Posterior shoulder instability.

Understanding the anatomic restraints to posterior shoulder instability and the resulting pathophysiology helps the treating physician make a correct diagnosis and formulate an appropriate treatment plan. A nonoperative program directed at reducing pain and increasing stability through comprehensive shoulder strengthening methods has generally been successful in treating recurrent posterior shoulder subluxation. Surgical options for treatment are reserved for those patients who fail to recognize improvement after six months of therapy and have no evidence of a psychological disturbance as the cause of their posterior instability.