Underestimation of osteolysis in posterior stabilized total knee arthroplasty

Periprosthetic osteolysis in total knee arthroplasty (TKA) has become a significant problem. Routine surveillance is warranted to detect problems that may not be symptomatic. The goal of these radiographs is to detect arthroplasty-related bone loss at an early stage to implement strategies to limit its extension. In a posterior cruciate-retaining (PCR) implant, anteroposterior (AP) and lateral radiographs usually suffice; however, in a posterior stabilized (PS) implant, the condylar pillars of bone are obscured on routine views. The purpose of this study was to show the extent to which condylar osteolysis can be underestimated on routine radiographs.