PiriformisThe structure indicated is the piriformis muscle. The piriformis muscle is one of the muscles of the gluteal region. The muscles in the gluteal region are divided into a superficial and deep group. There are four muscles of the superficial group:
- Gluteus maximus
- Gluteus medius
- Gluteus minimus
- Tensor fasciae latae
- Gemellus superior
- Gemellus inferior
- Quadratus femoris
- Obturator internus
- Greater sciatic foramen above the piriformis (suprapiriform foramen)
- Greater sciatic foramen below the piriformis (infrapiriform foramen)
Origin: Anterior portion of lateral process of sacrum. Gluteal surface of ilium at border of greater sciatic notch
Insertion: Superior border of greater trochanter
Action: Lateral rotation of hip. Assists abduction of hip when hip is flexed.
Innervation: Nerve to piriformisLearn more about the anatomy of the gluteal muscles in this tutorial.