Amin H Afsari
The term anterior glenohumeral instability refers to a shoulder in which soft-tissue or bony insult allows the humeral head to sublux or dislocate from the glenoid fossa. The function of such a shoulder is compromised. Patients typically experience apprehension, recurrent subluxations, and frank dislocations. This pathology limits many activities, including overhead arm motions, external rotation, and, thus, physical or athletic activities.
The shoulder is the most commonly dislocated joint in the body. When shoulder dislocation occurs in adolescents and children, it has the worst natural history of any injury; the rate of recurrence in later years is at least 70%.
As many as 95% of shoulder dislocations are anterior. Anterior dislocations often lead to recurrent anterior glenohumeral instability. Recurrent anterior glenohumeral instability accounts for the largest portion of the shoulder laxity spectrum. Excessive deviation of the humeral head on the glenoid occurs in all or one of three directions: anterior, posterior, or inferior. Although certainly not life-threatening, recurrent subluxation or dislocation is clearly lifestyle-threatening and can effectively disable an otherwise active individual.