Fig. 4.

Illustration of the arKA technique. The tibial cutting guide was positioned at 3° varus to the vertical line of the mechanical axis of the tibia in coronal plane. On the femoral side, the resection of the femur was appropriate varus to the line perpendicular to the mechanical axis of the femur, aiming to restore the medial joint height and obtain an approximate rectangular gap in the extension position without ligament release. For flexion gap, external rotation of the femoral component was regulated by soft tissue tension. In addition, a wider flexion lateral gap was produced. Abbreviations: mFA mechanical femoral axis; mTA mechanical tibial axis; FR femoral resection; TR tibial resection; MJH medial joint height; LJH lateral joint height