The use of the reverse shoulder prosthesis for the treatment of failed hemiarthroplasty for proximal humeral fracture.

BACKGROUND

Humeral hemiarthroplasty is an established treatment for patients with selected fractures of the proximal part of the humerus. However, a subset of patients have development of glenoid arthritis and rotator cuff deficiency due to tuberosity failure. To date, there has been no reliable salvage procedure for this problem.

METHODS

Over a period of five years, twenty-nine patients (twenty-five women and four men) with a mean age of sixty-nine years (range, forty-two to eighty years) were managed with removal of a hemiarthroplasty prosthesis and revision with a Reverse Shoulder Prosthesis alone or in combination with a proximal humeral allograft. Patients were followed clinically and radiographically for an average of thirty-five months. All patients were evaluated with use of the American Shoulder and Elbow Surgeons score; the Simple Shoulder Test; range-of-motion measurements, including abduction, forward flexion, and external rotation; and a rating scale for overall satisfaction with the outcome of the surgery. Patients were assessed preoperatively and at all follow-up points beginning at three months postoperatively.

RESULTS

The average total American Shoulder and Elbow Surgeons score improved from 22.3 preoperatively to 52.1 at the time of the last follow-up (p < 0.001). The average American Shoulder and Elbow Surgeons pain score improved from 12.2 to 34.4 (p < 0.001), and the average American Shoulder and Elbow Surgeons function score improved from 10.1 to 17.7 (p = 0.058). The average Simple Shoulder Test score improved from 0.9 to 2.6 (p = 0.004). Forward flexion improved from 38.1 degrees to 72.7 degrees (p < 0.001), and abduction improved from 34.1 degrees to 70.4 degrees (p < 0.001). The overall complication rate was 28% (eight of twenty-nine). At the time of the latest follow-up, sixteen patients rated the outcome as good or excellent, seven rated it as satisfactory, and six were dissatisfied. Four of the six patients who were dissatisfied had been managed with a Reverse Shoulder Prosthesis alone.

CONCLUSIONS

The Reverse Shoulder Prosthesis offers a salvage-type solution to the problem of failed hemiarthroplasty due to glenoid arthritis and rotator cuff deficiency following tuberosity failure. The early results reported here are promising. In cases of severe proximal humeral bone deficiency, augmentation of the Reverse Shoulder Prosthesis with a proximal humeral allograft may improve patient satisfaction.