Sp orts Mad . 1997 Apr: 23 (4): 261-270

INJURY CLINIC

0112- 1 642/97/0004 ~6 1 /S05.oo10

© Adis Internatio na l Umited. All rights rese rved.

Rock Climbing Injuries Michael D. Rooks Department of Orthopaedic Surgery, Emory University School of Medicine, Atlanta, Georgia, USA

Contents Summary 1. Background Information . 2. Technique, Equipment and Judging. 3. Injuries . . . . . . . . .... . 4. Anatomy and Pathophysiology 5. Diagnosis . . . . . . . . . 6. Treatment and Prevention 7. Conclusions . . .

Summary

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Three-quarters of elite and recreational sport climbers will suffer upper extremity injuries. Approximately 60% of these injuries will involve the hand and wrist, the other 40% will be equally divided between the elbow and the shoulder. Most injuries will be tendonopathies secondary to strains, microtrauma or flexor retinacular irritation. However, up to 30% of these injuries in up to 50% of elite climbers will involve the proximal interphalangeal (PIP) region . These injuries are more serious and consist of varying degrees of flexor digitorum sublimis insertional strains, digital fibro-osseous sheath ruptures and PIP joint collateral ligament strains. Early changes in climbing schedules, stretching and exercise habits, and protective digital taping are necessary to protect and rehabilitate these athletes.

1. Background Information Rock climbing is one of the most rapidly growing sports in the world. Local, national and international competitions are becoming common, and consideration for inclusion in the Olympic Games is underway. With the explosion of artificial walls, almost anyone can participate in this sport with the rental or purchase of a pair of climbing shoes and a harness. As few as 10 years ago, a rock climbing venture would have required the purchase of several hundred dollars worth of specialised and difficult-to-find equipment. Good instruction, by book or guide, was hard to find . Finding an appropriate

rock face would often require a long drive and miles of hiking. Rock climbing is only one of several separate disciplines that fall under the general sport of mountaineering, or alpinism. Mountain climbing evolved as a sport in the late eighteenth and early nineteenth centuries first as a Swiss, and then more fervently as a British, activity. By the end of the nineteenth century, all the major peaks in Europe, the Americas and Africa had been climbed. By the mid 1960s, the major peaks of the Himalayas had also been climbed)'] The disciplines associated with alpinism include high altitude camping and survival techniques, glacier

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travel, ice climbing and rock climbing. Ice climbing is divided into the areas of waterfall ice (climbing frozen waterfalls) and alpine ice (steep snow and glacier fields, involving avalanche safety techniques). Rock climbing is divided into: (i) traditional (free rock climbing), (ii) aid (including bigwall techniques), and (iii) sport climbing. In aid climbing, a featureless, near-vertical to overhung rock wall is climbed by placing aid pieces (small metal hooks, metal pitons, malleable aluminium and copper blocks called mashies, or traditional protection pieces) in thin cracks and on small flakes. Vertical progress is made by directly climbing on these pieces. In free rock climbing, the climber climbs by pulling themselves upward on the physical features of the rock face (cracks, flakes, horns, etc.). Protection pieces are placed every 3m or so to catch the climber in case of a fall. These protection pieces include passive 'pro' (nuts, hexs, etc.) and a variety of active camming devices that actively lock themselves into cracks. Sport climbing includes all climbing done on artificial walls and climbing on natural rock faces where a rope is fixed above the climber to catch any falls, or where the climber climbs with the rope below him but fixing it to machine bolts or similar permanent protection pieces fixed to the face of the rock. The essential distinction between traditional free climbing and sport climbing is that the risk of a 6 to 12m fall on potentially questionable protection is avoided with sport climbing. As a matter of style, traditional free rock climbing can be done without the use of a rope and is referred to as solo free climbing; mistakes here are often fatal. The popularity of rock climbing has evolved in relation to 3 major developments in the sport. Around 1945, the first nylon Kernmantle (a ropemaking technique with parallel twisted core yarns surrounded by a protective sheath) ropes were produced.[2l These ropes were vastly superior in strength and shock absorption to previous ropes, which made falling on a climb survivable. In the 1960s, specialised rock shoes using newly devel© Adis International Limited. All rights reserved.

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oped thermodynamic rubbers made climbing easier and significantly opened up the range of rock faces which could be free climbed.[3] The third development was the arrival of easily available good artificial walls in the mid 1980s. These made climbing accessible to the masses.

2. Technique, Equipment and Judging Because rock climbing is a relative new sport to many physicians, a general overview of the basics of traditional free and sport climbing is in order. The basic equipment needs are a rope, a climbing harness, belay device, rock climbing shoes and a climbing surface. For traditional free climbing, carabiners, nylon runners and a selection of protection pieces, or 'pro', is also necessary.

Fig. 1. Sport climbing typically involves climbing on an artificial wall using a top-rope technique.

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Rock Climbing Injuries

Sport climbing is done by top-rope and lead technique. In top-rope technique, the climber is tied in by their harness to a rope that extends above them and over a fixed point at the top of the climb and back to the ground (see fig. 1). On the ground a 'belayer' passes the free end of the rope through a friction device on their harness and takes up rope as the climber moves upward. If the climber falls the weight is immediately taken by the belayer, preventing any significant fall or injury. In lead technique (common in high level competitions), a more traditional approach is used. Along the climbing route are fixed bolts and hangers. Each hanger has an aluminum clip, a carabiner, attached to it with another carabiner hanging below this one, the 2 held together by a nylon loop. This 'biner' (pronounced 'bean-er') loop 'biner' arrangement is called a quick draw. The climber is tied in to the rope which passes through the belayer's friction device a few feet from the climber. As the climber ascends, the belayer feeds them more rope. The climber clips the rope to the free 'biner' as they approach each quick draw, thus any fall is limited to twice the distance between climber and the last clip. Traditional free climbing is similar to lead sport climbing (see fig. 2), and by definition is done on a natural rock face. As the lead climber climbs, they place protection pieces into natural cracks and slots in the rock. A quick draw is clipped to the ' pro' and then to the rope. More 'pro' and quick draws are added every 6m or so where possible. When the lead climber gets 30 to 50m above the ground, they clip themselves to the wall and belay the climber below to this point. The second climber gathers all 'pro' and quick draws on the way up and the process is repeated until the top of the climb is reached. The rating system for free climbing is fairly complex and very subjective. The German Welzenbach classification rates all climbing into 6 general grades. This goes from grade I which is little more than off-trail hiking through grade 4 (potentially fatal falls), grade 5 (all-roped free © Adis International Limited. All rights reserved.

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Fig. 2. Traditional climbing involves the use of protection pieces. lead technique and natural rock formations. Other outdoor backcountry skills often come into play.

climbing) to grade 6 (direct aid climbing). By the 1950s, roped free climbing (grade 5) had been subdivided into 10 subdivisions (class 5.0 to 5.9) in the Yosemite decimal system, a descendant of the Tahquitz Rock system introduced by the Sierra Club in 1937. In the 1970s and 1980s, this system was enlarged to accommodate improved climbing abilities, largely secondary to improved shoes, by adding the classes of 5.10 to 5.14 with further a to d subdivisions in the lower 4 classes. The 5 is sometimes omitted in describing the difficulty of a climb (l2b as opposed to 5. 12b),f31 Because of the subjective nature of this classification, competition climbs are rated by the highest stable point reached, with face-offs when more than I climber tops off. Sports Med. 1997 Apr: 23 (4)

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Fig. 3. Three-quarters of all sport climbers will develop injuries. 60% of these injuries will involve the hand and wrist. The other 40% is equally divided among the shoulder and elbow.

3. Injuries Mountaineering and rock climbing are perceived by most people as being inherently dangerous activities. Assaults on major mountains like Denali in Alaska or Everest (Chomolungma) in the Himalayas are associated with mortalities of from 2 to 4%[4,5] and accident rates approaching 20%)4] There is little consolation in the fact that 4 times as many people have reached the summit of Everest than have died on it.[5] Most of these deaths are avalanche, altitude and weather related. The incidence of accidents in traditional rock climbing is closer to 2 to 4 per 1000 climber-days (0.2 to 0.4%). Half of these involve fractures (one-quarter of which involve the ankle). 80% of these injuries are due to falls and the rest are equally divided between hypothermia and falling rocks. Only 10% of these injuries are fatal (about I in 10 000 to 20 000 climber-days»)6] Sport climbing pretty much eliminates these risks, However, this elimination of the risks inherent in traditional climbing has produced a whole new set of problems. The sport climber climbs © Adis International Limited. All rights reserved.

without fear of falling because of the security of their ropelbelay system. In fact, they climb until they fall striving for the highest point on a route and gradually working out the necessary moves. Access is no longer a problem when the rock face is 20 feet from the car. You can climb daily and for hours each day. The injury pattern in the sport climber consists of high stress and repetitive stress injuries. Almost all of these injuries are upper extremity problems owing to the emphasis on vertical and overhung climbs on artificial walls. Three-quarters of sport climbers will suffer upper extremity injuries)7,8] Elbow and shoulder involvement is almost equal at roughly 15 to 20%)7,9] The most commonly involved site is the hand and wrist, with 60% of injuries and approximately 50% of climbers affected (see fig. 3).[7,10-13] The single most common site for injury in the sport climber appears to be the proximal interphalangeal (PIP) jointJ7,10-13] PIP joint injuries are present in over 50% of elite sport climbers, accounting for almost 30% of all injuries. The rest of the review is concerned with these injuries.

4. Anatomy and Pathophysiology Over three-quarters of sport climbing injuries are associated with the extrinsic digital flexor system of the hand and forearm (i.e, the flexor digitorum profundus and the flexor digitorum sublimis). Injuries at the extensor carpi brevis origin, the biceps brachialis insertion and the shoulder rotator cuff cover the essence of any other pathology specific to climbing.[7,9 1 The flexor digitorum profundus consists of 4 interconnected muscles that originate at the proximal ulna, These unipennate muscles give rise to their respective tendons in the forearm, cross the wrist through the carpal tunnel, and then travel in the digital fibro-osseous sheaths to their insertions at the volar base of the distal phalanges. In the fibro-osseous sheaths, the profundus passes through a slit in the more superficial sublimis tendons (see fig. 4). Sports Med. 1997 Apr; 23 (4)

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Rock Climbing Injuries

FDS

PIP joint collateral ligament

FOP - ---ff-\--

Fig. 4. The extrinsic flexor tendons of the digits pass through a continuous synovial lined fibro-osseous sheath extending from the mid-palm to the base of the distal phalanx. There are 5 thick fibrous annular thickenings in these sheaths that hold the tendons close to the digital skeleton, known as annular pulleys. The sheaths between these annular thickenings are filmy and thin except for fibrous cruciate thickenings. A2 , A3 , and A. are the fibrous second, third and fourth annular pulleys respectively. Abbreviations: FOS flexor digitorum sublimis tendon; FOP flexor digitorum profundus tendon; PIP proximal interphalangeal.

=

The profundus produces all the flexor strength at the distal interphalangeal joint and a little more than half the strength at the proximal interphalangeal joint. With the occasional exception of the index, the profundi act essentially as a single functional unit. The flexor digitorum sublimis consists of a complex array of 4 muscle systems in which 2 to 3 of the muscles (index, small and frequently the ring) are digastric. The sublimis to the long finger is totally independent while the other 3 generally share proximal interconnections with about a half or their excursion interconnected. The sublimis takes origin from the medial epicondyle of the elbow, the proximal radius and ulna, and the fibrous sublimis arch © Adis International Limited. All rights reserved.

=

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connecting the medial epicondyle and radius. The tendons are formed in the forearm, pass through the carpal tunnel at the wrist superficial to the profundus tendons and through the digital fibroosseous sheaths to a broad insertion on the middle phalanges. Unlike the profundi, the sublimi are not interconnected at the wrist and palm and therefore provide independent finger flexion) 12] The profundi give the brute force of finger flexion while the sublimi provide additional power at the proximal interphalangeal and metacarpal-phalangeal joints as well as independent finger flexion and more finesse of motion. Overuse and high loads on these 2 muscles produce a variety of tendonopathies secondary to Sports Med. 1997 Apr; 23 (4)

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microtrauma, strains and overt tears. Further injuries occur as well through friction with the flexor retinaculums at the carpal canal and in the digital fibro-osseous sheaths. Medial epicondylitis at the sublimis origin, mid-forearm pain at the musculotendinous junctions and flexor tenosynovitis in the wrist, palm and fingers are the results. Chronic oedema in the carpal canal and/or entrapment of the median nerve between tensing flexor tendons and the transverse carpal ligament can produce carpal tunnel syndromes. Because of the hooked and crimped grips common in climbing (see fig. 5), the greatest forces are centred around the PIP joint region, particularly in the long and ring fingers. Excessive and prolonged forces from the sublimis and the profundus tendons on the fibroosseous sheaths can result in acute and chronic rupture of the digital fibro-osseous sheaths at the A3 and A2 annular pulleys. This can result in pain, PIP flexion contractu res and tendon bowstringing across the PIP joint. These same forces associated with the crimped grip can result in the classic 'climber's finger' injury first defined by Duval.l 131 This injury consists of varying stages of rupture of the sublimis insertion on the middle phalanx. This can proceed from a partial tear through complete rupture and secondary A3 and even A2 flexor pulley ruptures (see fig. 6). In addition to these 2 problems, direct PIP joint injuries can occur with volar subluxation of the middle phalanx on the proximal with subsequent collateral ligament strains, and secondary fixed PIP flexion contractures. Any of these 3 injuries can progress to fixed PIP flexion contractures and permanent joint arthroses (see fig. 7).

5. Diagnosis

Fig. 5. The 2 common grips used in sport climbing are the cling or hooked (top), and the crimp (bottom). The crimp grip puts particularly high stresses across the proximal interphalangeal (PIP) joint, the flexor digitorum sublimis insertion, the digital fibro-osseous sheath and the PIP collateral ligaments.

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Sport climbers present with complaints of upper extremity pain, swelling, and occasionally, PIP contractures. They may give a history of a 'pop' or 'snap' associated with annular pulley or sublimis insertional ruptures. Physical examination should firstly be directed towards the hands and fingers. Direct tenderness and swelling over the volar base Sports Med. 1997 Apr; 23 (4)

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FOS Fig. 6. Climbing injuries associated with the crimp grip include: (top) partial to complete tears of the flexor digitorum sublimis (FOS) insertions on the middle phalanx. and (bottom) complete or partial rupture of the second and third annular pulleys (A2 and A3) . complete sublimis avulsion and proximal interphalangeal (PIP) jOint subluxation and collateral ligament sprains. Abbreviation: FOP = flexor digitorum profundus tendon.

of the proximal phalanges and palm are indicative of flexor tenosynovitis. This diagnosis is further confirmed by similar findings in the distal volar forearm and wrist. Loss of active or passive PIP © Adis International Limited. All rights reserve d .

joint extension as well as direct tenderness over the lateral or volar PIP joint is a much more serious finding. These signs should be carefully distinguished from the relatively much less serious Sports Med. 1997 Apr; 23 (4)

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flexor tenosynovitis associated with proximal phalangeal pain and oedema. Pain, swelling and contractures around the PIP joint (see fig. 7) suggest damage to the sublimis insertions, the digital fibro-osseous pulley system or the PIP joint itself. The volar PIP joint region should be palpated with the digit actively contracted in the crimped position to palpate for volar flexor tendon subluxation, or bow-stringing. This indicates flexor pulley system rupture with or without sublimis injury. This may be associated with loss of active PIP extension. Complete sublimis rupture can be ruled out by demonstrating active PIP flexion of the questioned digit with the PIP and DIP joints of the other digits held passively extended (the 'sublimis test'). It should be appreciated that 15% of people cannot actively flex the PIP joint of the small digit without flexing the adjacent ring digit PIP joint simultaneously. In another 15%, the small finger sublimis tendon is congenitally absent. Pain on the sides of the PIP joint and fixed PIP flexion contractures indicate varying degrees of PIP joint injury involving the collateral ligaments. This mayor may not be associated with oedema. PIP joint injuries can occur in isolation or secondary to sublimis or digital pulley system injuries. Palpation should be carried out over the medial and lateral epicondyles of the elbow, looking for medial or lateral epicondylitis. Medial epicondylitis is usually due to microtrauma at the sublimis origins and is often associated with more distal flexor tenosynovitis. Lateral epicondylitis occurs at the extensor carpi radialis brevis origin and is associated with contraction of this muscle for wrist stabilisation during grip. The specific physical test for lateral epicondylitis is the production of lateral epicondylar pain with active extension of the wrist against resistance, Cozen's test. Production of lateral epicondylar pain with elbow extension, pronation and passive wrist flexion (Mill's manoeuvre) is confirmatory. Medial epicondylar pain with active wrist flexion against resistance in supination, a reverse Cozen's test, is specific for medial epicondylitis. A reverse Mill's test, passive wrist extension in supination with the elbow extended, © Adis International Limited. All rights reserved.

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Fig. 7. This climber presented with a fixed proximal interphalangeal jOint contracture and subluxation, or bowstringing, of the flexor tendons secondary to digital fibro-osseous rupture. The sublimis was functionally intact on clinical examination.

is also confirmatory for medial epicondylitis. Anterior elbow pain and tenderness implies brachial is insertional tendonopathy.ll4 1 Shoulder injuries specific to climbers are encompassed under the diagnoses of rotator cuff tendonitis, subacromial impingement syndrome and, rarely, rotator cuff, rhomboid, latissimus dorsi or lower trapezial strains. The strains are diagnosed by their localised tenderness, oedema, occasional ecchymosis and associated weakness. Rotator cuff tendonitis and subacromial impingement syndrome have similar symptoms and physical findings but different aetiologies. Rotator cuff tendonitis, like tendonitis in the elbow or forearm, can occur secondary to chronic and/or acute overuse. Microtrauma, frank tears and ischaemic injuries can occur in and around the supraspinatus and fellow rotator cuff muscles (including the long tendon of the biceps brachii). The fact that climbers spend a great deal of their time with their arms flexed high above their heads imposes further risk to the rotator cuff secondary to mechanical impingement of the cuff tendons against the acromion. Direct tenderness to palpation over the supraspinatus insertion with the humerus extended and internally rotated (Subacromial Push-button and Dawbam's tests)[151 is the most reliable indication of rotator cuff pathology. Pain and weakness Sports Med 1997 Apr: 23 (4)

Rock Climbing Injuries

to the initial 10 to 20° and last 90 to 110° of humeral elevation, particularly with humeral internal rotation (supraspinatus arc test) and pain with the impingement manoeuvre (humeral internal rotation followed with flexion and adduction across the face) are supportive of the diagnosis.

6. Treatment and Prevention The major cause of most sport climbing injuries is over-training; prolonged frequent climbing bouts and failure to rest injuries. Muscle imbalance and 'de-conditioning' can account for most of the other injuries. The long finger flexors, the flexor digitorum profundus and flexor digitorum sublimis, as well as the extensor carpi radialis brevis and biceps brachii are muscle units that cross 2 or more joints. The total passive excursion in these muscle/tendon complexes can be less than that necessary for the maximum combined passive motion in the joints they cross. Chronic gripping and pulling without stretching, and failure to exercise the antagonists, can lead to relative overdevelopment of these muscles, as well as contractures, as the muscles reset their functional length: 'deconditioning'. This shortening and tightening of the active muscle groups make them more prone to strain injuries. Overuse of muscle groups will not give the muscle-tendon, muscle-bone and tendon-bone junctions time to adapt to the added loads. Similarly, the synovial sheaths at the flexor retinaculums in the wrist and fingers will have insufficient time to adapt to the added mechanical and frictional forces. Tenderness, oedema and pain are warning signs. They should be respected early rather than 'worked through'. Climbing, particularly in the new climber, should be limited to the tolerances of the individual's body, both in duration and difficulty. These injuries are easier to prevent than to cure. Endurance, low-weight and high-repetition, fullrange weight training, such as dumb-bell wrist curls, should be encouraged. There should be a minimum 24-hour rest period between weight training sessions Lo allow the body time to repair itself. Major work-outs, including climbing, require © Adis International Limited. All rights reseNed

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48-hour recoveries. Work-outs should be preceded by gentle stretching and followed by more vigorous stretching. Rotator cuff strengthening should emphasise the initial humeral abduction arc (0 to 30°) as well as internal, and particularly external, humeral rotational exercises. Isometrics and resistance training are equally applicable. Stretching is just as important here as in the forearm and hand. Once tendonopathies become established, treatment will be more difficult. Cessation of climbing often produces quick relief. This relief however quickly disappears, and symptoms are often worse, on return to climbing. Therefore, a rehabilitation programme that includes climbing should be established. Difficulty, length and frequency of climbing should be decreased. At first daily stretching should be implemented for 2 to 4 weeks. This is followed by low-weight, full-range resistance exercises to the injured complex, with repetitions of 10 to 15 and I or 2 sets. This is slowly increased as tolerated to 20 to 30 repetitions and 3 sets. Small muscle groups can be worked daily, whilst larger groups should be exercised every 48 hours. Stretching should be continued and antagonist muscle groups also exercised. Standard modalities, with heat before, and ice after, exercise programmes are useful. A minimum of 2 to 3 months of rehabilitation is to be expected. Changes in climbing behaviour as noted below may be indicated. PIP contractures, sublimis insertional strains and digital fibro-osseous ruptures are a much more serious problem. Permanent fixed PIP joint contractures and eventual arthroses may result. Fixed PIP joint contractures should be aggressively treated with dynamic PIP extension splinting and, if resistant, serial casting. Treatment for 6 months to a year or for as long as the patient climbs should be expected. Anecdotal evidence suggests that the digital fibro-osseous sheath can be at least partially protected by digital taping of the proximal and middle phalanges. Suspected partial sublimis ruptures should be treated as partial tendon lacerations. Once injuries occur in the PIP joint region, Sports Med. 1997 Apr; 23 (4)

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a change in climbing behaviour appears prudent as permanent damage is highly likely. The common crimp grip of sports climbing (see fig. 5b) should be avoided. Redirecting the sports climber to natural rock faces emphasising hand and fist width cracks or faces that emphasise foot work may be helpful. Acceptance of permanent PIP joint damage as the price of climbing and an attempt to minimise this damage often becomes the only option. Surgical reconstruction of the fibro-osseous sheath or sublimis is usually contraindicated because of the necessary compliance with a 3- to 6-month postoperative regimen with no climbing to prevent re-rupture.

7. Conclusions As the sport of rock climbing increases in popularity, more physicians will be confronted with the treatment of these athletes. Surgery will rarely be indicated, and prolonged (3- to 6-month) rehabilitation programmes will be the norm. Treatment principles for tendonopathies are applicable in prevention and treatment. Stretching and strengthening of the digital extrinsic flexors, the shoulder cuff muscles and the wrist extensors are indicated. Antagonists should also be exercised. Climbing periods should be limited and climbers convinced to allow enough time (48 hours) for recovery between work-outs. Early PIP joint symptoms indicate the need for digital taping and training changes. Evidence of sublimis insertional strain, digital fibroosseous sheath rupture or PIP joint contracture are signs warning of permanent injury.

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References I. Mountain Climbing, The 1996 Grolier Multimedia Encyclopedia on CD-ROM. Danbury (CT): Grolier Electronic Publishing Inc .• 1996 2. Long J, How to rock climb. Evergreen (CO): Chockstone Press, 1989: 54-5 3, Long J, How to rock climb, Evergreen (CO): Chockstone Press, 1989: 4-14 4, Wilson R, Mills, Jr WJ, Rodgers DR, et al. Death on Denali, West J Med 1978; 128: 471-6 5. Adler J, Norland R, High risk, Newsweek 1996; May 27: 50-8 6. Bowie WS, Hunt TK, Allen, Jr HA. Rock-climbing injuries in Yosemite National Park. West J Med 1988; 149: 172-7 7. Rooks MD, Johnston RB III, Ensor CD, et al. Injury patterns in recreational rock climbers, Am J Sports Med 1995; 23: 6: 683-5 8. Shea KG, Shea OF, Meals RB . Manual demands and consequences of rock climbing. J Hand Surg Am 1992; 17 A (2): 200-5 9. Bollen SR. Upper limb injuries in elite rock climbers , J R Coli Surg Edinb 1990; 35 Suppl.: s18-20 10, Bollen SR, Soft tissue injuries in extreme rock climbers, Br J Sports Med 1988; 22 (4): 145-7 II, Bollen SR, Gunson GK , Hand injuries in competition climbers, Br J Sports Med 1990; 24 (I): 16-8 12. Brand PW, Hollister A, Mechanics of individual muscles at individual joints, In: Brand PW, Hollister A, editors, Clinical mechanics of the hand, SI. Louis (MO): Mosby-Year Book Inc " 1993: 254-352 13, Robinson M. Medicine: Snap, crackle, pop. Climbing 1993; 138: 141-50 14, Gerard JA, Kleinfield SL. Elbow testing. In: Gerard JA, Keinfield SL, editors. Orthopaedic testing, New York: Churchill Livingstone, 1993: 147-74 15, Gerard JA, Kleinfield SL. Shoulder testing. In: Gerard JA, Keinfield SL, editors, Orthopaedic testing, New York: Churchill Livingstone, 1993: 87-142

Correspondence and reprints: Dr Michael Rooks, Department of Orthopaedics, Suite 3101,20 Linden Avenue, Atlanta, GA 30308,

USA.

Sports Med, 1997 Apr; 23 (4)