The Deep Lateral Rotator Group is composed of the following six muscles (from superior to inferior):
- Superior gemellus
- Obturator internus
- Inferior gemellus
- Obturator externus
- Quadratus femoris
- The deep lateral rotator group attaches from the sacrum (piriformis) and the pelvic bone (the rest of the group) to the (or nearby the) greater trochanter of the femur.
- Note: The obturator externus sits deeper than the other muscles of the group, lying wholly or mostly deep to the quadratus femoris.
- As a group, the deep lateral rotators laterally rotate the thigh at the hip joint and contralaterally rotate the pelvis at the hip joint.
- If the thigh is first flexed to 90 degrees, the deep lateral rotators can horizontally extend (horizontally abduct) the thigh at the hip joint.
- Note: If the thigh is first flexed (approximately 60 degrees or more), the piriformis changes to become a medial rotator of the thigh at the hip joint instead of a lateral rotator.