Hemiarthroplasty in the treatment of comminuted intraarticular fractures of the proximal humerus.

Thirty-eight patients with four-part proximal humerus fractures and fracture dislocations were treated with humeral head replacement between 1989 and 1995. At followup (mean, 37 months; range, 12-48 months) the patients were evaluated for postoperative pain, active range of motion, muscular strength, overall function in every day activities, and patient satisfaction. Complications developed in five patients and consisted of humeral component malposition (one shoulder), rotator cuff insufficiency (two shoulders), and heterotopic ossification (two shoulders). According to the Neer criteria, the overall results were: 32 (84%) patients had no pain and improved motion (active forward elevation averaged 130 degrees, external rotation 45 degrees, and average internal rotation to the first lumbar vertebra); in this group strength and function 6 months postoperatively was 80% of the normal side and reached 90% of the normal side at 1 year postoperatively under continuous stretching and strengthening exercises; and 34 patients (90%) were satisfied with their treatment. The results of the study indicate that humeral head replacement is a dependable method to restore comfort and function to patients with acute or old four-part fractures of the proximal humerus. However, recovery of function and range of motion are much less predictable in patients with an old injury.