【Abstract】Objective: To study whether the range of knee flexion (ROF) is affected by geometrical mismatch of the femoral component and the resultant change in the pos-terior condylar offset (PCO) after high-flexion posterior-sta-bilized total knee arthroplasty (TKA). Methods: One hundred osteoarthritic patients (50 males and 50 females) underwent femoral osteotomy by the ante-rior referencing technique. The PCO for each patient was measured from lateral radiographs before, during and 2 years after TKA. The thickness of the joint cartilage was mea-sured by magnetic resonance imaging before TKA and added onto the radiographic measurement. The relationship be-tween changes in the PCO and improvements in the ROF before, during and 2 years after TKA were statistically analyzed. Results: Compared with the preoperative value, the PCO was reduced by (3.45±3.28) mm after TKA, with a sig-nificantly larger reduction observed in female patients than male patients (P0.05). However, when male and female patients were analyzed separately, there was a significant positive corre-lation between PCO change and ROF improvement for both sexes at both time points (all P