The causes of thigh pain include the following: first, lumbar spine diseases, when the lumbar disc herniation is high lumbar disc herniation, such as the 2nd-3rd lumbar spine, 3rd-4th lumbar spine, there will be pain in the front side of the thigh, which can be accompanied by numbness, then CT and MRI of the lumbar spine should be conducted for early diagnosis and treatment; second, thigh fasciitis, when due to exertion or cold, the thigh fascia can have chronic aseptic inflammation. When chronic aseptic inflammation of the thigh fascia occurs due to strain or cold, the pain of the thigh fascia can occur, which should be diagnosed by early physical examination; third, hip joint disease, when the hip joint has femoral head necrosis or impingement syndrome, the pain of the inner thigh or the anterior or posterior side can occur, which should be diagnosed by X-ray and nuclear magnetic examination of the hip joint; fourth, the lesion of the greater trochanter. Fourth, the lesion of the greater trochanter, when the greater trochanter has bursitis or the popping hip, there will also be pain in the proximal lateral thigh, which should be diagnosed and treated by early physical examination and related tests.