[Results of an inverted shoulder prosthesis after resection for tumor of the proximal humerus].
OBJECTIVE
Treatment of primary bone tumors of the proximal humerus is a major challenge, both in terms of oncological cure and limitation of functional handicap. Extracorporal radiation and reimplantation have provided satisfactory results for the treatment of bone tumors and the inverted shoulder prosthesis has be found to be effective in treating rotator cuff deficiency. We therefore assessed patients treated with a combination of these two treatments in order to search for a better functional outcome.


METHODS
Conservative resection of the tumor with reconstruction using an inverted shoulder prosthesis was performed in six patients with a tumor of the proximal humerus of type Ia or Ib in the Malawer classification or type S3-S4-S5 in the Musculoskeletal Tumor Society classification. Patients whose tumor involved the deltoid or the glenohumeral joint were not considered for this procedure. The series included four men and two women (4 left and 2 right shoulders) aged 51 years on the average at the time of surgery.


RESULTS
Mean follow-up was 12 months. The mean age- and sex-adjusted Constant score was 74% (70-85%). The patients were generally satisfied and were able to continue their daily activities. There were two displacements, one of which was diagnosed immediately and reduced without anesthesia. An abduction pad was worn for six months after reduction. The post-operative period was uneventful. No local recurrence has been observed.


CONCLUSIONS
Our results compared favorably with other therapeutic options for resection-reconstruction reported in the literature: functional outcome was better and more predictable, at least in the short term; oncological results were satisfactory although the follow-up is short, particularly for the three primary malignant tumors. It is known however that the long-term oncology result depends on the quality of the resection and the efficacy of the extracorporeal radiation. Shoulder motion outcome was the least satisfactory in patients who experienced peri-operative complications. We were unable to find any relation between less satisfactory functional outcome and the number of surgical procedures for local recurrence before extracorporeal radiation and arthroplasty (deltoid dystrophy). Normal deltoid function appeared to be crucial for optimal functional outcome with this prosthesis which allows sacrifice of the rotators. The rate of complications was low and recovery of active shoulder movement was more rapid. Despite the short-term nature of these results, and despite the risk of loosening, the inverted shoulder prosthesis appears to be an interesting therapeutic option for these patients.
Département de Chirurgie Orthopédique, Hôpital Universitaire, De Pintelaan 185, 9000 Gand, Belgique.
L F
LF
De Wilde
E
E
Van Ovost
D
D
Uyttendaele
R
R
Verdonk
D000203:Activities of Daily Living; D019643:Arthroplasty, Replacement / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods*; D001859:Bone Neoplasms / Q000145:classification / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006811:Humerus; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011474:Prosthesis Design; D016059:Range of Motion, Articular; D012399:Rotation; D012785:Shoulder Joint; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome