O-shaped legs in small children may be caused by physiological factors, but also vitamin D deficiency rickets, trauma and other factors. Different triggers, treatment methods are also different ah, including general treatment medication as well as surgical treatment. 1. Physiological factors: Because the child’s skeletal system is not yet well developed, the child may have physiological O-shaped legs, adjust the dietary structure, increase the intake of calcium from dietary sources. Adjust the dietary structure to increase the intake of calcium from dietary sources. If necessary, take calcium supplements as prescribed by the doctor. With the development of bones and muscles, it can usually be corrected on its own. 2. Vitamin D deficiency rickets: O-shaped legs caused by, to strengthen the care, reasonable diet, adhere to regular sun exposure; supplementation of vitamin D, at the same time, give the right amount of calcium, will help improve the symptoms and promote bone development. If necessary, a doctor should assess whether surgical intervention is needed to correct the deformity. 3. Trauma: For example, in the case of deformed healing of fracture, premature epiphyseal closure after epiphyseal injury, surgical treatment, such as osteotomy, semi-epiphyseal block for guided growth, should be considered in order to avoid interfering with the normal development of the limb. During the treatment, it is important to follow the doctor’s instructions to use reasonable medication, and after the surgical treatment, it is important to do a good job of postoperative care.