If a patient has thigh root cramps and pain, the causes triggered include inguinal ligament strain, femoral head necrosis, hip muscle strain, and pear-shaped muscle syndrome, etc., as follows: i. Inguinal ligament strain: easily leads to thigh root cramps and pain. Femoral head necrosis: especially after the femoral head necrosis, triggered by osteonecrosis under the cartilage surface of the femoral head, after the cystic change situation, easily lead to the root of the thigh cramps, pain. Third, the hip muscle strain: will also lead to thigh root cramps, pain. Fourth, the pear-shaped muscle syndrome: in the acute attack will also appear thigh root cramps, pain. Therefore, after a patient develops thigh root cramps and pain, it is important to consult a doctor to see what triggers it. Treat the cause to promote the reduction and recovery of thigh cramps and pain, in order to restore the normal force activity of the lower limbs.