Abstract
Acute traumatic posterior shoulder instability is a rare injury. Such injuries can result in significant bone defects of the anterior humeral head that require surgical intervention. In the past, small to medium defects have been treated by a soft-tissue or bone transfer into the lesion. We present an arthroscopic technique for addressing these lesions in which the middle glenohumeral ligament is sutured into the defect, thereby making it an extra-articular defect and preventing it from engaging the posterior glenoid.