One-Stage Revision Total Knee Arthroplasty for Chronic Periprosthetic Joint Infection Requiring Gastrocnemius Flap Reconstruction: A Feasibility Study Using Propensity Score Matching.

ABSTRACT Background A one-stage revision total knee arthroplasty (TKA) has been increasingly adopted for the treatment of chronic periprosthetic joint infection (PJI) in specialized centers. However, patients who require soft-tissue reconstruction with a gastrocnemius flap are often excluded from one-stage strategies because soft-tissue deficiency is considered a marker of advanced disease. Data evaluating the impact of flap reconstruction within a one-stage revision strategy remain limited. Methods This single-center retrospective study analyzed prospectively collected data from patients undergoing one-stage revision TKA for chronic PJI between 2018 and 2023. Patients treated with gastrocnemius flap reconstruction were compared with those who did not undergo flap coverage. A propensity score–matched analysis was performed to contextualize outcomes between groups. The primary outcome was treatment failure, defined as relapse, new infection, or infection-related reoperation. Secondary outcomes included flap-related complications. A total of 116 patients were included, of whom 49 underwent gastrocnemius flap reconstruction. After propensity score matching, 41 matched pairs were analyzed. Results Reinfection-free (P = 0.56), relapse-free (P = 0.37), and new-infection–free (P = 0.19) survivals did not differ significantly between groups. Reinfection-free survival in the matched cohort was 72.5% at two years. Polymicrobial infections were more frequent in the flap group (9.8 versus 19.5%). All gastrocnemius flaps remained viable, and no flap-related surgical revisions were required. Conclusion In this propensity score–matched cohort of patients undergoing one-stage revision TKA for chronic PJI, the addition of gastrocnemius flap reconstruction was feasible in cases of severe soft-tissue compromise and was not associated with an obvious additional deterioration in infection-related outcomes. These findings suggest that, in specialized centers, the need for gastrocnemius flap reconstruction should not automatically preclude consideration of a one-stage revision strategy.