The outcome of infected total knee arthroplasty: culture-positive versus culture-negative.

Abstract

We studied the outcome in culture-positive and culture-negative infected total knee arthroplasty (TKA). We retrospectively reviewed 140 patients with culture-positive and 102 patients with culture-negative infected TKAs. We determined the infection control rate and clinical outcome after repeated debridement, and repeated 2-stage TKA in the culture-positive and culture-negative groups. The mean follow-up was 9.3years (range 5-14years) in the culture-positive group and 10.6years (5-22) in the culture-negative group. The overall infection control rate was 56% in both groups after the first treatment. The overall infection control rate was 90% in the culture-positive group and 95% in the culture-negative group. A functional knee was obtained in 90% in the culture-positive group and 95% in the culture-negative group. The data suggest that treatment according to the types of infection in both culture-positive and culture-negative groups after TKA controlled infection and maintained functional TKA with a firm level of fixation for most patients. Repeated debridement and repeated two-stage exchange TKA further improved infection control rates after the initial treatment and increased the likelihood of maintaining a functional TKA.