Posttraumatic changes of the proximal humerus: Malunion, nonunion, and osteonecrosis. Treatment with modular hemiarthroplasty or total shoulder arthroplasty.

Since 1986, 20 shoulder orthroplasties have been performed for chronic, posttroumatic changes of the proximal humerus with a modular prosthetic system. The average patient follow-up was 33 months, range 24 to 47 months. Sixteen women and four men with an average age of 69.6 years were studied. The procedure was carried out for malunion of the tuberosities or humeral head in eight patients, nonunion of the humeral head in six patients, osteonecrosis in three patients, and chronic impression fractures associated with dislocations of the humeral head in three patients. Fair, good, or excellent results were achieved in 90% of patients. The average postoperative motions were forward elevation, 111°; external rotation, 30°; and internal rotation to L2. Two failures occurred. One patient had nonunion of a tuberosity repair with superior instability and secondary impingement requiring revision surgery. A second patient had a postoperative neuropothy and posterior subluxotion with poor function. Patients younger than 70 years of age and those who did not require tuberosity osteotomy had better results. The success of orthroplasty in these difficult occurrences is dependent upon appropriate patient selection, extensive preoperative evaluation, strict attention to surgical detail, and postoperative rehabilitation. Avoidance of tuberosity osteotomy, when feasible, is advised. A modular design has advantages because it facilitates soft-tissue tensioning and tuberosity repair.