The Efficacy and Safety of Prophylactic Treatment Methods for Cutibacterium Acnes Infection in the Shoulder: A Systematic Review of Level of Evidence I Randomized Controlled Trials.

Background: Cutibacterium acnes (C. acnes), formerly Propionibacterium acnes (P. acnes), is the most common pathogen responsible for postoperative shoulder infections. Prevention of shoulder infection is crucial to improving patient outcomes, prolonging implant longevity, and reducing costs. The purpose of this study is to evaluate the effectiveness of various prophylactic treatments for C. acnes in the shoulder.

Methods: A systematic review of 15 randomized controlled trials was conducted to evaluate the effectiveness of various skin preparation methods in the reduction of C. acnes for patients undergoing shoulder surgery. Three electronic databases were queried as follows: PubMed, Embase, and the Cochrane Library databases. Data extraction for this study was performed by three independent reviewers, and only level I studies were included. Outcomes were assessed based on the effectiveness of the method used; side effects were also analyzed.

Results: Fifteen studies were included in this review. Seven studies utilized a regimen of at-home treatment in the days leading up to culture sampling, while the other eight studies administered treatment just prior to sampling. Seven studies found their respective treatment methods to be statistically significant. No preparation methods applied immediately prior to sampling showed conclusive superiority. The application benzoyl peroxide in the days prior to sampling showed significantly lower rates of colonization when compared to control groups in five separate studies.

Conclusion: There remains no consensus on the optimal skin preparation method immediately prior to surgery, however, acne cream applied in the days leading up to surgery has been shown to significantly reduce the bacterial load of C. acnes. While BPO appears to be the superior method of prophylactic treatment, it is also associated with higher rates of complications and skin reactions following treatment; thus, caution is warranted. Further studies should investigate whether this reduction in bacterial load translates to meaningfully lower rates of periprosthetic joint infections.