The piriformis muscle is a muscle that extends from the base of the spine to the outside of your femur/hip region. That muscle has a variety of functions including pulling your leg away from the body and rotating it outwards.
Piriformis syndrome is a condition which may be due to compression of the sciatic nerve by the piriformis muscle. Causes of piriformis syndrome include: trauma to the gluteal region and over-use injury.
Symptoms may include pain and numbness in the buttocks and down the leg. Imaging studies are not useful to diagnose piriformis syndrome and so often it requires a trained provider to determine if this may be the cause of your pain. Treatment for piriformis syndrome includes avoiding activities that cause the symptoms. Additionally, stretching, physical therapy and piriformis muscle injections can also be helpful.