Due to its complex anatomy and the difficulty in eliciting reliable clinical diagnostic signs, the evaluation and treatment of biceps shoulder pathology has always been a challenge for orthopaedic surgeons. The role of the long head of the biceps tendon in shoulder pain and disability has been debated for more than 100 years, almost since the original description of periarthritis by Duplay in 1872. In 1942 Hitchcock and Bechtol believed that biceps tendonitis was a primary source of shoulder pain and described a soft tissue tenodesis for definitive treatment. In 1972 Neer revolutionized the approach to shoulder pain in his classic description of impingement syndrome. According to Neer, in most patients, the primary source of shoulder pain is impingement, and biceps tendonitis is a secondary development. This paper aims to try and answer a few questions, what is the role of the biceps tendon? What is the pathogenesis of biceps tendon pathology? What treatment options are available and how successful is each option?
Anatomy and function
The Long Head biceps tendon originates from the labrum and the supraglenoid tubercle of the scapula. The structure is intraarticular yet extrasynovial. It is widest at its origin and progressively narrows as it exits the bicipital groove. The proximal one-third of the biceps tendon has a high degree of innervation, with substance P and calcitonin gene-related peptides present, suggesting a rich sympathetic network. The proximal portion of the long head receives its blood supply primarily from the anterior circumflex humeral artery. The biceps tendon passes posterior to the coracohumeral ligament and beneath the transverse humeral ligament as it courses distally. The capsuloligamentous structures of the rotator interval are responsible for restraining the biceps tendon within its proper anatomic location as it passes into the bicipital groove. The coracohumeral ligament and the superior glenohumeral ligament are the two most important structures within the rotator interval for securing the biceps tendon. The superior glenohumeral ligament forms an anterior sling about the biceps. The more distal transverse humeral ligament is not believed to play a primary role in securing the biceps tendon.
The biceps tendon (BT) makes a 30° to 40° turn into the bicipital groove as it exits the shoulder and is stabilized by a pulley system2. CHL = coracohumeral ligament and SGHL = superior glenohumeral ligament.
With the shoulder stabilized, the function of the biceps is flexion of the elbow and supination of the forearm. The exact function of the long head of the biceps tendon in the shoulder is controversial. It is usually described as a weak flexor of the glenohumeral joint. The angular orientation of the biceps relative to the humeral head appears to be adaptive in nature, and it diminishes the capacity for arm elevation, perhaps placing the biceps at risk for instability. The proximal part of the biceps tendon probably has at least a passive shoulder stabilizing function. Whereas several authors have observed that the proximal part of the biceps tendon has an active stabilizing effect, others have not. Cadaveric biomechanical evidence indicates that the contribution of the biceps to glenohumeral stability may depend on the position of the elbow.
Problems related to the biceps tendon can be classified as inflammatory, instability, or traumatic. Bicipital tenosynovitis is closely associated with impingement. Neer demonstrated that the biceps tendon is subject to the same mechanical wear beneath the coracoacromial arch as is the rotator cuff. Because the biceps tendon sheath is continuous with the glenohumeral joint, any inflammatory process affecting the intra-articular environment can also affect the biceps. Biceps instability may occur more commonly than would be expected on the basis of clinical and arthroscopic examinations. Medial subluxation or dislocation of the tendon can occur with repetitive wear or trauma to the restraining structures and is commonly associated with rotator cuff lesions, especially subscapularis tears. Finally, while traumatic biceps tendon lesions including rupture are uncommon, other traumatic disruptions such as SLAP lesions do occur.
Medial subluxation or dislocation of the biceps tendon (BT) can occur with repetitive wear or trauma to the superior glenohumeral ligament (SGHL) and is commonly associated with rotator cuff disease, especially subscapularis tears (SSC) as well as supraspinatus (SSP) tears.
Differential Diagnosis of Shoulder Pain
Numerous tests exist for diagnosing biceps tendon pathology, however these tests often provide inconsistent and misleading results.
The patient flexes the shoulder against resistance with the elbow extended, arm flexed to 90o and the forearm supinated, pain is noted in the arc of the biceps groove.
With the elbow flexed, the patient supinates the forearm against resistance. Pain referred to the proximal aspect of the groove is a positive finding.
Compression rotation test
Performed with the patient supine and the arm abducted 90°. With the patient’s elbow flexed 90°, an axial load is placed on the shoulder as it is circumducted and rotated (similar to the McMurray test of the knee). The test is considered positive if there is a click or pain with compression.
Anterior slide test (described by Kibler)
The patient’s affected arm is positioned with the hand on the hip with the thumb forward; the examiner then stabilized the shoulder with one arm and used the other arm to place an anterosuperiorly directed axial load on the humerus. The test is considered positive if there was a click or pain deep in
The Active compression test (described by O’Brien et al)
With the patient standing, the patient’s affected arm is flexed forward 90° and adducted across the body 10°, with the thumb pointing down. The patient is then directed to resist a downward motion by the examiner and asked to localize any pain deep in the shoulder. The test is then repeated with the arm in the same position but with the palm of the hand pointing upward. The test is considered positive if the original pain is eliminated.
Multiple studies have been done to determine the accuracy and reliability of these tests, but most studies show a low sensitivity and positive predictive value.
AP, LAT, supraspinatus outlet view and a biceps groove view may be helpful.
Various reports claim 91% sensitivity and specificity in detecting rotator cuff tears. They also claim that ultra sound is better than arthrography for the evaluation of the biceps tendon.
Arthrography can be useful, however the sheath often fails to fill with contrast, especially in patients with associated rotator cuff tears.
Magnetic resonance imaging is an excellent tool for evaluating the biceps tendon and the superior labral complex. A magnetic resonance imaging arthrogram continues to be the most appropriate noninvasive diagnostic study available for confirming a pathological condition of the biceps. Oblique and sagittal images can demonstrate subluxation and dislocation of the long head of the biceps tendon. Edema associated with bicipital tendinitis produces increased signal intensity on T2-weighted images. Biceps tendon ruptures are relatively easy to detect on magnetic resonance imaging.
Biceps Tendinitis and Instability
Biceps tendinitis is a relatively common cause of anterior shoulder pain. The tendinitis can be primary or secondary. Primary bicipital tendinitis is the isolated inflammation of the long head of the biceps tendon in the intertubercular groove, with no associated pathological changes in the shoulder. It has been estimated to represent only 5% of the cases of biceps tendinitis. Secondary biceps tendinitis occurs in conjunction with pathological changes in the adjacent osseous, ligamentous, and muscular structures (mainly seen in conjunction with impingement syndrome). This type of tendinitis often results in tendon fraying and even failure as the biceps tendon undergoes wear. As a result of repetitive wear or trauma, the soft tissue restraints surrounding the biceps tendon can lose their stabilizing function, and medial subluxation or dislocation of the tendon can occur.
Boileau et al. described an hourglass-shaped biceps tendon that causes typical tendinitis symptoms. It results from an inflamed, thickened intraarticular segment, which can block tendon excursion during shoulder motion because the thickened part cannot traverse the bicipital groove. This so- called shoulder trigger finger can cause anterior shoulder pain and a loss of 10° to 20° of passive elevation as a result of mechanical locking, but it is difficult to recognize clinically. A thickened tendon can disrupt the pulley and destabilize the biceps over time. .
Damage to the pulley system of the long head of the biceps often occurs in a series of steps and is usually initiated by an articular-sided supraspinatus tear, which then leads to a tear of the superior glenohumeral ligament. The tear of the superior glenohumeral ligament in turn allows subtle subluxation of the long head of the biceps, which can, in turn, cause a partial articular subscapularis tear. Progressive subluxation of the long head of the biceps causes more damage to the subscapularis tendon. This cycle of progressive subluxation leading to subscapularis damage can ultimately lead to medial dislocation of the biceps and even anterosuperior instability with the occurrence of labral lesions.
Treatment of Biceps Tendinitis
The initial treatment of primary and secondary bicipital tendinitis is non- operative. Initially, rest and non-steroidal anti-inflammatory drugs are recommended. Subacromial steroid injections can help to treat both primary and secondary tendinitis. Injections into the glenohumeral joint can reduce intra-articular biceps irritation. Finally, injections into the bicipital sheath anteriorly, with care taken to avoid the biceps tendon itself, can be of benefit. Once the symptoms begin to decrease, gentle range-of-motion exercises are begun.
The most important aspect of treating a pathological condition of the biceps tendon is to determine its cause, define the degree of structural compromise, and detect associated pathological conditions, such as rotator cuff disease and impingement that needs to be addressed concomitantly. Surgical intervention for biceps tendinitis is generally indicated if the patient continues to have symptoms after three months of conservative management or if there is biceps instability. The surgical options available include tendon débridement, a release of a constricted synovial sheath, a tenodesis, or a tenotomy.
There is controversy surrounding the choice between tenotomy and tenodesis. The decision regarding treatment of an inflamed but otherwise intact biceps tendon is not always an easy one. Tenotomy has obvious advantages; it is technically very easy to perform, rehabilitation is simple, and there is no need for immobilization. The disadvantage of a tenotomy is the potential for a residual Popeye deformity caused by retraction of the biceps muscle distally. In addition to this deformity, cramping and weakness with vigorous use of the biceps may be encountered. Clinical studies of simple tenotomies have revealed that pain relief is achieved and the satisfaction rate usually exceeds 90%, but the Popeye deformity occurs in up to 70% of patients and as many as 40% of patients experience fatigue or soreness with resisted elbow flexion. In several studies, patients over sixty years of age did not experience this fatigue. Osbahr et al. noted no significant difference in terms of the cosmetic result, pain relief, or muscle spasms between tenodesis and tenotomy, but the patients who were treated with a tenodesis were younger than those who were treated with a tenotomy. Walch et al. reviewed the outcomes of 307 patients who had had a biceps tenotomy because of an irreparable rotator cuff tear or because they were unwilling to undergo the lengthy rehabilitation associated with an arthroscopic rotator cuff repair. Eighty seven percent were satisfied, although a subacromial decompression was often performed as well.
Tenodesis can be performed either open or arthroscopically, with use of soft- tissue or osseous fixation, and above or below the bicipital groove. The advantages of a biceps tenodesis are a better cosmetic result and restoration of strength, whereas the disadvantages include a more difficult operation, the possible need for costly implants, a longer rehabilitation, a period of immobilization, and the possibility of the tenodesis failing. Several alternatives for arthroscopic fixation are available; the tendon can be secured with use of an interference screw in a bone tunnel or with suture anchors in the bicipital groove, or by suturing it to the rotator interval. Suturing the biceps remnant to the conjoint tendon has also been described. An open subpectoral approach in which a keyhole type of fixation is achieved can be utilized. Investigators comparing the mechanical strength values following tenodesis fixation techniques concluded that the interference screw and bone tunnel technique provides the greatest initial fixation strength. Tenodesis for treatment of disease of the long head of the biceps is usually performed in conjunction with the treatment of concomitant rotator cuff disease. Isolated biceps tenodesis has historically been uncommon, and the results have been modest at best, perhaps reflecting neglected underlying pathological conditions such as an impingement syndrome. Studies in which a biceps tenodesis was done in conjunction with a decompression have uniformly revealed satisfactory results, although Walch et al. reported no difference in the success rates of tenodeses done with and without an accompanying decompression. In the case of a complete biceps rupture, tenodesis is appropriate for a younger active patient and can be accomplished through an open subpectoral approach. Technically, reestablishing the proper resting length to the tenodesed biceps tendon is critical if strength and a good cosmetic appearance are to be restored. The subpectoral approach helps the surgeon to find the ruptured proximal stump and permits direct visualization so that the musculotendinous portion of the biceps can be lined up with the pectoralis insertion site to reproduce the optimal resting length. Older patients with lower functional demands have tolerated benign neglect well. Isolated pathological involvement of the biceps is uncommon, and if a rupture occurs the presence of associated rotator cuff disease should be considered.
Tenodesis using an interference screw.
The above table shows no significant difference between tenotomy and tenodesis.
Treatment of Biceps Instability
Subluxation or dislocation of the biceps tendon is almost invariably associated With a rotator cuff tear, particularly of the subscapularis, and pathological involvement of the rotator interval. The superior portion of the subscapularis tendon is usually torn and must be addressed in addition to the biceps disease. The treatment options for biceps instability include tenotomy, tenodesis, or reconstruction of the stabilizing structures that support the biceps tendon. The indications for tenotomy and tenodesis parallel those for patients with moderate-to-severe tendinitis and are the more common choices. Tenodesis of the biceps, in conjunction with a subscapularis repair, is appropriate if a patient is young and active, whereas a tenotomy is an appropriate intervention for a less active patient even when the subscapularis is being repaired. Not treating the unstable biceps definitively leads to rupture of the subscapularis repair. These anteriorsuperior tears that include the biceps and subscapularis often also involve the supraspinatus. Furthermore, careful evaluation of the subcoracoid space is recommended as subcoracoid impingement may have led to the cumulative injury to the rotator interval structures. Reconstruction of the stabilizing structures in the rotator interval, with attention paid to the superior glenohumeral ligament and the coracohumeral ligament, and the creation of a sling around the tendon can be performed. However, recurrent instability can be a problem, and a stenosed, painful tendon may result.
SLAP Lesion (Superior Labrum Anterior and Posterior)
Superior glenoid labrum injuries were apparently first defined as SLAP (superior labrum anterior and posterior) tears by Snyder et al. in 1990. While the recognized varieties of SLAP injuries have expanded over time, the challenge is to differentiate between the labral variations that are clinically relevant lesions and those that are normal variations or simply the effects of aging. SLAP lesions can be created by various mechanisms of injury including a biceps traction overload caused by the long head of the biceps acting as a decelerator of the arm during the follow-through phase of throwing, arm acceleration during the late cocking phase, a tight posterior aspect of the capsule, falling on the outstretched arm creating shearing forces on the superior biceps labral complex, sudden forced abduction and external rotation of the shoulder, and passive disruption during a motor-vehicle accident when the shoulder-lap belt restrains the ipsilateral chest wall, causing the shoulder to roll around the seat belt.
Clinically relevant SLAP lesions are most often found after trauma, in swimmers, or in long-time overhead-throwing athletes. The patients describe clicking and popping often associated with anterior shoulder pain and reduced function, including decreased throwing or serving velocity or slower swimming speed. The symptoms may appear suddenly or gradually. The dead-arm syndrome is characterized by the inability to throw at the preinjury velocity.
Any classification system should provide a logical method for evaluating the injury that can positively affect the treatment algorithm. The classification system now includes many more types than had been initially described. The SLAP lesion at the attachment of the biceps tendon to the superior aspect of the glenoid labrum is uncommon. A clinically relevant SLAP lesion is found during about 5% of all shoulder arthroscopies and may be confused with a normal anterior labral variation. Clinical examinations and imaging tests for the diagnosis of SLAP lesions are often unreliable, and the ultimate diagnostic confirmation is made with arthroscopy. Surgical treatment is focused on the reattachment of the unstable biceps-labral complex.
While the anatomy of the biceps tendon and the restraining structures within the rotator interval have been well defined, biceps function and the importance of the long head of the biceps are not clearly understood at this time. Pathological involvement of the biceps, when encountered, is usually associated with rotator cuff disease and possibly an impingement process. Functionally, some humeral head stability may be imparted through the biceps tendon. Options for the surgical treatment of pathological biceps conditions include decompression, débridement, tenotomy, and tenodesis. The most important factors to be taken into account when choosing between tenodesis and tenotomy are the activity expectations of the patient, the importance of the cosmetic result, patient compliance, associated pathological entities requiring a surgical procedure that may allow easy incorporation of a tenodesis, and the patient’s age. Those over the age of sixty appear to tolerate a tenotomy with the fewest side effects.