The piriformis is a flat pyramid-shaped muscle that lies parallel to the gluteus medius muscle's back margin and underneath the gluteus maximus muscle. The muscle passes through the greater sciatic foramen out of the pelvic region and to the upper part of the greater trochanter. It takes up the most area in the greater sciatic foramen. It is a small muscle when compared to other muscles of the region. The piriformis helps rotate the hip and works with rotators such as the obturator externus and the gemellus inferior. It will rotate the thigh while extended and will abduct, or pull inward, the thigh when flexed. The close nature of the piriformis muscle to the sciatic nerve, which is the largest nerve in the human body, can cause pain in some individuals. This pain can run from the buttocks to the lower back. Treatment for a strain or tear of this muscle includes deep tissue massage and anti-inflammatory medication, which reduces swelling around the sciatic nerve.
Written and medically reviewed by the Healthline Editorial Team
In Depth: Piriformis