Pain in half of the buttocks, like a cramp, should be considered to be produced by nerve damage or irritation. A more common condition is lumbar disc herniation, which is a herniated disc in the lumbar spine caused by a variety of reasons. The nerve roots will be stimulated by the herniated disc, which will compress the nerve roots and produce abnormal discharge, resulting in electric shock-like pain like cramps in the area innervated by the nerve roots, with the buttocks being the most commonly affected area because the sciatic nerve passes through the buttocks. In addition, half of the buttocks pain like cramp may also be due to pear muscle syndrome, local tumor disease, infectious disease and aseptic inflammation, all of which will stimulate the pear muscle, which will contract spasmodically, and the sciatic nerve will be squeezed, which will lead to abnormal discharge of the sciatic nerve, resulting in buttocks pain like cramp.