Fig. 2

Intraoperative measurement of the PFP in the left knee. Prior to patellar osteotomy, we marked the center, the most proximal and most distal points of the patellar median ridge, and the points where the mediolateral axis of the patella intersected both ends of the patella. The marked points were used as landmarks after patellar osteotomy (A). We adjusted the center of the custom-made patellar component to the center of the resected patellar median ridge; additionally, we aligned the medial and lateral pressure sensors embedded in the patellar component with the mediolateral axis of the patella (B). PFP patellofemoral pressure