Cramps on the back side of the thigh are usually seen in the following three possibilities: first, because of lumbar disc herniation compressing the nerves, resulting in radiating pain or cramps in the muscles of the back side of the thigh innervated area, for which the most common treatment is adequate bed rest, lumbar circumference protection, and if necessary, oral non-steroidal anti-inflammatory and analgesic drugs with treatment. The second, after prolonged walking or strenuous exercise, resulting in muscle strain and inflammation of the fascia on the back side of the thigh, and then pain, which can sometimes be manifested as cramp-like pain, then sufficient bed rest, with local hot compresses and other treatment, the symptoms can be significantly relieved. The third type of pain is cramping and radiating pain in the back of the thigh, which may be caused by knee joint lesions.