Incidence of Cutibacterium acnes in arthroscopic Bankart repair for traumatic anterior shoulder instability

Background: We evaluated the detection rate of Cutibacterium acnes (C. acnes) for patients who underwent arthroscopic Bankart repair for traumatic anterior shoulder instability. Methods: Study subjects included 36 patients who underwent arthroscopic Bankart repair. Skin swabs prior to antisepsis, intraoperative synovial swabs of the glenohumeral joint (immediately after incision and prior to wound closure), and the suture of the suture anchor were cultured. Evaluation criteria included the detection rate of C. acnes in multiple regions of the body. Results: Using a skin swab culture test, C. acnes was detected in 63 of 108 samples (58.3%). The bacterium was detected in 2 of 36 samples (5.5%) and 4 of 36 (11.1%) in the synovial swab culture of the glenohumeral joint immediately after surgical incision and immediately before wound closure, respectively. In the suture culture of the suture used in the arthroscopic Bankart repair, C. acnes was detected in 1 of 36 samples (2.8%). Conclusions: C. acnes was detected in patients undergoing surgeries for shoulder instability. The relationship between C. acnes and the pathological condition of shoulder instability remains unknown.