Anterior Shoulder Instability Repair and Reconstruction: An Algorithm for Patients with Bone Defects

Most cases of instability of the shoulder do not involve a significant osseous lesion. Bony lesions of the glenoid and humeral head, however, can be a major cause of recurrent anterior glenohumeral instability. Unrecognized bony glenoid defects and Hill-Sachs lesions can lead to failure after arthroscopic soft tissue stabilization procedures for anterior instability. However bony defects can usually be identified and effectively treated, if an appropriate protocol and workup is followed. Current indications for the treatment of anterior glenohumeral instability with a bony augmentation procedure include anteroinferior glenoid bone loss of greater than 20%-30%, an engaging Hill-Sachs lesion, or an Instability Severity Index Score greater than 6. A variety of procedures have been described for treating bony instability, including both arthroscopic and open techniques. Here we discuss the evaluation, workup, and treatment of anterior shoulder instability related to bone deficiency of the glenohumeral joint.