Immobilization after primary dislocation of the shoulder.

A total of 226 patients with primary shoulder dislocation were followed up for 1 year, the primary object being to observe the effect of immobilization on the incidence of redislocation. The shoulders were immobilized in a mitella for 1 week in all the 127 patients older than 50 years of age, and in 53 of the patients under 50 years of age. The shoulders of the remaining 46 patients (under 50 years) were completely immobilized with a stockinette-Gilchrist bandage for a period of 3 weeks. Thirteen per cent (30/226) suffered from one to four redislocations each during the follow-up period. Because most recurrences occurred in the patients under 30 years of age, these patients were compared with the older ones in the analysis. The frequency of redislocation was higher in the group of 53 patients under 30 years than in the older subgroup (P less than 0.001). Twenty-six of these 53 patients (under 30 years), who had been immobilized for 1 week, presented a higher frequency of redislocation than the remaining 27 patients subjected to 3 weeks' immobilization (P less than 0.05). Manual labourers experienced more numerous redislocations than office workers (P less than 0.01). The greater the initial trauma to the shoulder, the lower was the incidence of recurrence. There were only two among the 57 patients with early complications of the primary shoulder dislocation who had a redislocation (P less than 0.001). Residual stiffness was encountered more often in the patients over 30 years than in the younger ones (P less than 0.001). Following primary shoulder dislocation, 1 week's immobilization in a sling is sufficient in patients over 30 years, while in the case of most of the younger patients 3 weeks' complete immobilization of the shoulder is recommended.