A retrospective study was performed to evaluate the results of proximal humeral replacement prosthesis in the oncologic setting. Following tumour resection and implantation of the prosthesis, the soft tissues around the shoulder were either sutured directly to the prosthesis (three cases) or a dacron capsuloplasty was performed (five cases). Emphasis was on assessing shoulder instability. Eight patients were availaible for the study. Three patients needed to be re-operated for instability. Average instability rating on the ASES visual analog scale was 3,2/10. We conclude the prosthetic instability can be a significant problem for these patients. The purpose of this study was to assess the results of oncologic proximal humeral prosthesis with a focus on shoulder instability. Following limb-salvage procedures of the shoulder girdle, reconstruction of the soft-tissues to obtain prosthetic stability can be a major challenge. A retrospective study of patients that underwent oncologic shoulder replacement. Results were evaluated using the SF-36 questionnaire, the MSTS 1987 and 1993 scales as well as the Standardized ASES method for assessement of shoulder function, including the visual analog scale for instability. Nine patients were still living and eight of them were able to participate in this study. Average follow-up was seventy-three months. In five cases a capsuloplasty was performed using a dacron vascular prosthesis. In the remaining cases the capsule, rotator cuff or deltoid were sutured directly to the prosthesis. Average instability rating was 3,2/10 using the visual analog scale. Three patients were reoperated for instability. Two had a failed soft tissue repair with inferior dislocation of the prosthesis and one had recurrent anterior dislocation. Average MSTS 1987 and 1993 scores were 19,9 and 18,9 respectively. SF-36 scores were significantly lower than Canadian standards in the physical functioning, role physical and mental health domains. Our data show a significant rate of instability related problems following prosthetic replacement of the proximal humerus in cases of limb salvage. We were unable to indentify specific strategies to prevent this. Further research is needed to determine optimal soft tissue reconstruction for oncologic procedure about the shoulder.
