Comparative efficacy of vancomycin and gentamicin soaked hamstring autografts in reducing infection rates following ACL reconstruction

Background: Deep knee infection after anterior cruciate ligament reconstruction (ACLR) is uncommon but carries a disproportionate clinical burden, often ending in graft loss and staged revision surgery. Because systemic antibiotics penetrate avascular tendon poorly, presoaking the harvested graft in a topical antibiotic solution has emerged as a practical adjunct to standard intravenous prophylaxis. Vancomycin has the largest published experience for this purpose, while gentamicin has been proposed as a comparably effective and more practical alternative. Objective was to directly compare vancomycin-soaked and gentamicin-soaked hamstring autografts for their effect on postoperative infection rate and functional recovery following arthroscopic ACLR. Methods: Eighty patients undergoing primary ACLR over a six-month period were divided into two groups of 40: group 1 received autografts presoaked in vancomycin (500 mg/vial), and group 2 received autografts presoaked in gentamicin (40 mg/2 ml). Both groups received identical intravenous antibiotic prophylaxis, surgical technique, and rehabilitation. Functional recovery was assessed with the IKDC subjective knee score preoperatively and at three and six months. Results: The cohort comprised 52 men and 28 women, with injuries distributed almost evenly between the right (36) and left (44) knee. Non-contact mechanisms accounted for the largest share of injuries (45), followed by road traffic accidents (20) and sport (15). One deep knee infection occurred in the entire cohort, in a patient from the gentamicin group (group 2), giving group-wise infection rates of 0% (group 1) and 2.5% (group 2). The combined IKDC score rose from a mean of 34±3.1 preoperatively to 54±2.6 at three months and 93.5±1.5 at six months. Conclusions: Both vancomycin and gentamicin graft-presoaking were associated with a low overall infection rate and comparable functional recovery, supporting either agent as a reasonable, low-cost adjunct to intravenous prophylaxis during ACLR. Larger comparative trials are needed to establish whether either antibiotic carries a true advantage over the other.