The Utility of Flap Coverage for Limb Salvage in Patients With Severe Prosthetic Joint Infections of the Knee Requiring Implant Exchange

Abstract

Background Prosthetic joint infection (PJI) is a challenging complication of knee arthroplasty, which can require amputation in severe cases. This study analyzes the utility of flap reconstruction in PJIs requiring hardware removal and extensive soft tissue debridement. Methods This was a retrospective analysis of patients who were treated according to a multistage extremity salvage protocol between 2018 and 2022. The protocol involved at least 3 planned surgeries including (1) hardware removal with antibiotic spacer placement and soft tissue debridement, (2) spacer exchange with flap coverage, and (3) hardware reimplantation with simultaneous or delayed extensor mechanism reconstruction. All patients had large periprosthetic tissue defects that would necessitate an amputation if not reconstructed. Primary outcomes were extremity salvage and successful defect coverage. Results Fifty-two patients (25 female) underwent 62 reconstructions (52 primary, 10 salvage). Flap techniques included pedicled muscular (n = 32), fasciocutaneous (n = 4), combined muscular and fasciocutaneous (n = 2), and free flaps (n = 24). Overall rate of successful defect coverage was 95% (98% in primary and 80% in salvage reconstructions). At a median follow-up of 11 months, 41 patients completed the treatment protocol with a 68% (n = 28) extremity salvage rate (reimplantation arthroplasty, n = 15; permanent knee fusion, n = 13). On the multivariate model including demographic factors, defect size, and flap type, no single factor independently predicted limb salvage. Conclusions Alongside intensive orthopedic surgical treatment, flap coverage may aid in extremity salvage in severe knee PJIs by reestablishing healthy soft tissue coverage and allowing reimplantation arthroplasty. We recommend a multispecialty approach including plastic surgeons for this challenging condition.