摘要Total knee arthroplasty(TKA)is an effective treatment for severe knee arthritis.However,TKA is more challenging when that arthritis is associated with femoral deformity that has resulted in irregularity of the canal and variation in anatomic landmarks.1 In such cases,it is difficult to restore the mechanical alignment of the lower limb using intramedullary instruments.Shao et al2 have reported that computer-navigated TKA has satisfactory early clinical outcomes in patients with severe osteoarthritis combined with extra-articular femoral deformity.In navigated surgery,the distal femoral osteotomy is performed with respect to the mechanical alignment of the femur instead of that of the femoral canal.Therefore,computer-assisted navigation can be used to accurately reestablish mechanical alignment in patients with deformed femurs who do not require femoral osteotomy.