Piriformis: The piriformis is a muscle in the gluteal region of the lower limb. It is one of the six muscles of the lateral rotator group. The piriformis muscle is a key landmark in the gluteal region. It is the most superior of the deep muscles.
Origin: Originates from the anterior surface of the sacrum. It then travels infero-laterally, through the greater sciatic foramen.
Insertion: It attaches to the greater trochanter of the femur.
Function: Lateral rotation and abduction.
Nerve Supply: Nerve to piriformis.