Method for determining lower limb biological force line in three-dimensional space for total knee arthroplasty

The invention relates to a method for determining a lower limb biological force line in a three-dimensional space for total knee arthroplasty. The problem of determining a lower limb biological force line for total knee arthroplasty puzzles orthopedists, and how to overcome the defects that the total knee arthroplasty is performed in a two-dimensional plane traditionally and how to improve postoperative effects become a key study point. According to the method, three-dimensional space imaging and reverse engineering technology are combined with digital medicine, and three-dimensional reconstruction of lower limb femoral head-distal femur-proximal tibia-ankle joint is achieved by medical three-dimensional visual software Simpleware on the basis of three-segment hip-knee-ankle MRI (magnetic resonance imaging) data; space fitting of the femoral head center is completed in reverse engineering processing software Geomagic and Imageware; based on the anatomical morphology of the distal knee joint, the knee joint center is determined by means of space fitting; similarly, the tibial plateau center and the ankle joint center are determined, and connection lines of the four points from the femoral head center to the ankle joint center are established three-dimensionally to obtain the biological force line of the overall lower limb, so that precise bases are provided for the total knee arthroplasty.