O-leg shape, or o-shaped leg, the formation of the cause is more complex, there is no quick way to change, serious cases, may need orthopedic surgery or artificial knee replacement surgery. Children with o-shaped legs is a normal phenomenon in the process of development, minor without special treatment, with growth and development, generally can be self-corrected. If it is caused by calcium deficiency, supplement calcium and vitamin D, wear orthopedic shoes or use orthopedic braces, it usually takes 2~3 months to recover gradually. If it is congenital or developmental o-shaped leg in adults, which cannot be corrected by oneself, tibial osteotomy orthopedic surgery can be applied if there are indications for surgery. If the lower limb force line abnormality is caused by joint degeneration, secondary o-shaped leg with knee pain and activity limitation, tibial osteotomy orthopedic surgery or artificial knee replacement surgery can be applied to change the inversion of the knee joint. So changing o-shaped leg needs different treatment methods according to the specific situation, and it takes a period of time for complete recovery.