A Mechanistic Classification for Superior Labral Injuries Guides Operative Management

The purpose of this article is to provide a clinically oriented classification system for superior labral injuries based on etiology, pathoanatomy, and associated biceps-labrum anchor complex injuries. The proposed classification system is based primarily on the mechanism of superior labral injuries as an ABCD classification (A, acute trauma; B, Bankart extension from instability; C, chronic repetitive overhead activity; and D, degenerative). The recognition of the cause is paramount to appropriately treating these patients, especially when considering operative treatment. Traumatic injuries include compressive loads, axial traction, or torsional loading and can also be secondary to shoulder instability events. Chronic overuse-related superior labral injuries typically occur with repetitive overhead activities, most commonly throwing mechanisms in athletes. Degenerative changes to the superior labrum are related to normal aging processes and are often identified during evaluation and management of other conditions (e.g., rotator cuff tears). Superior labral anatomic variants may also be present that may alter labral loading. Nonoperative management is often an appropriate and effective initial treatment for superior labral injuries, unless there are obvious pathologic changes altering the mechanics of the glenohumeral joint (large labral flap tears, bucket handle tears, etc.) or other associated injuries (traumatic rotator cuff tears, fractures, etc.). Surgical treatment principles include (1) preserving normal mobility of the superior labrum/biceps tendon complex; (2) when detached, repairing the normally fixed inferior labrum anteriorly and posteriorly; (3) considering biceps tenotomy or tenodesis when pathologic changes extend into the long head of the biceps tendon; and (4) considering individual patient factors in each case. In addition to these general principles, the classification guides operative treatment. LEVEL OF EVIDENCE: Level V, expert opinion.