X-shaped leg alias knee valgus. Knee valgus in boys may be caused by excessive obesity, overweight, rickets, and localized fibrous bone dysplasia. The correction methods are more or less the same. Mild asymptomatic knee valgus needs no treatment; severe or symptomatic knee valgus can be corrected by exercise treatment, orthosis correction and surgery. 1. Exercise therapy: For boys with mild knee valgus, if the situation is not particularly serious and there is no structural change, you can consider exercise therapy to improve the situation, such as mobility training of the knee joint and muscle strength training, which can achieve the effect of bilaterally balanced, thus correcting the shape of the leg. 2. Orthopedic correction: If the X-shaped leg is obvious and has affected the beauty or walking posture, we should consider wearing orthopedic devices to correct it, and try to restore the normal force line of the knee joint in order to correct the purpose of leg shape. 3. Surgery: For severe knee valgus, it is usually easy to induce traumatic knee osteoarthritis, which has produced obvious structural changes. Surgical treatment, such as osteotomy, needs to be considered to rebuild the structure of the knee joint and prevent sequelae. Patients who want to undergo knee valgus correction should follow the doctor’s instructions and actively cooperate with the doctor’s treatment, so as not to delay the condition.