapy, non-steroidal antiinflammatory drugs (NSAIDs), relative rest and correction of any technique errors. If this fails, a cortisone injection into the area is often effective. Other tendinitides These are common in endurance sports with repetitive wrist movement, Figure 6: Injection for de Quervain’s Figure 7: Volar ganglion Figure 8: Ulnocarpal impaction such as rowing and canoeing. Increased risks in these sports include blade design, poor grip and poor technique, possibly from fatigue. Relative rest, physiotherapy and strapping, as well as correcting any causative factors, are usually successful. An accurate cortisone injection is very helpful in more significant cases. Surgery is rarely required. sportEX medicine 2009;41(Jul):21-26 diagnosis wrist injuries Ganglion and dorsal impingement Ganglion cysts Ganglion cysts are idiopathic but probably reflect a variation in normal joint or tendon sheath function. Cysts near joints are connected to the joint. The leading theory is that a type of check valve forms that allows fluid out of the joint but not back in. The cyst contains clear fluid similar to, but thicker than, normal synovial fluid. They are most often found around the scapholunate joint but can occur anywhere around the wrist joint (Fig. 7). Diagnosis may be made clinically, or small ganglion cysts can be identified on ultrasound or MRI. However, the cysts are often incidental and therefore it is important to ensure that this is the cause of the painful wrist rather than masking another cause. Ganglion cysts often come and go spontaneously, and so most of the time they can be left alone. Symptomatic ganglions can be treated by direct pressure (traditionally hitting it with the family Bible!), aspirated or excised, but all of these methods have a risk of recurrence (70–80% with pressure, 40% with aspiration, 10% with excision). Impingement Dorsal synovial impingement is common in sports that involve repetitive hyperextension. It is caused by the capsule and synovium snagging between the distal edge of the radius and the back of the lunate-capitate on extension. The athlete complains of pain on hyperextension under load, pointing to the back of the wrist joint. On examination, there is focal tenderness and the pain is reproduced by forced passive hyperextension. Occasionally, ultrasound or MRI shows a lesion (and excludes the differential diagnosis of a small or occult dorsal wrist ganglion). If suspected clinically, then a cortisone injection is both diagnostic and therapeutic. Immobilisation in a splint is helpful. For refractory cases, or to secure the diagnosis, wrist arthroscopy is recommended. TFCC injuries The TFCC is the stabiliser of the wrist joint and consists of triangular cartilage, ulnar meniscus, ulnar collateral and carpal ligaments, and ECU tendon. It can be injured in two ways. A central perforation occurs with www.sportEX.net a fall on the outstretched hand but more frequently occurs as a natural degenerative process in patients with a relatively long ulna (ulnocarpal impaction; Fig. 8). The patient has pain in the ulnar corner, which is worse on sporting manoeuvres needing ulnar tilt. On examination, there is tenderness over the ulnar head, with pain provoked by forced ulnar tilt. Diagnosis is confirmed by MRI arthrography. A cortisone injection helps mild cases; more severe cases need arthroscopic surgery to trim the tear and decompress the ulnar head. A peripheral detachment occurs with a violent wrench or fall in rotation on the hand. The distal radio-ulnar joint becomes unstable. This is a rare but disabling injury for the athlete. Diagnosis is confirmed by anteroposterior instability on balloting (compressing) the ulnar head. Treatment requires surgery (arthroscopic or open) and prolonged rehabilitation. Neuropathy Carpal tunnel syndrome This condition is caused by compression of the median nerve (Fig. 9) within the carpal tunnel of the wrist, leading to tingling and pain or paraesthesia in the median nerve territory of the hand (thumb, index, middle and radial side of the ring fingers). Symptoms may radiate to the elbow and are often worse at night. It is important to exclude the neck as the source of the pain. The condition is seen in sports that involve repetitive wrist flexion (eg. rowing) and in sports with direct pressure on the nerve (eg. cycling, handball). Diagnosis is usually clinical with a positive Phalen’s test (passive wrist flexion reproducing symptoms) or Tinel’s test (tingling in the median nerve territory of the hand by tapping over the median nerve in the wrist). Thenar muscle wasting and established sensory loss indicate severe compression and justify urgent assessment for surgical release. If there is diagnostic doubt, then nerve conduction tests confirm the cause. In mild cases, treatment consists of relative rest, NSAIDs and night splints, although these are often poorly tolerated. A cortisone injection into the carpal tunnel is effective in around 70% of cases. Surgical decompression is usually curative. Ulnar nerve compression The ulnar nerve can be compressed as it passes through Guyon’s canal. It is often seen in cyclists who use drophandlebars due to direct pressure over the nerve as the wrist is forced into ulnar deviation. Compression causes pain and paraesthesia in the little finger, ulnar side of the ring finger and hypothenar eminence. In severe cases there is reduced grip, with wasting of the hypothenar and interosseous muscles. Diagnosis is often made clinically but, again, nerve conduction tests may be necessary. Mild cases usually resolve with relative rest, NSAIDs and a change of Acute wrist injuries mainly occur from acute trauma, such as being hit by an object or falling onto an outstretched hand. There are also some athletes who injure their wrists in weight training, where poor technique or too heavy weight leads to hyperextension injuries. 25 changes, a gadolinium-enhanced MRI scan is diagnostic. Treatment consists of immobilisation in early cases. The natural history is often benign. Some cases need surgery to decompress or revascularise the lunate. Piso-triquetral pain Figure 10: Keinbock’s disease grip. Severe and persistent cases may need surgical decompression. However, scar tenderness can be an issue. Osteoarthritis Snapping ECU This may follow an acute injury, usually a poorly executed tennis shot, or it may be exposed as a chronically developing condition. In normal rotation, the ECU passes across the back of ? ? Have you had any experience with “problem” wrist injuries? Which investigations helped to provide a diagnosis? w The wrist can develop arthritis spontaneously as part of an individual’s genetic programme. The demands of sport may expose symptoms (although there is no evidence that sport causes arthritis, unless there is a predisposing sporting injury). Previous sporting injury can cause arthritis in specific patterns (eg. scaphoid fracture, scapho-lunate injury, pisiform fracture, intra-articular radius fracture). Initial treatment is conservative – modifying the technique and tempering sporting ambitions. Splinting and an occasional cortisone injection can help. There is no role for physiotherapy. Some patients require surgery for intrusive symptoms; if possible, total wrist fusion is avoided. Some part of the complex articulation can be preserved in order to maintain some movement (partial wrist fusion). However, loss of wrist movement and coordination from surgery is likely to reduce sporting performance considerably. Modern wrist replacements, although increasingly trusted for low-demand individuals, are unlikely to withstand the demands of an athlete. Piso-triquetral arthritis is unusual, but it can follow a fracture or can develop spontaneously. Pain is located on the palmar-ulnar corner of the wrist, aggravated by flexion in ulnar deviation (eg. tennis, golf). A special supinated lateral X-ray is needed to show this joint. Treatment is by cortisone injection or excision. Piso-triquetral instability can occur in patients with lax joints or with a previous injury that has damaged the ligaments that support this joint. Again, there is pain in the ulnar-palmar corner, aggravated by grip in flexion and ulnar deviation. On examination, the joint can be balloted laterally. Treatment is by amending sporting posture or, occasionally for troublesome symptoms, pisiform excision. the ulnar head, restrained in a groove. If the restraints tear or gradually fail, then the ECU snaps across the back of the ulna head in rotation. An acute tear (very rarely diagnosed) is treated in an above-elbow cast. A chronic injury needs surgical reconstruction of the ECU sheath. Clinical Sports Medicine (revised 2nd edn) by Peter Bruckner and Karim Khan was used as a template for this article. online Launch the extra by clicking on the image A series of animations overviewing the anatomy of the wrist The Authors David Warwick, MD BM FRCS FRCS(Orth) European Diploma of Hand Surgery is a consultant hand surgeon at Southampton University Hospitals NHS Trust. He is also Reader in Orthopaedic Surgery at the University of Southampton. His elective and trauma practice is confined to conditions of the hands, wrists, elbows and nerves. He provides a tertiary referral service for the States of Jersey, the Isle of Wight and the British army (training and recruitment). He looks after many sportspeople, including four gold medal Olympians and two silver medal Olympians. He has looked after national-level rugby, diving, hockey, cricket and soccer players. He is club surgeon to Southampton Football Club and Hampshire County Cricket Club. He has admitting rights at Wessex Nuffield Hospital, BUPA Southampton Hospital and Jersey General Hospital. He has written many articles and book chapters; most recently, he edited and authored the Oxford Handbook of Hand Surgery. Keinbock’s disease This is an avascular necrosis of the lunate (Fig. 10). The aetiology is unclear but is possibly from repeated trauma. There is chronic mid-dorsal and volar wrist pain. It is more common in athletes in their twenties. Diagnosis is made by X-ray, which shows sclerosis of the lunate and, in later cases, crumbling of the lunate, with altered alignment of the other carpal bone and arthritis. If suspected before plain X-ray 26 Mike Rossiter, MB BS MSc (SEM) FFSEM (UK) MRCGP is a sports physician at the English Institute of Sport, Bisham Abbey and an associate specialist in orthopaedics and sports and exercise medicine at the North Hampshire Hospital Basingstoke. He also has sports clinics in Basingstoke and Parkside Hospital. He is an honorary senior lecturer and examiner in sports and exercise medicine at the University of Bath. He is club doctor at London Irish Rugby Club and chief medical officer for England and Great Britain Hockey and also for the Great Britain Synchronised Swimming Team. He was team doctor for both the men’s and women’s hockey teams at the Commonwealth Games in 2006 and the Beijing Olympics in 2008. He was one of the club doctors at Southampton Football Club until 2008. sportEX medicine 2009;41(Jul):21-26