There are several possible causes of pain in the thigh root when walking: first, muscle strain, if the strain of the inner thigh muscles, there is often pain in the thigh root. Second, hip impingement syndrome, hip impingement syndrome is due to the impact of the head and neck of the femur and acetabulum, resulting in glenoid lip injury, will cause significant pain in the thigh root when walking, especially in flexion pain is very significant. Third, the impact of the femur and the sciatic bone causes pain at the root of the thigh when walking. If the small trochanter of the femur and the sciatic bone are impacted, it will lead to muscle damage and even nerve damage, resulting in pain at the root of the thigh, accompanied by numbness and pain in the lower limbs, which can be radiated to the calf or the back of the foot, which should be further diagnosed and treated by MRI.