The causes of hip sagging in patients are divided into physiological and pathological causes, as follows: I. Physiological causes: usually because people are more obese and have thicker accumulation of hip fat, it will easily lead to hip sagging. It may be that people who are sedentary or lack of lower limb exercise have weakened hip muscle elasticity or even atrophy, which leads to hip sagging. In addition, after the gradual degeneration and atrophy of the hip muscles of the elderly, hip sagging will also occur. Second, pathological reasons: usually the hip muscles have nerve abnormalities, such as diseases related to the lumbar spine, which compress the nerve roots of the lower limbs, resulting in frequent numbness and weakness of the lower limbs, leading to pathological muscle atrophy and hip sagging. In addition, it may be a fracture of the pelvis or a fracture of the lower limb, which causes muscle atrophy due to the lack of activity of the lower limb for a long time, and hip sagging may also occur.