The John N. Insall Award: Reduced Reinfection Rate With Intraosseous Vancomycin Administration at Reimplantation in Two-Stage Revision Total Knee Arthroplasty

Background Recurrent periprosthetic joint infection (PJI) after two-stage exchange total knee arthroplasty (TKA) is associated with increased morbidity and mortality. Intraosseous (IO) vancomycin has been shown to reduce PJI rates in primary and aseptic revision TKA, but its role in two-stage revision for infection remains unknown. This study aimed to compare reinfection rates following IO vancomycin versus intravenous (IV) antibiotic prophylaxis at the time of reimplantation. Methods We conducted a retrospective cohort study of 252 patients who underwent two-stage revision for infected TKA at a single institution between July 2016 and March 2025, of whom 101 received IO vancomycin and 151 received IV antibiotics. Patients in the IO group received IV cefazolin plus 500 mg of vancomycin via IO infusion, while those in the IV group received IV cefazolin with or without IV vancomycin, according to surgeon preference. There were no significant differences in average age, body mass index, or sex between the two groups. Most cases involved chronic infection (92%), with coagulase-negative staphylococci (23%) and methicillin-sensitive Staphylococcus aureus (17%) as the most common organisms. Reinfection rates were compared between groups. Results Reinfection rates were significantly lower in the IO vancomycin group at one year (6 versus 14%, P = 0.049), two years (9 versus 22%, P = 0.025), and three years (16 versus 30%, P = 0.045) after reimplantation. Logistic regression analyses showed that patients who did not receive IO vancomycin at reimplantation had a nearly threefold increased odds of reinfection at three years (odds ratio 2.9, P = 0.025). Of the 44 reinfections, 39 yielded a positive culture, 33 of 39 (85%) of which were sensitive to vancomycin. Conclusions Intraosseous vancomycin administration at the time of reimplantation during two-stage revision TKA was associated with significantly reduced rates of recurrent PJI compared to IV antibiotic prophylaxis alone.