A retrospective comparison of the incidence of bacterial infection following anterior cruciate ligament reconstruction with autograft versus allograft.

PURPOSE To compare the incidence of bacterial infection in anterior cruciate ligament (ACL) reconstruction with autograft versus allograft. METHODS We completed a retrospective medical record review of ACL reconstructions performed at our institutions between 2001 and 2005. These included 170 autograft, 628 allograft, and 3 combined autograft/allograft reconstructions. Data collection included patient demographics, comorbidities, preoperative antibiotics, fixation type, and the occurrence of deep postoperative infection. RESULTS Of the 801 patients who underwent ACL reconstruction, 6 (0.75%) developed a confirmed deep infection. There were 2 confirmed deep infections in 170 autograft reconstructions (1.2%) compared with 4 confirmed deep infections in 628 allograft reconstructions (0.6%). Multivariate analysis revealed that ACL reconstruction using autograft had a nearly twice the risk of infection compared to allograft reconstructions (adjusted odds ratio, 1.83; 95% confidence interval, 0.16 to 12.94). CONCLUSIONS This study failed to find a higher rate of deep bacterial infection in ACL reconstructions when allograft tissue was used. We therefore feel that surgeons should consider allograft tissue as an alternative to autograft when there is a concern about donor-site morbidity, or for revision reconstructions. LEVEL OF EVIDENCE Level III, therapeutic retrospective comparative study.