Recurrent posterior instability (subluxation) of the shoulder.

A retrospective survey of fifty shoulders in thirty-five patients with recurrent posterior instability revealed generally poor results of treatment, particularly of operative treatment. Only eleven of the shoulders had a primary traumatic insult as the event initiating the instability. Although forty-one of the affected shoulders demonstrated voluntary instability, it was the associated involuntary, unintentional instability of these shoulders that prompted the patients to seek medical attention. Pain and functional impairment relating to work and to the activities of daily living were not significant in most of these patients. The results of surgical reconstruction were generally poor, the recurrence rate was 50 per cent (thirteen of twenty-six shoulders), and there were complications in five of the twenty-six shoulders that had been operated on. Attention is drawn to the complication of degenerative osteoarthritis that is associated with posterior glenoid osteotomy. We advise care in the selection of patients for surgical reconstruction.