Does the retention of osseointegrated prosthetic implants during the surgical management of chronic infections following reverse total shoulder arthroplasty (RTSA) influence functional outcomes without impacting the efficacy of the infection treatment?

Abstract

Introduction: The gold standard (GS) for treating chronic infections following reverse total shoulder arthroplasty (RTSA) is a complete exchange of the prosthesis carried out in one or two stages. This surgical procedure, which may damage the bone stock, can result in poor functional outcomes due to intraoperative complications. The purpose of this study was to compare the GS to a surgical technique that retained osseointegrated implants: the partial one-stage exchange.

Hypothesis: Partial one-stage exchange was effective in treating chronic infections after RTSA (no recurrent infection) and resulted in better functional outcomes than the GS.

Materials and methods: This retrospective single-center study included 18 patients with chronic infection after a primary RTSA. Two treatments were compared in a non-randomized fashion. The first included 11 patients who underwent a partial one-stage exchange with implant retention in case of macroscopic osseointegration. The second included seven patients who were treated with the GS: six patients with a complete one-stage exchange and one patient with a two-stage surgical approach. The absence of recurrent infection and functional outcomes were assessed after a minimum of two years.

Results: There were no statistically significant differences in treatment efficacy between the two strategies: 91% vs. 100%, respectively. The partial one-stage exchange resulted in a significantly improved shoulder function compared to the GS with postoperative Constant scores of 55±14.58 vs. 44±14.45, respectively (p=.03). In the partial one-stage exchange group, there was a significantly improved shoulder function with a preoperative Constant score of 40 [28-55]±9.04 preoperatively vs. 55 [25-75]±14.58 postoperatively (p=.01). The GS treatment did not significantly improve the postoperative function (p=.09).

Discussion: Partial one-stage exchange does not compromise treatment efficacy of chronic infections after RTSA. This technique resulted in better shoulder function than a conventional GS-type management. A study with greater statistical power is required.

Level of evidence: III; clinical series, retrospective, single-center.

Keywords: Complication; Infection; Prosthesis; Revision; Shoulder.