Effectiveness of gentamicin-containing collagen sponges for prevention of surgical site infection after hip arthroplasty: a multicenter randomized trial.

BACKGROUND Surgical site infection (SSI) is a feared complication in hip arthroplasty, especially following femoral neck fracture in the elderly, associated with substantially increased morbidity, mortality, and costs. Gentamicin-containing collagen sponges are widely used for prevention of SSIs, but their effectiveness in joint replacement surgery remains unclear. METHODS We performed a multicenter, randomized trial between February 2011 and July 2013. Eligible patients with femoral neck fracture undergoing hemiarthroplasty were randomly assigned to receive either intravenous antimicrobial prophylaxis alone or with the addition of 2 gentamicin-containing collagen sponges into the hip joint perioperatively. The primary end point was SSI according to the Centers for Disease Control and Prevention criteria within 30 days after surgery. RESULTS Seven hundred thirty-nine patients were randomly assigned, 684 of whom were included in the modified intention-to-treat analysis. There was no statistical significant difference in SSI between the gentamicin-collagen group (16 of 329 patients [4.9%]) and the control group (19 of 355 patients [5.4%]) (relative risk [RR], 0.91 [95% confidence interval, .48-1.79]; P = .77). No significant differences were observed between the groups in superficial SSI (2 of 329 [0.6%] vs 3 of 355 [0.8%]; P = .99) and deep SSI (14 of 329 [4.3%] vs 16 of 355 [4.5%]; P = .87). There were no significant differences between the groups regarding type of bacteria isolated. CONCLUSIONS Locally administered gentamicin-collagen sponges did not reduce the incidence of SSI in elderly patients treated with a hemiarthroplasty because of femoral neck fracture. CLINICAL TRIALS REGISTRATION NCT01287780.