Effect of Failed Debridement, Antibiotics, and Implant Retention on Subsequent Two-Stage Reimplantation for Periprosthetic Joint Infection Following Total Knee Arthroplasty: A Retrospective Cohort Study

Background: Periprosthetic joint infection (PJI) following total knee arthroplasty (TKA) is a serious complication associated with substantial morbidity and healthcare costs. Although two-stage revision arthroplasty is widely accepted as a standard treatment, debridement, antibiotics, and implant retention (DAIR) is frequently attempted as a less invasive initial strategy. However, the impact of failed DAIR on the outcomes of subsequent two-stage revision remains controversial. Methods: This retrospective cohort study included patients who underwent two-stage revision arthroplasty for PJI following TKA at a single institution between 2005 and 2019, involving 84 knees at an average follow-up of 5.1 ± 3.3 years. Outcomes were compared between patients with a history of failed DAIR (F-DAIR group, n = 23) and those who underwent direct two-stage revision without prior procedures (DTSR group, n = 61). Treatment failure rates and associated risk factors were analyzed. Results: There was no significant difference in treatment failure rates between the F-DAIR and DTSR groups (4.3% vs. 9.8%, respectively; p = 0.668). Cox regression suggested that PJI type (acute vs. chronic) and diabetes mellitus were associated with treatment failure. Conclusions: In this retrospective cohort, prior failed DAIR was not associated with a statistically significant reduction in the success of subsequent two-stage revision arthroplasty. These findings may support consideration of DAIR as an initial treatment option in carefully selected patients; however, cautious interpretation is warranted because of the retrospective design, limited sample size, baseline imbalance, and small number of failure events. Therefore, the findings should be considered hypothesis-generating rather than definitive comparative evidence.