Techniques for extensor mechanism reconstruction after total knee arthroplasty: Is there a clear winner?

Extensor mechanism (EM) disruption after total knee arthroplasty (TKA) is rare, but can result in devastating outcomes for patients including inability to ambulate. Disruption can occur at the quadriceps tendon, patella, or patellar tendon. This complication can be traumatic, but is often atraumatic from an iatrogenic or degenerative etiology. Primary repair for treatment of EM disruption has led to poor results with high failure rates and has mostly been abandoned. Most commonly accepted techniques center around Achilles tendon allograft reconstruction, synthetic mesh reconstruction, or other smaller options. However, to date, there is still no consensus for the optimal EM reconstructive technique due to the heterogeneity and small sample sizes of published studies. The need to identify a consistent and effective surgical technique is paramount to restore quality of life to patients who suffer from EM disruption after TKA. The purpose of this review is to describe the osteology, vasculature, and EM of the knee, identify risk factors associated with EM disruption after TKA, outline the considerations for surgical management, as well as compare and analyze the latest contributions to the literature, in particular allograft versus synthetic mesh, in the reconstruction of the EM after TKA.