&Piriformis Syndrome=The piriformis syndrome is a condition in which the piriformis muscle irritates the sciatic nerve, causing pain in the buttocks and referring pain along the course of the sciatic nerve. This referred pain, called "sciatica", often goes down the back of the thigh and/or into the lower back. Patients generally complain of pain deep in the buttocks, which is made worse by sitting, climbing stairs, or performing squats. It originates from the sacral spine and attaches to the greater trochanter of the femur. The sciatic nerve usually passes underneath the piriformis muscle, but in approximately 15% of the population, it travels through the muscle. It is thought that acute or chronic injury causes swelling of the muscle and irritates the sciatic nerve, resulting in sciatica. Patients with an aberrant course of the nerve through the muscle are particularly predisposed to this condition.