indow.status=this.title; return true;” onmouseout=”window.status=”; return true;”>2,
rotation (9). An otherwise normal finding may increase with repetitive stresses, potentially leading to a painful condition.
Stay updated, free articles. Join our Telegram channel
Full access? Get Clinical Tree
Shoulder Superior Labrum Anterior and Posterior Tears and Biceps Tears
INTRODUCTION
Superior labrum anterior to posterior (SLAP) tears can be a cause of shoulder pain following repetitive extension or traction injuries.
The increased number of postoperative complications following surgical repair have raised questions about patient selection and treatment.
Successful return to preinjury throwing activities has not been as successful as was once thought.
SUPERIOR LABRUM
SLAP tears may be an isolated etiology for shoulder pain or in combination with other pathology.
The superior labrum is the part of the cartilaginous ring that extends anterior and posterior to the biceps insertion. The labrum contributes to depth of the shallow glenoid, increasing humeral head contact and stability. Capsular ligaments and the long head of the biceps attach to the labrum and to the adjacent glenoid. Disruption of the labrum affects the attached ligaments and long head of the biceps (28).
Superior labral tears have been described, as shoulder arthroscopy experience has increased (41). Arthrotomy with division of the subscapularis did not allow visualization of this anatomy, and little has been mentioned in the literature prior to 1985 (5).
Anatomic variants and developmental changes with age can initiate tissue failure (14). The greatest success with surgical treatment is following traumatic instability events.
Overhead sports, as in baseball pitching, may place additional stresses on the superior labrum. As sports participation and injury recognition increase, so does the experience in treatment of injuries to the superior labrum (<A onclick="if (window.scroll_to_id) { scroll_to_id(event,'R2-50'); return false; }" onmouseover="wdjacent articular cartilage should demonstrate abnormal wear, suggesting instability of the superior labrum in pathologic settings (37).
Superior labral tears (SLAP e; }” xpath=”/CT{06b9ee1beed59419fa2bedb37ace85f4ef50397bb3c2ea48f132154d6696ac7aeea5de6283b4d47540001e1febd10d22}/ID(R8-50)” title=”8″ onmouseover=”window.status=this.title; return true;” onmouseout=”window.status=”; return true;”>8,16).
Superior Labrum Anatomy
The labrum is a cartilaginous ring surrounding the perimeter of a shallow glenoid, contributing to depth and humeral head contact (23). Superior labrum lesions can occur alone or can extend to create anterior or posterior labral avulsions.
The superior labrum consists of dense fibrocartilage and elastin that connects the superior and middle capsular ligaments and long head of the biceps to the glenoid.
Normal variants include a fovea, a Buford complex, and a peel-back labrum. The fovea is an incomplete anterior superior labral attachment to the glenoid with a hole or thin fibrous tissue between the labrum and the glenoid (11). A Buford complex is a thickened middle glenohumeral ligament band that inserts at the biceps labral junction with an absent anterior superior labrum (44). A large fovea or superior labral absence may mistakenly resemble an avulsion injury. The posterior superior labrum may be attached to the glenoid neck rather than to the articular margin (9). Variations of labral attachment can be normal embryonic variants or repetitive activity adaptations.
Arthroscopic evaluation along the undersurface of the labrum and aaeea5de6283b4d47540001e1febd10d22}/ID(R37-50)” title=”39″ onmouseover=”window.status=this.title; return true;” onmouseout=”window.status=”; return true;”>39). In addition, arthroscopists have noted SLAP tears associated with some patients with posterior and multidirectional shoulder instability (1).
The rotator cuff interval plays a role in stabilizing the adducted shoulder (40). Expanded classification includes extension of Bankart lesions (20,38).
Superior labral tears can allow extraarticular collection of synovial fluids encapsulating as paralabral cysts. These cysts, often recognized on magnetic resonance imaging (MRI) or ultrasound exam, can create pressure on adjacent structures (25).
The anatomy can be visualized arthroscopically in a static and dynamic exam. The peel-back labrum can be seen arthroscopically as loss of posterior superior, glenoid contact when the shoulder is placed in abduction and external
Superior Labrum Function
Superior labrum contributes to superior, anteroinferior, inferior, and posterior glenohumeral stability. Superior humeral head translation can be reduced with secure attachment of the superior labrum and its biceps and capsular attachments. Investigators have increased anteroinferior translation after creating superior labral tears (34,39). In addition, arthroscopists have noted SLAP tears associated with some patients with posterior and multidirectional shoulder instability (1).
The rotator cuff interval plays a role in stabilizing the adducted shoulder (22). This interval consists of the superior labrum, superior glenohumeral ligament, middle glenohumeral ligament, and coracohumeral ligament. Reduction of an enlarged interval has decreased inferior translation or sulcus, reduced anterior translation, and external rotation and can be used to augment anterior stabilization.
Superior translation of the humeral head can be limited with an intact superior labrum and biceps anchor with the humerus in external rotation (2). The long head of the biceps attaches to the superior labrum and glenoid tubercle. When the shoulder is in the cocked throwing position (abduction, external rotation, and extension), the head is translated posteriorly (24). Capsular changes and tears in the superior labrum may alter these relationships.
The superior labrum may contribute to articular lesions on the undersurface of the rotator cuff. Internal impingement is a common pathologic finding in overhead throwers with shoulder pain. Excessive contact of the posterosuperior labrum with the supraspinatus and infraspinatus during early acceleration can create partial-thickness rotator cuff tears. Subscapularis tendons can abrade on the anterosuperior labrum with flexion and internal rotation.
Superior Labral Pathologic Conditions
SLAP tears can be a source of pain and disability either in isolation or coexistent with other shoulder pathology (26,30,31). Examination of the biceps with provocative testing has been helpful in anterior tears (Speed, Yergason tests). Translation test (load and shift, jerk tests) and provocative position (relocation test) testing can produce pain but are often associated with common complaints exterior to the shoulder (i.e., the acromioclavicular joint). Some SLAP lesions are not diagnosed preoperatively, but rather at the time of arthroscopic surgery.
Imaging tests can be helpful. MRI without contrast can identify ganglion cysts adjacent to the shoulder. MRI with articular contrast may illustrate superior labral tear. Anatomic variants may contribute to abnormal imaging findings.
Superior Labral Treatment
Most common treatment for intrasubstance tears of the superior labrum is debridement (type I and III) (43). Ganglions may be asymptomatic or cause neurologic dysfunction due to peripheral pressure on the suprascapular nerve prior to the supraspinatus innervation at the scapular notch or adjacent to the scapular spine prior to the infraspinatus innervation.
Superior Labral Diagnosis
Patients most often complain of pain in provocative positions. A painful click may occasionally be reproducible, especially when associated with instability.
The mechanism of injury can be traumatic and overuse. Traumatic events include a fall on an outstretched arm, hyperextension injury, and seat belt injury. The body torso projects forward as the shoulder and arm are restrained. Overuse injuries, as in baseball pitching, accentuate internal impingement contact forces. Forced inferior translation may create superior labral avulsions due to traction on the biceps and capsular attachments.
Degenerative changes are commonly found in the superior labrum, and their significance has not been established.
Physical examination has had variable results (26