Knee Arthrodesis Outcomes After Infected Total Knee Arthroplasty and Failure of Two-stage Revision With an Antibiotic Cement Spacer

BACKGROUND: Reinfected total knee arthroplasty can be managed with a second two-stage exchange or a knee arthrodesis procedure. METHODS: Twenty-three patients with knee arthrodesis after failed exchange arthroplasty for infection were reviewed. Patients were managed with a staged protocol of implant extraction, débridement, and implantation of an antibiotic spacer, with subsequent arthrodesis. Follow-up averaged 40.4 months, with a minimum of 1 year. RESULTS: Bony union with eradication of infection was achieved in 20/23 knees. Sixteen of the 20 patients were able to ambulate with minimal pain. The average time to union was 11.3 months, and the average leg length discrepancy was 4.85 cm. The average Knee Society Score after arthrodesis was 44, and the average visual analog scale pain score was 1.73. Three patients underwent above-knee amputation. DISCUSSION: Knee arthrodesis performed for persistent periprosthetic infection allowed for eradication of infection and union in 87% of the patients, creating a stable knee fusion.