Can the Need for Future Surgery for Acute Traumatic Anterior Shoulder Dislocation Be Predicted?

BACKGROUND: Some surgeons believe that they can identify patients who are at high risk for shoulder redislocation and that these patients are best served by immediate surgical stabilization. This natural history study was performed to examine the validity of this concept and to determine whether it is possible to predict the need for future surgery at the time of the index injury and examination. METHODS: One hundred and thirty-one patients were followed for an average of four years after their first shoulder dislocation. An extensive history was recorded and a thorough physical examination was performed on each patient. Final evaluation consisted of a physical examination, radiographic evaluation, and determination of three outcome measurements. RESULTS: Twenty-nine (22%) of the 131 patients requested surgery during the follow-up period. There were twenty Bankart repairs and nine rotator cuff repairs. Forty-three patients (33%) had at least one recurrent dislocation. Thirty-nine of these patients were in the group of ninety patients under the age of forty years. Thirty-seven of these thirty-nine patients either participated in contact or collision sports or used the arm at or above chest level in their occupation. Eighteen (49%) of these thirty-seven patients had surgery. Only two of the more sedentary patients had redislocation, and none had surgery. Four (10%) of the forty-one patients over the age of forty had a redislocation, but none required a Bankart repair. However, eight (20%) of the forty-one patients required a rotator cuff repair. Eighty-eight (67%) of the 131 patients never had a redislocation. Their outcome scores were high and equivalent to those of the cohort of patients who had had a successful Bankart repair of an unstable shoulder. Patients who had redislocation but chose to cope with the instability rather than have surgery had lower outcome scores. Twenty-two (51%) of the forty-three patients who had recurrent instability had only one redislocation during the entire follow-up period, whereas some patients had as many as twelve complete redislocations. CONCLUSIONS: Younger patients involved in contact or collision sports or who require overhead occupational use of the arm are more likely to have a redislocation of the shoulder than are their less active peers or older persons. However, even in the highest-risk groups, only approximately half of patients with shoulder redislocation requested surgery within the follow-up period. Early surgery based on the presumption of future dislocations, unhappiness, and disability cannot be justified.