Evaluation of Neer's hemi-arthroplasty in the treatment of humeral fractures

Eighteen patients with fractures of the proximal humerus with at least four fragments, with or without dislocation (group IV, V and VI of Neer's classification), were treated by hemiprosthetic replacement. The average age was 59 years. The follow-up was from 1 to 7 years. Patients were assessed on two occasions by two evaluators using Neer's protocol. The glenohumeral and the scapulothoracic movements, using the other shoulder as control, were measured radiologically at 0 degrees, 45 degrees and maximal abduction. Pain, function and range of motion were recorded. No complication was encountered. By radiologic assessment, it was possible to classify results in three groups. In all of the unsatisfactory results, the centre of motion of the prosthesis was displaced proximally. Satisfactory and excellent results were obtained in 66%. The best results are obtained if patients are operated on early; repair of the rotator cuff is important. The centre of rotation of the prosthesis must be in precise biomechanical relation to the glenoid fossa; such a relation is of prognostic value.