The pathology of shoulder instability includes injury to both labrum and capsule. Labral injury can occur via separation of the labrum from the glenoid rim or direct bony injury to the anteroinferior glenoid. In most cases, capsular injury occurs as plastic deformation of the capsule or capsule stretching. However, in a small number of cases, capsular rupture either midsubstance or directly off the humeral attachment may occur.

Full Article: Humeral Avulsion of the Glenohumeral Ligament: Injury Pattern and Arthroscopic Repair Techniques