Classification of anterosuperior glenoid labrum variants and their association with shoulder pathology.

Unlabelled: This prospective study of 367 consecutive shoulder arthroscopies assessed variants of the anterosuperior glenoid labrum and associated shoulder pathology. Thirty-three shoulders were excluded because of prior surgery, septic arthritis, or adhesive capsulitis. Anterosuperior glenoid variants were classified as: type I, cordlike middle glenohumeral ligament without sublabral foramen; type II, sublabral foramen without a cordlike middle glenohumeral ligament; type III, sublabral foramen with a cordlike middle glenohumeral ligament; and type IV, absent anterosuperior labrum with the anterior aspect of the superior labrum continuous with a cordlike middle glenohumeral ligament. The presence of these variants was correlated with the incidence of shoulder pathology found on arthroscopic inspection. Of 334 shoulders, 118 (35.3%) had variants of the anterosuperior glenoid labrum. Of these, 32 (27.1%) were type I, 27 (22.9%) were type II, 34 (28.8%) were type III, and 25 (21.2%) were type IV. The incidence of advanced superior labrum anterior-posterior lesions in the 86 shoulders displaying a type II, III, or IV variant was significantly higher than in shoulders with no anterosuperior variant (48.8% versus 23.6%, P<.001). Other pathologic findings were not significantly increased in shoulders with variants compared to those without.

Level Of Evidence: Level 1.