Re-revision Extensor Mechanism Reconstruction Because of Nonunion and Tendon Failure After Total Knee Arthroplasty.

Extensor mechanism (EM) disruption after total knee arthroplasty (TKA) is devastating, especially in cases of re-rupture. A 67-year-old man with diabetes had patellar tendon rupture after revision TKA and then had migration of the bone block after Achilles tendon allograft with bone block (ATBB) augmentation with cerclage. A third reconstruction was performed with open reduction and internal fixation and high-strength braided suture augmentation. Five months postoperatively, the patient had regained full range of motion with intact EM and hardware. The risk of re-rupture is high in ATBB, and the primary issues in this case were nonunion and tendinous compromise. A construct that encompasses compression and buttressing of the bone block with tendon augmentation potentially addresses the risks of recurrent EM rupture in more complex cases. [ 2024;47(5):e273-e276.].