Evaluation of sterilization methods following contamination of hamstring autograft during anterior cruciate ligament reconstruction

Purpose Inadvertent contamination of the hamstring autograft during ACL reconstruction is infrequent, but can result in significant complications. The purpose of this study is to evaluate bacterial contamination of hamstring autografts dropped onto the operating room floor and methods of graft decontamination. Methods Hamstring tendons were harvested from patients. Excess tendon not used in the ACL procedure was divided into 6 segments. Segments were assigned to 6 groups (A through F, N = 30 in each group): group A: uncontaminated graft immediately postharvest (control), group B: graft dropped onto the floor (5 s), group C: graft dropped onto the floor (15 s). grafts in groups D to F were dropped onto floor for 15 s then rinsed with saline (group D), bacitracin solution (group E) or chlorhexidine 4 % solution (group F) for 3 min. All grafts were sent to the microbiology laboratory for anaerobic and aerobic cultures. Results Cultures were positive in 23 % of graft segments from group A (7/30), 33 % of grafts from group B (10/30), 23 % from group C (7/30), 30 % from group D (9/30) and 3 % from both group E (1/30) and group F (1/30). Sixteen unique organisms were identified, with Staphylococcus aureus as the most common isolate. Grafts rinsed in either bacitracin solution or 4 % chlorhexidine solutions were significantly less likely to be culture positive when compared to control graft segments ( p