Knee Arthroscopy for Wear-Induced Synovitis of a Recalled Implant Is Associated With a High Rate of Failure and Fails to Avoid Need for Revision TKA

Background: Polyethylene wear-induced synovitis and osteolysis are well-recognized complications following total knee arthroplasty (TKA) and have been of particular concern in the setting of recalled Exactech implants. While knee arthroscopy (KA) has been proposed as a minimally invasive option to address intra-articular debris and synovitis, its effectiveness in preventing disease progression and implant failure remains unclear. Purposes: The purpose of this study was to evaluate the clinical and radiographic outcomes of KA in patients with recalled Exactech TKA presenting with polyethylene wear-induced synovitis. Specifically, we assessed rates of reoperation, revision arthroplasty, and progression of osteolysis following arthroscopic intervention. Methods: A retrospective chart review was conducted on 38 patients who underwent KA after primary TKA with recalled Exactech implants between January 2022 and January 2023. Patient demographics, clinical outcomes, and radiographic and magnetic resonance imaging (MRI) findings were analyzed by a high-volume, fellowship-trained arthroplasty surgeon. Results: Within 1 year of follow-up, 4/38 patients (10.5%) underwent revision TKA, 4/38 (10.5%) patients underwent repeat KA, and 6/38 patients (15.8%) demonstrated progressive osteolysis on follow-up radiographs, resulting in an overall failure rate of 14/38 patients (36.8%). Of the remaining 30 patients who had not undergone revision TKA or repeat KA, 29 of 30 patients (96.7%) had one of the following findings: possible component loosening (5/30), progressive radiolucent lines (25/30), and worsening osteolysis on follow-up radiographs (15/30). Additionally, upon review of patient post-arthroscopy MRIs, 28/30 patients (93.3%) had documentation of persistent/progressive polymeric-induced synovitis or persistent/progressive osteolysis. Conclusion: The high failure rate reported in the current study suggests that KA with debridement is not an appropriate treatment for patients with polyethylene wear-induced synovitis and osteolysis following the implantation of a recalled Exactech TKA. Delay of the surgery can result in more severe bone defects. In patients with wear-induced synovitis but without osteolysis or implant loosening, a polyethylene insert exchange is the preferred alternative treatment. Level of Evidence: Prognostic study level IV.