Humeral Avulsion of the Glenohumeral Ligaments (HAGL)

The shoulder is the most mobile and the most commonly dislocated large joint in the body. Dislocation means that the joint is moved out of position such that the joint surfaces on the ends of the bones are no longer in contact. In the shoulder, most dislocations are anterior (moving forward from the body). When a dislocation occurs, the soft tissues that stabilize the shoulder are can be torn. Traumatic dislocations of the shoulder can result in avulsion (pulling off) of the glenohumeral ligaments (HAGL) that attach the humerus (ball of upper arm bone) to the glenoid (socket of the shoulder joint). The ligaments can be torn or disrupted from their attachment to the humeral head (ball), so the stability of the shoulder joint is compromised and the patient is likely to experience repeat episodes of dislocation, in addition to pain and physical limitations. The concern for re-injury is greater with younger, more active patients.