XO-leg can be corrected by the following methods: first, most XO-leg in children or adolescents is caused by the imbalance of epiphysis development, then the epiphyseal plate can be fixed to make both sides of the epiphysis development balance, which can correct the XO-leg; second, the method of internal fixation of osteotomy, if the adult knee joint due to degenerative osteoarthritis or serious trauma, resulting in joint gap imbalance Third, joint replacement, if the elderly have severe degenerative arthritis or severe joint trauma, joint replacement can also be used to correct XO-leg deformity, which can play a role in treating both bone disease and deformity.