Outcomes After Definitive Knee Resection Arthroplasty for Recurrent Periprosthetic Joint Infection.

Background: Knee resection arthroplasty (KRA) is performed as definitive treatment for recurrent periprosthetic joint infection (PJI). This study aims to evaluate infection eradication and functional outcomes following KRA as a definitive treatment of PJI. Methods: We reviewed all KRAs performed between 2002 and 2022. We identified 28 knees (27 patients) treated with definitive KRA for recurrent PJI. Primary outcomes included infection eradication, ambulatory status, and ambulatory aid use. Failure to eradicate infection was defined as any reoperation for infection. Ambulation was defined as any level of weight-bearing mobility using assistive devices, such as a walker. Results: The mean age at KRA was 72 years and average follow-up was 22 months. Patients had on average 3 knee operations prior to KRA. Of the 28 infections, 79% were eradicated by KRA. Of the remaining 6 persistently infected knees, 4 required an average of 4 irrigation and debridement to eventually control infection, resulting in 93% of infections eradicated overall. At latest visit, 33% of patients were on chronic antibiotic suppression. A total of 67% of patients could ambulate. Most patients (85%) required knee-ankle-foot orthoses for instability. Subsequent knee fusion was chosen by 3 patients. A patient with bilateral KRAs died within 90 days of surgery. The overall reoperation rate for KRA patients was 29%, and the overall mortality rate was 15%. Conclusions: Definitive treatment with KRA demonstrated effectiveness in eradicating infection, although with moderate rate of reoperation. Postoperatively, most patients could ambulate with assistive devices. The KRA is an effective alternative for knee salvage when managing chronic, recalcitrant PJI. Level of evidence: IV, case series.