Sometimes, hip and leg pain can be caused by a pyriformus syndrome. It will not show up on a CT or MRI because it does not involve a disc or boney formation. The sciatic nerve forms from nerves which come from several levels of the lumbar and sacral spine which nerge to form this large nerve which feeds the pelvis, hip and leg. After the nerve is formed, it passes through the area of the buttock. The bottom most muscle of the buttock area lies under the gluteous maximus and is called the pyriformus nerve which stretches from the forward pelvic implantation and implants on the coccyx in the rear. IT is a large, important muscle. Eighty percent of the time, the muscle actually has a small slit in it which permits the sciatic nerve to run through the muscle and on into the leg. Twenty percent of the time, the nerve runs under the muscle. If the muscle is stretched or misplaced by injury or problems in the pelvis, then the nerve can be hendered or stretched as well and this can result in pain, numbness, burning, etc. in the hip, buttock, pelvis, and leg. This just might be your problem.