Capsular tear in line with the inferior glenohumeral ligament: a cause of anterior glenohumeral instability in 2 patients.

Anterior glenohumeral instability typically involves lesions associated with the inferior glenohumeral ligament complex. Multiple lesions have been described in this setting, including Bankart, humeral avulsion of the inferior glenohumeral ligament complex, and mid-substance capsular tears. These lesions are indicative of the high-force traumatic nature of anterior shoulder dislocation. Two cases of recurrent anterior shoulder instability are presented with a capsular tear perpendicular to the usual orientation and not consistent to the amount of force involved in a dislocation. Arthroscopy revealed a capsular defect from the glenoid to the humeral head in the anterior inferior glenohumeral ligamentous complex in both. This lesion is an unusual circumstance, providing another pathology to include in the differential diagnosis of anterior glenohumeral instability.