Neer Award 2018: Benzoyl peroxide effectively decreases preoperative Cutibacterium acnes shoulder burden: a prospective randomized controlled trial

Background Benzoyl peroxide (BPO) solutions effectively reduce Cutibacterium acnes (formerly Propionibacterium acnes ) on the face, neck, and back in nonoperative settings. This study compared preoperative application of BPO vs. chlorhexidine gluconate (CHG) in decreasing shoulder C acnes skin burden in surgical patients. Methods Eighty patients undergoing shoulder surgery were prospectively enrolled in a randomized double-blind trial at 1 institution from August 2015 to April 2017. Participants were randomized to 5% BPO or 4% CHG for 3 consecutive days. The nonoperative shoulder had no intervention and served as the negative control. Skin cultures of both shoulders were obtained via a detergent scrub technique the day of surgery at anterior, lateral, and posterior sites and the axilla. Results Fewer positive cultures were obtained from the BPO-treated side compared with the contralateral side ( P  = .0003), and no change was shown for the CHG group ( P  = .80). Shoulders treated with BPO showed a statistically significant reduction in C acnes counts compared with CHG at anterior ( P  = .03) and posterior ( P  = .005) portal sites. No significant difference was found at the axilla ( P  = .99) or lateral portal site ( P  = .08). No postoperative infections or wound complications occurred in either group. Conclusions BPO is more effective than CHG at reducing C acnes on the shoulder. Decreasing the skin burden of C acnes may reduce intraoperative wound contamination and postoperative infection. BPO should be considered as an adjunctive preoperative skin preparation considering its potential benefit, low risk, and low cost.