Piriformis syndrome is a neuromuscular disorder that occurs when the sciatic nerve is compressed or otherwise irritated by the piriformis muscle causing pain, tingling and numbness in the buttocks and along the path of the sciatic nerve descending down the lower thigh and into the leg. Diagnosis is often difficult due to few validated and standardized diagnostic tests, but one of the most important criteria is to exclude sciatica resulting from compression/irriation of spinal nerve roots, as by a herniated disk. The syndrome may be due to anatomical variations in the muscle-nerve relationship, or from overuse or strain...