Risk of Cutibacterium acnes in Patients Undergoing Arthroscopic Rotator Cuff Repair Secondary to Unshaved Body Hair Within the Surgical Field

Introduction <i>Cutibacterium acnes</i> (<i>C. acnes</i>) infections in the setting of rotator cuff repair (RCR) can be devastating for a patient. Preoperative skin preparation prior to arthroscopic RCR typically consists of body hair clipping within the surgical field prior to prepping. We hypothesize that preoperative hair clipping will significantly reduce <i>C. acnes</i> colonization compared with unclipped controls. Methods All patients undergoing arthroscopic RCR from 2021 to 2025 were prospectively screened at a single institution for inclusion. Inclusion criterion included patients with skin hair present within the planned surgical field. The shoulder surgical field was divided into two sections. Section A underwent standard hair clipping. Section B was not clipped. The surgical field was prepped, and then one culture swab was taken from the shoulder section. All cultures were held for 21 days. Patients were followed for nine months to assess postoperative infection rates. Results The prevalence of <i>C. acnes</i> was 3.3% in the non-hair-clipped cohort and 0.0% in the hair-clipped cohort. The difference in positive cultures (shaved - unshaved) was -3.3%, 95% CI (-8.3, 0), p=0.018 (p<0.05). Bootstrap method analysis demonstrated a statistically significant decrease in infection rate in the shaved quadrants compared with the unshaved section. No postoperative infections were found at a minimum of nine months of follow-up. Conclusion Hair clipping within the surgical field for arthroscopic RCR resulted in a statistically significant decrease in <i>C. acnes</i> found on the skin.