Posterior dislocation of the humeral head in association with obstetric paralysis.

Twelve children with obstetric paralysis were diagnosed as having a posterior dislocation of the humeral head. The diagnosis was suspected on clinical grounds and confirmed by computed tomography (CT) scans in all cases. All 12 patients were treated with open reduction via an anterior approach. The age range at the time of surgery was from 7 months to 7 years (average, 2 years and 3 months). All patients were immobilized in a shoulder spica for 6 weeks and a further 6 weeks in an orthosis. All patients were examined by CT scans in the postoperative period, which confirmed a satisfactory reduction in all cases. With a minimal follow-up of 12 months, there have been no redislocations. This article demonstrates that dislocation of the shoulder in association with obstetric paralysis is not rare, as previously described, and shows that once diagnosed, the dislocation can be satisfactorily treated by a single anterior open reduction of the shoulder.