Bending of the leg joints usually needs to be judged according to different age groups, and its correction methods generally include manipulative massage, osteotomy surgery, joint replacement and so on. 1. Children: For children under one year of age in particular, when the leg bends, i.e., their knee joints have inversion or eversion, it can generally be corrected through the use of manipulative massage techniques, as well as sports rehabilitation at the same time to correct the lower limb’s line of force. Because children are more flexible, often through conservative treatment, you can achieve the desired results. 2. Adults: When adults experience inversion or valgus of the knee joint, surgical treatment, including orthopedic osteotomies of the distal femur or proximal tibia, can be considered to correct the line of force. 3. Elderly: When an elderly person develops an inversion or eversion of the knee joint due to degenerative osteoarthritis, artificial joint replacement surgery can often be considered to correct the line of force. That is, there are often different treatments based on correcting leg joint flexion in different age groups, and the means of treatment needs to be determined after medical examination.