First, the judgment standard of O-leg is generally based on the two indicators of normal knee distance and active knee distance to determine the severity of O-leg. The so-called normal knee distance refers to the distance between the inside of the knee joints when the ankles are close together and the legs and knees are relaxed when standing upright. Active knee distance refers to the distance between the medial side of the knee joints when the ankles are close together and the legs and knee joints are forced inward while standing upright. According to the size of the normal knee distance and active knee distance, “O-leg” is divided into mild, moderate and severe. 1.The normal knee distance below 3 cm is mild; 2.The normal knee distance between 3-10 cm is moderate; 3.The normal knee distance above 10 cm is severe. Surgery for O-leg correction Surgery is suitable for patients with very severe O-leg, or those who have osteoarthritis and joint pain. The advantage of surgery is that it is a passive treatment and the correction is immediate and does not require persistence and insistence. The disadvantage is that the surgical technique is different and most of them require bone amputation, which is painful and risky and expensive. 1.External fixator plus tibial tuberosity inverted U-shaped osteotomy. The advantages of this method are: osteotomy is simple, safe, fast bone healing, not prone to delayed healing, the use of external fixator is easy to grasp the angle of plastic correction, can make the bone healing angle accurate, and easy to adjust. Patients can move on the ground during the treatment process, and the muscles of the lower limbs will not atrophy. 2, tibial tuberosity inverted U-shaped osteotomy, postoperative external fixation of tubular plaster. External fixation treatment of O-leg Knee inversion deformity (D, O-leg) is a common deformity of the lower limbs, the patients are mostly adolescents, and it can involve one or both lower limbs, the causes include rickets (divided into child type and juvenile type), epiphyseal necrosis or abnormal epiphyseal development. The knee entropion not only affects the appearance, but also causes a shift in the line of gravity of the lower limbs, which can lead to ligamentous laxity on the tension side, ligamentous contracture on the pressure side, degenerative arthritis, patellar dislocation and patellar tenderness, and can cause various symptoms. Although the diagnosis is not difficult, it is an important clinical task for the orthopedic surgeon to find the cause to clarify the site, direction and severity of the deformity and to select the appropriate treatment. In older cases and those with severe deformity, orthopedic surgery is often required, and satisfactory orthopedic results depend on a well-designed surgical plan before surgery. Knee entropion is associated with internal tibial rotation deformity, which can lead to limb shortening unilaterally and short stature bilaterally. They should be corrected at the same time. For special causes of entropion (e.g., low phosphorus anti-D reniform rickets), medical treatment is often required, and after stabilization, osteotomy orthopedic surgery is feasible. Traditionally, the treatment of internal derangement of the knee is often done by using a lateral calf incision, wedge-shaped osteotomy of the upper tibia, oblique osteotomy of the fibula in different planes, and then crossed internal fixation with L-shaped pegs or Kirschner pins, and external fixation with plaster tubes. Four, X-leg judgment criteria X-leg refers to the two feet side by side, first of all, both knees touch together, while the two heels are not close together, walking two knees fighting each other touch gait. Only the knees can touch after the feet are together, and there are gaps between the thighs and calves. Five, X-legged harm X-legged effect knee joint is the earliest wear parts is the patella, this is because the patella is the lower limb flexion and extension of the power “force” device, that is, a “fulcrum” when extending the knee joint. This is because the patella is the “fulcrum” of the lower extremity when extending the knee joint. X-leg is caused by the constant friction between the legs, which causes some damage to the patella. X-leg has the greatest impact on the knee joint, which has a heavy task and relatively poor nutrition, so the incidence of knee strain and sports injuries ranks first among all the joints in the human body, “to put it ‘horribly’, our knee joint only has about 15 years The rest of the time, there are different types of pain for different reasons. And the so-called X-leg for some people may feel no impact, but those who have really studied it will find that the X-leg for people is still a very big impact, first of all, X-leg people, they will not only than the normal people to wear pants much higher chance, but also the speed of running is also affected to some extent. So X-leg has a very big impact on the joints. 1.Before 15 years old: the knee joint is in the developmental stage, and the growing pains in adolescence mostly occur near the knee joint. 2, 15 ~ 30 years old: the knee joint is in a “perfect state”, and it works tirelessly. As long as the knee joint tissue is not damaged, it is basically not felt. 3, 30 ~ 40 years old: patellofemoral cartilage has produced early mild wear and tear, there will be a vulnerable period, short-term knee pain, lasting a few weeks to a few months, some people will not even notice. Patellofemoral cartilage is a 3-5 mm thick layer of hyaline cartilage in the human knee joint that cushions the knee joint from the impact of movement. However, because the patellar cartilage has no nerve distribution, it will only sound an “early warning signal” once during the vulnerable period before the full layer wears out, and strenuous exercise should be avoided during this period. From this time on, the use of the knee joint can no longer be arbitrary. 4. 40-50 years old: After walking long distances, the inside of the knee joint tends to become sore and painful, which is relieved by rubbing it with your hands. In the knee joint, the role of the meniscus is to cushion vibration and maintain stability. Since 60% of the body weight is supported by the medial side of the knee joint, degeneration of the medial meniscus occurs earlier. Because of the nerve distribution in the meniscus, people can feel soreness and pain during the degeneration process. This is a reminder that it’s time to start taking care of your joints. 50 years of age and older: you will feel significant pain in your knee joint because the patellar cartilage has reached the end of its “useful life”, the cartilage is worn down and arthritis has developed. This is the time to conserve the use of the joint, reduce strenuous exercise, especially stairs and climbing, and use crutches if necessary to reduce the pressure on the knee joint. In old age, the joints become weaker in comparison, and the effects of X-leg on the joints are quite serious. Therefore, this matter should never be underestimated. If the distance between the inner ankles is 3-6cm, non-surgical treatment is available: massage the muscles of the outer thighs during the day, and make the two ankles and femoral condyles close together at night after the child falls asleep and use bandages or splints to gradually correct the problem; supplement calcium and vitamin D, and get more sunlight. If the distance between the inner ankles is 6-9cm, surgical treatment is available: 1. lateral epiphyseal block of the knee joint; 2. supracondylar osteotomy of the femur.