Purpose: The purpose of this study was to analyse results of the inverted shoulder prosthesis (Grammont Delta III prosthesis) for surgical treatment of malignant tumours of the upper portion of the humerus in twelve patients.

Material and methods: Twelve patients were treated in two centres (six patients each). There were five women and seven men, mean age 51 years (34–69). Seven had a primary tumour and five had a unique secondary tumour. All tumours were implanted after Malawer I resection (IA four case and IB two cases), with an autologous bone graft using resected irradiated bone. All resections were wide as needed for healthy margins. Resection extended to the lower fourth of the humerus in four cases, to between the lower fourth and third in six cases and to the upper third or less in two cases. Ten patients were reviewed at a mean follow-up of 22 months (7–60) to assess clinical function (Constant score) and radiographic results. Two patients with a unique secondary tumour died within the six months following surgery due to progression of the primary tumour.

Results: The mean Constant score was 58.75 (30–81.1). Weighted for age and gender, the result was 70.3% (32.6–82). Five sedentary patients were able to resume their former activities (1/2). Radiographically, there were two resorptions of the autograft, two glenoid lucent lines that did not progress, four notches in the column, and three Sneppen 1 calcifications. Mechanically, there were no prosthesis dislocations in patients whose resection extended to the lower fourth of the humerus, four dislocations in the one-fourth one-third group (2/6) and two dislocation in the upper group (2/2).

Discussion, conclusion: Functional and radiographic outcome after anatomic prosthesis implantation for surgical treatment of malignant tumours of the upper portion of the humerus was directly related to the status of the rotator cuff. The Grammont Delta III inverted prosthesis provided satisfactory functional and radiographic results in this indication after Malawer I resection, irrespective of the rotator cuff sacrifice. The risk of prosthesis instability appeared to be related to the extent of the humeral resection required for cancerological cure. For patients who undergo resection of one third or more of the humerus, muscle plasty should be associated.