The pelvic tilt is a deformity caused by the front and back joint of the pelvic ring, rotation and upper body displacement, which occurs because of congenital development or long-term abnormal sitting posture, spinal column, long and short legs, trauma, etc. Mild pelvic tilt has no obvious symptoms, such as poor sitting posture, etc., which has little impact, but serious pelvic tilt will cause serious clinical symptoms and also The pelvic tilt is relatively obvious, especially if one leg is long and one leg is short due to work injury or trauma. Severe pelvic tilt, long-term will lead to uneven force on the lower extremities, resulting in ankle, knee, etc., as well as changes in the function or structure of the spine, causing numbness and pain, these clinical manifestations, mild can be changed by increasing the shoes or changing the sitting posture, through the situation. If serious, we must look for the cause, such as serious two lower limbs are not the same length, causing to come to the pelvic tilt, we need to carry out limb lengthening surgery, which requires a visit to the orthopedic department, with a circular external fixation frame, the short leg may be bone sawing, and then slowly lengthened every day, usually about 1mm a day, until the two legs are pulled to the same length, it is possible to solve the problem. Therefore the self-correction method of pelvic height is only for the relatively mild case of double lower limbs with different lengths and mild pelvic tilt with sitting problems.