HUMERAL AVULSION OF GLENOHUMERAL LIGAMENTS AS A CAUSE OF ANTERIOR SHOULDER INSTABILITY

The avulsion of the glenohumeral ligament labral complex at the glenoi d (Bankart lesion), as well as ligamentous laxity are well known cause s of anterior shoulder instability. A lesser known entity, the humeral avulsion of glenohumeral ligaments (HAGL), was studied to determine i ts incidence and its role in anterior glenohumeral instability. Sixty- four shoulders with the diagnosis of anterior instability were prospec tively evaluated by arthroscopy for intraarticular pathology, includin g Bankart, capsular laxity, and HAGL lesions. Six shoulders were found to have HAGL lesions (9.3%), 11 shoulders with generalized capsular l axity (17.2%), and 47 shoulders with Bankart lesions (73.5%). In patie nts with documented anterior instability without a demonstratable ''pr imary'' Bankart lesion, a HAGL lesion should be ruled out. This lesion is readily recognized arthroscopically, and an appropriate repair of this lesion can restore anterior stability to the patient. The patholo gical anatomy of the HAGL lesion and our treatment of this lesion is d iscussed.