Detection of Cutibacterium acnes in arthroscopic rotator cuff and bankart repair

Background: We evaluated the detection rate for Cutibacterium acnes (C. acnes) in patients who underwent arthroscopic cuff repair and Bankart repair. Methods: Arthroscopic cuff repair was performed in 105 patients (R group) and arthroscopic Bankart repair was performed in 29 patients (B group). Skin swabs prior to antisepsis, intraoperative synovial swabs of the glenohumeral joint (immediately after incision and prior to wound closure), suture of suture anchor, and postoperative swabs from the tip of arthroscope were cultured. Evaluation criteria were compared between groups and included the presence or absence of diabetes mellitus, operation time, frequency of preoperative injections, deep infections, and detection rate of C. acnes in multiple regions of the body. Results: There were 14 patients (12.2%) in the R group and one patient in the B group (3.6%) with diabetes mellitus, and no significant difference was found between the two groups. The frequency of injections to the shoulder was significantly greater in the R group at 3.6 +/- 4.2 times compared to the B group at 1.6 +/- 2.0 times. There were no deep infections in either groups. The detection rate for C. acnes was significantly greater in the synovial swabs alone (skin swabs for R and B groups, 42.3% and 47.6%, respectively; synovial swabs, 10.4% and 1.8%; suture, 8.7% and 0%; tip of arthroscope, 4.3% and 0%). Conclusions: A significantly greater number of C. acnes samples were detected from synovial swabs of cuff tears, suggesting that its presence may be due to preoperative injections to the shoulder. (C) 2019 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.