Patellofemoral Joint: Femoral Component

Approximately one in five patients who undergo total knee arthroplasty (TKA) will experience postoperative pain, which serves as a contributor to decreased satisfaction after TKA. Although the exact etiology and underlying mechanism remain unknown, postoperative pain may be attributable to patellofemoral joint (PFJ) disorder, and severe PFJ injury may warrant revision surgery [1]. In the early period after its introduction, only compatibility between the femur and tibia was considered in TKA, and thorough evaluation of the PFJ was not performed. Therefore, patients frequently presented with PFJ disorders, such as postoperative patellar clunk syndrome (PCS) and anterior knee pain (AKP). In recent years, this design has been improved to avoid post-TKA PFJ injury. The goal is to realize the natural patellar glide across all ranges of motion (ROMs) of the knee joint by bringing the implant shape closer to the original PFJ shape.