Use of a Functional Antibiotic Spacer in Treating Infected Shoulder Arthroplasty

Management of an infected shoulder arthroplasty remains challenging. Treatment goals include resolution of the infection, improvement in pain, and restoration of function. Two-stage revision with an antibiotic spacer and subsequent revision has shown variable success in achieving these goals. The practice of using a hemiarthroplasty and coating the stem with antibiotic cement without cementing the implant to the humerus (functional antibiotic spacer) during the first stage has the potential to achieve treatment goals without the need for a second revision. The goal of this study was to examine the outcomes of a maintained functional antibiotic spacer without a second revision for the management of infected shoulder arthroplasty. Fourteen patients with an infected shoulder arthroplasty underwent implantation of a functional antibiotic spacer, extensive surgical debridement, and a minimum of 6 weeks of treatment with postoperative intravenous antibiotics. The 9 patients who elected not to undergo revision surgery were included in this analysis. Pain scores, functional outcome scores, range of motion, strength, and patient satisfaction were measured for these patients at last follow-up and compared with preoperative scores. At an average follow-up of 25 months (range, 12-48 months), significant improvements were observed in functional outcome scores, shoulder abduction, and elevation, with a trend toward improvement in pain scores. One patient was unsatisfied with the result. No recurrent infection, progressive radiolucency, or change in position of the functional antibiotic spacer was observed. A functional antibiotic spacer effectively manages the infected shoulder arthroplasty while achieving significant improvements in function and motion. Patient satisfaction was high, with a relatively low rate of conversion to second-stage revision.