Use of Hinged Implants for Multi-Stage Revision Knee Arthroplasty for Severe Periprosthetic Joint Infection: Remission Rate and Outcomes After a Minimum Follow-Up of 5 Years.

ABSTRACT

BACKGROUND: In severe periprosthetic joint infection (PJI) after total knee arthroplasty (TKA), multi-stage procedures are indicated for ongoing signs of infection after implant removal during the spacer interval of an intended two-stage exchange. In these cases, several additional debridement and spacer exchange surgeries may be necessary. Herein, we analyzed the complications, remission rate, and functional outcome after multi-stage revision arthroplasty using hinged TKAs. METHODS: Patients (n = 79) treated with multi-stage revision arthroplasty after chronic PJI of the knee were included (2010 to 2018). During the prosthesis-free interval, a static spacer containing antibiotic-loaded bone cement was implanted. The mean number of surgeries, including implant removal and revision arthroplasty, was 3.8 (range, 3 to 8). The mean duration from implant removal to revision arthroplasty was 83 days (range, 49 to 318). Complications, remission, and mortality were analyzed after a minimum follow-up of 5 years. Outcomes were assessed based on the Knee Society Score (KSS) and the Western Ontario McMasters University Osteoarthritis Index (WOMAC). RESULTS: During follow-up, 24 (30.4%) patients underwent revision surgery, with a mean time to surgical revision of 99 weeks (range, 1 to 261). After follow-up, the infection-free remission rate and overall mortality were 87.3 and 11.4%, respectively. The mean KSS was 74.3 (range, 24 to 99); the KSS Function Score was 60.8 (range, 5 to 100); and the WOMAC, 30.2 (range, 5 to 83). CONCLUSION: In difficult-to-treat cases, multi-stage revision arthroplasty showed high remission rates and low mortality after a follow-up of 5 years. The overall revision rate was comparably high, accounting for early and late reinfections most of the time. In cases of implant survival, functional outcomes comparable to those of revision hinge TKA reported in the literature can be achieved. Therefore, multi-stage procedures with additional debridement steps should be performed in cases of ongoing infections in intended two-stage procedures.