Thigh root pain alert femoral head necrosis, hip osteoarthritis, synovitis, muscle strain, lumbar disc herniation. 1. Necrosis of the femoral head: early necrosis of the femoral head, thigh root pain, walking with a limp, limited hip joint activities. 2. Osteoarthritis of hip joint: osteophyte degeneration and narrowing of joint space can cause thigh pain and limitation of hip joint activities. 3. Synovitis: Hyperplasia and hypertrophy of the synovial membrane of the hip joint and secretion of fluid may cause limitation of hip joint activities and thigh root pain. 4. Muscle strain: poor posture, such as often stilts legs can cause adductor muscle strain, thigh pain, adductor activity is limited. 5. Lumbar disc herniation: Lumbar disc herniation can radiate to the root of the thigh pain, some will have numbness. Thigh root pain can also be caused by other reasons such as urethritis and enteritis. If thigh root pain occurs and persists without relief, consult a doctor in time to clarify the specific cause of the disease, and then follow the doctor’s instructions for treatment.