Functional outcome of reverse shoulder tumor prosthesis in the treatment of proximal humerus tumors

Abstract

Background: The treatment of proximal humerus tumors with reverse shoulder arthroplasty with allograft augmentation is still controversial. A tumor prosthesis represents a proven solution for such osseous defects. We investigated the functional results of patients who underwent reverse shoulder tumor prosthesis (RSTP) without the use of allograft after resection of a proximal humerus tumor.

Methods: We retrospectively evaluated 10 patients with malignant proximal humerus tumors who had undergone RSTP, with a mean follow-up period of 18.2 months (range, 6-27 months). The average age of the patients was 49.4 years. The mean resection length was 10.2 cm (range, 6-16 cm). The tumor prosthesis was preferred for the humeral component. Released rotator cuff muscles were reattached to the prosthesis with nonabsorbable sutures.

Results: The mean active forward flexion was 96° (range, 30°-160°), the mean active abduction was 88° (range, 30°-160°), and the mean active external rotation was 13° (range, 0°-20°). The mean Constant-Murley score was 53.7%. The mean Disabilities of the Arm, Shoulder, and Hand score was 26.2. The mean visual analog scale score was 1.3. The mean Musculoskeletal Tumor Society score was 78.1%. None of our patients have shown local recurrence or infection signs in the follow-up period.

Conclusions: Functionally satisfying results and a stable shoulder can be achieved by reverse shoulder arthroplasty without the need for an allograft. An intact abductor mechanism with a shorter resection humerus length produced good results. The treatment of malignant proximal humerus tumors with RSTP is an alternative that minimizes surgery time and complexity.

Keywords: Malawer classification; Reverse shoulder; arthroplasty; proximal humerus tumors; tumor prosthesis.