Shoulder Injuries And Sport

Chapte r8Shoulder 

 

injuries    

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Introduction

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Anatomy and biomechanics

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Instability

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Anterior instability

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Acute dislocation

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Recurrent dislocation

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Multidirectional instability

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Posterior instability

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Posterior subluxation

Tendinitis and impingement ○

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Rotator cuff tears

Internal derangements within the glenohumeral joint ○

Labral tears , SLAP lesions, loose bodies

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Acromioclavicular joint dislocation / fractures

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Clavicle fractures

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Outer clavicular osteolysis

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Medical clavicular sclerosis

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Sternoclavicular dislocation

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Muscle ruptures

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Biceps tendon injuries

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Nerve injuries - suprascapular

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Other conditions

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Prevention of injury to the shoulder

1 D. Bokor The Shoulder in E Sherry and D Bokor (eds). Manual of Sports Medicine. GMM London 1997.

 

Introduction Because of its great mobility and intrinsic instability the should is the most vulnerable joint to injury in the body. It is required to provide a large range of movement with speed and force so the athlete can provide a top performance. We were never intended to be involved in all this above shoulder activity. Therefore little surprise that this joint is prone to a variety of injuries from the stresses being applied to the bones, chondral surfaces and the soft tissues. 8 -13 per cent of injuries sustained by athletes involve the shoulder. Anatomy and biomechanics The shoulder function consists of four separate joints-the glenohumeral joint(the main one), the acromio-clavicular, sternoclavicular joints and scapulo-thoracic. Disorders of any one of these may manifest as a dysfunction of the glenohumeral joint. The glenohumeral joint (GHJ) is a ball and socket joint. The humeral head comprises about one third of a sphere. The articular surface has a medial angulation of 45 degrees to the shaft and is retroverted about 30 degrees. The glenoid fossa is pear shaped (radius of curvature is half that of the humeral head and so the area of bony contact is small). The glenoid labrum increases the depth of the fossa and increases the contact area of the humeral head and the glenoid. Ligamentous stability is supplied by the superior (major stabilizer) middle, and inferior glenohumeral ligaments and the capsule (Further stability from negative intra-articular joint pressures, the rotator cuff muscles and the coracohumeral ligament(Fig1) The acromioclavicular joint (ACJ) is a diarthrodial joint which links the arm to the axial skeleton. There is little inherent bony stability. It has a variable fibrocartilaginous disc/meniscus. The capsule and the superior acromioclavicular ligaments stabilizes at physiological loads. Along with the coracoclavicular ligaments. the conoid and trapezoid. The sternoclavicular joint (SCJ) has two incongruent articular surfaces with fibrocartilaginous disc forming two independent joints. It is stabilized by the interclavicular, anterior and posterior sternoclavicular ligaments and the costoclavicular ligament (rhomboid ligaments). The joint has three planes of motion. (The fulcrum is the rhomboid ligament, not the SCJ articulation.) Despite the low weight of the arm, (5% of body weight, i.e. 3.6 in a 72 kg man) high torque forces are generated by its long lever arm. The rotator cuff and other shoulder muscles generate movement and glenohumeral control. In throwing all the muscles of the trunk and upper limb work in a synchronized balanced manner to propel an object forward. Throwing action is divided into: cocking (or wind-up), acceleration and follow-through phases. Imbalance, fatigue, or damage to these structures may result in pain, tendinitis and/or instability (Fig.2).

Instability Shoulder instability is common in sport. Apart from a frank, dislocation a wide range of symptoms result from variable degree of slipping of the shoulder. Partial dislocation is referred to as subluxation. This is not an insignificant injury to the glenohumeral joint, severe injuries occur from subluxed joints. These are ‘instability events’ (and potentially damaging to the joint), (95%) of shoulder instability is anterior/antero-inferior direction (other, directions include posterior/multidirectional.) Anterior instability Occurs when the arm is in abduction/external rotation and an anterior force applied on the shoulder joint, (fall on the outstretched hand or tackling a player with the arm out from the side, (rugby). May occur without an obvious traumatic event. Overhead sports, (baseball or tennis), cause a gradual stretch of the anterior capsule and symptoms of the shoulder slipping. Note hierarchy of support mechanisms controlling glenohumeral stability and so cascade of injury (see Table 1).  

 

 

Table 1

Minimal Loads Moderate Loads Massive Loads Symptoms of instability include: frank dislocation; slipping; pain with the arm in abduction/external rotation; apprehension when using the arm overhead or a ‘dead arm’ feeling with a tackle or overhead action. Clinical examination check ROM, strength, increased antero-posterior translation of the humeral head (Fig. 3) apprehension(Fig4) and relocation signs, note coincident tendinitis or labral tears and also signs of ligament laxity. (Hyper extend knee, elbow, MCP joints hand; flex wrist so hand touches forearm). The natural history1 of the first acute anterior shoulder instability is now known. Recurrence young patient (less than 22 years of age) is 62% (if participate in contact sports repeat instability is over 90%); Older patients (in 30-40 years old patients 25%). Over ten years period there is a 12% chance of a contralateral instability and a 20% incidence of arthritic changes on x-ray (9% moderate or severe). This arthropathy is thought not to be influenced by the number of dislocations or whether surgery has been performed. Acute dislocation Assess for any nerve or vascular injury x-ray the shoulder (AP + lateral in plane of scapula). Closed reduction can be performed in the emergency room using either Pethidine (50-100 mg IVI) Diaepham (5mg IVI) Nitrous2 oxide (entinox : 50% nitrous oxide / oxygen) or with an intraarticular injection of lignocaine 1% (5cc). General anaesthesia may be required where there is

 

 

 

excessive muscle spasm (or young male with huge shoulder muscle girdle). Techniques for Closed Reduction of the Dislocation Shoulder are described. Below (Table 2). The arm should be placed in a sling and physiotherapy organized after a 1 - 3 weeks. Younger patients have a high risk of recurrence; so for special sporting requirements consider an acute arthroscopic assessment and capsular/labral repair.

1 L. Hovelius 1987. Anterior dislocation of the shoulder in teenagers and young adults: five year prognosis. JBJS 69a, 393-399. 2 E Sherry A Henderson J Cotton 1989. Comparison of Midazolam and diazepam for the reduction of shoulder dislocations and Colles’ fractures in skiers on an outpatient basis. Aust. J. Sci Med. Sport.

Recurrent dislocation If recurrent instability becomes a problem, options include: modification or avoidance of the precipitation event, a physiotherapy rehabilitation programme to strengthen the shoulder; or surgical reconstruction of the shoulder. Several of surgical techniques are used based on these correcting the pathology and those which tighten or use bone blocks to avoid dislocation. Correction of the pathology (Table 3) includes repairing the avulsed inferior glenohumeral ligament (Bankart lesion) and correcting any associated capsular redundancy (capsular shift) (preferred option in surgical management of the unstable shoulder). The success rate for surgery is 95%. Procedures which correct the pathology (i.e. anatomical reconstruction) are more likely to restore full range of motion. Especially for those involved in upper limb sports (requiring a throwing action e.g. baseball). Many of the non-anatomical reconstructions restrict external rotation and so restrict athletes. Types of shoulder reconstruction are described below. Multidirectional instability (MDI) Most shoulders show a variable degree of laxity (and is normal) where marked laxity this may become a problem. This may be insidious in onset or be related to a trauma. Important to differentiate laxity from stability. Laxity is a physical finding, whereas instability is the combination of symptoms and signs. The diagnosis of MDI, is based on finding least two directions (inferior plus either / or both anterior and posterior.) Patients have pain and weakness associated with a shoulder that subluxes inferiorly as well as anterior and posterior. Take care in the evaluation of these patients. A small subgroup of MDI patients demonstrate a habitual / voluntary aspect to their problem. This group of patients should be evaluated for associated psychological problems and potential secondary gains. Surgical procedure will fail in this group.

Treatment focuses around rehabilitation. (Strengthening of the rotator cuff and scapula stabilizers, proprioceptive/biofeedback techniques and modification of activities.) Most will respond to physiotherapy. If necessary, surgery will include an inferior capsular shift with closure of the rotator capsular interval and tightening of the superior glenohumeral ligament. The results of surgery are 80-90% good. Table 2. Techniques for Closed Reduction of the Dislocated Shoulder  

   

 

Table 3. Types of shoulder reconstructions

 

Anatomical    

 

 

1 W J Mallon 1993. Shoulder instability. In Frymoyer (ed) OKU 4. AAOS. Rosemont Il. p297-302.

Non-Anatomical Reconstructions

 

 

 

  Posterior instability Posterior dislocation is uncommon (4% of all dislocations). Occurs from a fall; or violent muscle contractions as in an electrocution or grand mal convulsion. The diagnosis is often delayed or missed. There is pain and the arm is locked in internal rotation. The (antero-posterior) X-ray may look normal but beware check the axillary view (is diagnostic). If there is any doubt then a CT scan should be performed.] Posterior subluxation Posterior subluxation can occur from sports such as baseball. Suspect when the athlete experiences symptoms with the arm in front of the trunk. May then be associated with multidirectional instability. Clinical examination may reveal increased posterior glide, and symptoms reproduced on degrees forward flexion (Fig. ). The posterior load of the shoulder in 90 X-rays are often normal. If there is a ‘locked posterior dislocation’, early recognition and reduction is essential. If the dislocation is long standing or a large portion of the humeral head damaged then open reduction with surgical reconstruction of the humeral head defect (by autograft, allograft or tuberosity transfer) is required. Where chondral damage has occurred, total shoulder replacement may be necessary. In patients with posterior subluxations and associated multidirectional laxity, an intensive physiotherapy rehabilitation programme is required. Most patients will respond to this. If stability continues then surgical reconstruction is necessary (performed from an anterior or posterior

approach). Anterior surgery consists of an inferior capsular shift and tightening of the superior glenohumeral ligament. Posterior reconstruction undertakes an inferior capsular shift only. In both cases the patient is immobilized in a neutral rotation brace for 6-8 weeks then placed on a graded rehabilitation programme extending over twelve months. No return to sports at least twelve months. Tendinitis and impingement The supraspinatus is vulnerable to inflammation as it passes under the coraco-acromial arch in the crowded space between the arch and the greater tuberosity. Tendinitis of the rotator cuff may occur from overload/fatigue of the cuff tendons, trauma, age related degenerative changes. The acromion may have a shape which increases the crowding of the cuff tendons here which leads to impingement Note: Tendinitis may occur in patients with very lax shoulders (the muscles are overworked to stabilize the humeral head). Therefore, it is important to beware of tendinitis in these patients (younger than 25 years) as this may be secondary to subtle (unrecognized) instability. Typically there is pain over the anterior aspect of the shoulder with radiation into the deltoid (minimal at rest and rarely radiates down the arm or into the neck; aggravated with overhead and rotation activities). Night pain with waking indicates severe cases. Examination, tenderness is located over the greater tuberosity. Impingement signs are present (Fig 6 ). Biceps (tendinitis) provocation test may also be positive (Speeds test-pain with resisted forward elevation of strength arm; Yergason’s- pain with resisted supination of the flexed elbow). The Acromioclavicular joint may be involved. Range of motion and strength are often normal, wasting does occur early. There is pain on loading the rotator cuff muscles. Weakness is due to inhibition from pain. Exclude cervical conditions which may refer pain into the shoulder; (where cervical irritation the shoulder posture is in a depressed or elevated position.) The diagnosis of tendinitis is a clinical diagnosis. A plain X-ray is essential (include a supraspinatus outlet view) Next investigation is the impingement test. (5-10 mL of lignocaine is injected into the subacromial bursa, wait five minutes, there is then a significant decrease in pain on forward elevation of the arm to perform the impingement sign (Fig. 6). Ultrasound (in experienced hands) accurate in diagnosing full-thickness tears and impingement. Note all shoulders which are stiff, as in adhesive capsulitis, will show impingement on ultrasound due to tightness of the posterior capsule limiting the inferior glide to the humeral head, therefore, investigations should be considered in their clinical context. Arthrography will show cuff tears. Treatment includes activity modification, NSAIDs and physiotherapy (consisting of stretching and strengthening of the rotator and scapular muscles). Most cases respond. If pain persists inject corticosteroid and local anaesthetic (½ ampoule celestone with 5mls 0.5% marcaine plain) into the subacromial space both diagnostic, and therapeutic. If conservative treatment doesn’t help after 6 months, then acromioplasty (open or arthroscopic) is successful in 90% (Fig. 26).

Rotator cuff tears Normal tendons seldom tear. For young patients if required a violent injury (instability of direct trauma) to tear the cuff. For older patient there is underlying degenerative changes in the rotator cuff so less trauma is required to disrupt it. With repetitive overhead use of the arm, (tennis or baseball), micro damage to the cuff can progress to a full-thickness tear. The symptoms are similar to tendinitis. Pain is worsened by overhead activities, and at night. Weakness is present (however with full-thickness tears often there is a normal active range of motion). Only massive rotator cuff tears lose active range of motion. The long head of biceps may be torn as well. Perform x-rays (may show an acromial spur and narrowing of the acromiohumeral gap where the tear is large) may need an arthrogram, ultrasound or MRI to confirm the diagnosis, extent of damage, atrophy of muscles and associated joint disease (note ultrasound is usually sufficient and cost effective). Treatment in the young patients (less than 50 years) surgery (with acromioplasty and rotator cuff repair) is required as there is a risk of increase in tear size and deterioration of shoulder function. In older patients a short trial of activity modification, NSAIDs, physiotherapy and corticosteroid injection is reasonable. If pain then surgery with acromioplasty and rotator cuff repair is indicated. Internal derangements within the glenohumeral joint Labral Tears, SLAP (Superior Labral Antero/Posterior) lesions, loose bodies. Caused by trauma, direct or in association with instability. The labrum, most developed in the upper part of the shoulder joint tears here and may extend into the biceps anchor. Known as SLAP (Superior Labral Anterior Posterior) lesions, four types (frayed labrum / also detached biceps / detached superior labrum / also into biceps anchor). Loose bodies arise from trauma or synovial disease (synovial chondrometaplasia). There is pain with sudden motion, clicking or catching (with rotation). Pain is worse with resisted elevation of the arm while forward flexed (90 degrees and slightly adducted with the hand in internal rotation. When the hand is externally rotated in the same position then the pain decreases. There may also be associated features of instability. Diagnoses is difficult1 and requires investigation. (Such as MRI with gadolinium enhancement, or arthroscopy). The treatment is often arthroscopic with either resection or repair of the torn labrum and removal of loose bodies. Also important to treat the underlying cause (such as instability). 1 C A Rockwood, F R Lyons 1993. Shoulder impingement syndrome: diagnoses, radiographic

evaluation and treatment with a modified Need acromioplasty. JBJS 75A 409 - 424. Acromioclavicular joint injuries The acromioclavicular joint (ACJ) commonly injured from a fall onto the point of the shoulder. 1 The injury is chondral or meniscal. More severe injuries result in subluxation or dislocation of the joint. Classified as sprain, subluxed (coraco-clavicular lig. intact),or dislocated (coraco-clavicular ligament torn). On examination, localized tenderness and swelling is seen. In dislocations the outer clavicle appears superiorly displaced, (actually the shoulder that sags below the clavicle). Forced cross body adduction provokes discomfort. X-rays of the joint should include standing weighted views of the ACJ with the weight to the wrists of the patient . For undisplaced injury ice, rest and then gradual return to activity over a 2-6 week period is required (note that seemingly minor ACJ injuries may give rise to grumbling discomfort for up to six months). Major dislocations may require surgical stabilization in athletes if their dominant arm is involved, and if they participate in upper limb sports or awe workers who use their arms overhead. Clavicle fractures Common injury occurs from a fall onto the outstretched hand. Fractures occurs in the mid-shaft, (also medial or lateral possible). There is pain, swelling and deformity over the site of the fracture. Neurological lesions are rare (brachial plexus) as are vascular injuries. The majority will go on to union with little morbidity, even when moderate shortening or angulation (the bone ends only need to be on the same room). Some may develop symptoms with cross body actions if the clavicle is too shortened. (If the fractures are lateral and involve the Coracoclavicular ligaments or AC joint, treatment may require surgical fixation of the outer clavicle). Most fractures are treated with a sling for elbow support. Clavicle rings to pull shoulders back may help and stabilize the fracture ends). Take care to avoid skin pressure problems and axillary neurovascular compression. With marked displacement or shortening, early open reduction and internal fixation may be considered (but rarely). Outer clavicular osteolysis2 Occurs from a direct blow or fall, may develop in athletes who work out in the gymnasium on overhead machines or in overhead sports. Probable pathology is a chondral or minor osteochondral fracture which triggers an inflammatory response, leading to resorption of the outer clavicle.

There is pain over the AC joint (radiates to the deltoid or base of neck). Examination reveals localized tenderness and swelling over the AC joint, advanced cases a palpable gap is present at the AC joint. X-rays show irregularity of the outer clavicle with osteolysis (‘suck-candy’ appearance). A bone scan, (not always necessary) will be hot. Treatment is rest, activity modification and NSAIDs. If the pain is severe then surgical excision of the outer clavicle is required.

1 R R Richards 1993 Acromioclavicular joint injuries. Instr. Course Lect. 42,259-269. 2 M Scarenius, B F Iverson 1992. Non traumatic clavicular osteolysis in weight lifters. Am J Sports Med. 29 463 467

Medical Clavicular Sclerosis (Osteitis Condensans) A rare disorder where there is osteosclerosis of the medial end of the clavicle. Aetiology is unknown, (low grade osteonecrosis or osteomyelitis proposed, but never proven). Occurs in middle aged females with a long insidious onset of pain and discomfort (with elevating the arm). X-rays show mild enlargement and sclerosis of the medial end of the clavicle (no bone destruction or periosteal reaction). Confirmation by CT scan (though MRI useful). Treatment is non-operative (analgesics and NSAIDs). May be symptomatic for many years. Condition is rarely painful enough to warrant surgical excision. Sternoclavicular dislocation Although limited ligamentous support of the inner end of the clavicle exists, dislocations are rare. May be anterior or posterior. Usually occurs from a fall onto the side and from compression of the shoulder from another player falling on top. Anterior dislocation displays a painful prominence of the medial end of the clavicle. Reduce closed in the acute situation (many surgeons prefer to leave the dislocation and treat the patient symptomatically). The diagnosis is confirmed with a CT scan as X-rays of this region are difficult to read. A posterior dislocation may cause pressure on vital structures in the neck with dysphagia, dyspnoea or great vessel compression. A surgical emergency. Posterior dislocations should be reduced urgently if there is compromise of the thoracic outlet mediastinal structures. Place a bolster between the shoulder blades and apply posterior pressure to the shoulders. If the clavicle doesn’t so reduce around the clavicle and pulled forward to reduce hook a sterile

surgical towel clip. Muscle ruptures A number of muscles may rupture about the shoulder, including pectoralis major; long head of biceps and subscapularis. A muscle tears when there is contraction against an unexpected resistance. Weight lifters (bench pressing large weights) incur such injuries. When the arm is in 90 degrees of abduction and in extension the subscapularis may tear. There is severe pain and a tearing sensation (at the time of rupture), followed by swelling and bruising. The torn Pectoralis Major bunches on contraction. Long head of biceps rupture may be associated with rotator cuff disease. Subscapularis rupture is to pick (Note: weakness on the posterior lift-off test not able to move back of hand off sacrum). For the ruptured pectoralis muscle surgical repair is necessary, as the athlete will notice deformity and weakness. A subscapularis tear there may cause term changes in rotator cuff balance and function; so repair is recommended.

1 B L Berson 1979. Surgical repair of the pectoralis major rupture in an athlete. AMJ Sports Med. 7, 348-351.

Biceps tendon injuries The biceps may be injured with anterior instability or inflamed with impingement and rotator cuff tears. 95% biceps tendonitis secondary. There is pain over the anterior shoulder. Examination pinpoints tenderness in the biceps groove. A click from subluxation of the tendon may occur with rotation of the arm. Treatment is rest NSAIDs and steroid injections in the biceps groove. If pain persists or there is dislocation of the biceps then surgical tenodesis is required. If the long head of biceps ruptures the pain often subsides. The rupture is treated symptomatically and surgery rarely required. Nerve injuries Nerve injuries about the shoulder occur from direct trauma, traction, compression or instability. The nerves may sustain a neuropraxia or division. Nerves involved include the axillary, suprascapular, musculocutaneous, long thoracic (in swimmers scapulas winging, thoracolumbar brace with scapular pad may help) and radial nerve. A brachial plexus palsy (partial or complete) occur with high energy trauma (burners/stingers, transient, foot ball; root avulsions carry poor prognosis). Thoracic outlet is compression of nerves/vessels between scaleres and first rib. Abnormal scaleres or cervical rib. C8-T1 signs. Wright test (Arm is extended/abducted/externally rotated; head turned away; postpone where symptoms / no pulse.

Improve posture rarely surgery. There is pain related to the injury and weakness. Careful neurological examination is required to localize the injury. Usually the injury is a neuropraxia and will recover. EMG studies may ascertain whether the lesion is complete and /or recovering. Exploration and repair of the nerves is indicated if the lesion does not recover within six months. If suprascapular nerve compression is evident then an MRI scan may reveal a spino-glenoid notch ganglion cyst pressing on the nerve. (Surgical excision / release transverse suprascapular ligament). Other conditions Scrapping scapula - from irritation of periscapular bursae, maybe voluntary, difficult to treat, NSAIDs, inject or partial distal scapular resection. Adhesive capsulitis (frozen shoulder synovitis with capsular contraction), painful should with global ROM (end stage inflammation; exclude post dislocation shoulder / OA neck), autoimmune problem, after trauma or immobilization onset in stages, x-ray shows osteopaenia. Needs NSAIDs. physiotherapy, steroid injection and MUA. Calcific tendinitis - deposition of calcium (toothpaste) in supraspinatus tendon in middle-aged women, pain in the resorptive phase, localized deposit on x-ray, may benefit from needling/steroid injection or surgical excision (including bursoscopy). Prevention of injury to the shoulder Very important to have a general condition programme. In upper limb activity sports the programme includes muscle strengthening and stretching about the shoulder and scapula. Such appropriate strength and muscle length allows for optimal muscle function. Prior to exercising warm-up is the first step. Stretching of the rotator cuff and posterior capsule and then gentle strengthening exercises focused on the rotator cuff and scapular stabilizers is important. Technique of throwing needs to be carefully developed under supervision to optimize performance without excessive undue strain on the shoulder capsule or muscles. At the first sign of fatigue or discomfort the athlete should rest to prevent any injury progressing to a more serious level. After activity the athlete should cool down the affected area and then reinstate a gentle stretching programme before rest. It is important to realize that high level performance at sport places an extreme demand on the bodies tissues and the off season is critical in allowing micro damage to heal itself (appropriate

complementary exercises are important in the off season). Such exercise should not place the same strains on the tissues but should be directed at maintaining aerobic fitness in preparation for the next season. Following this all athletes should be able to enjoy their sports for many seasons with a minimal risk of injury.