Human Movement Science & Functional Anatomy of the:
Deep Rotators of the Hip:
- Quadratus Femoris
Note: Piriformis discussed separately
by Brent Brookbush MS, PES, CES, CSCS, ACSM H/FS
Deep Rotators of the Hip via Visiblebody.com - http://info.visiblebody.com/Portals/189659/images/Lateral-rotator-muscles-hip-gluteal.png
Anatomy (in order from superior to inferior):
Whats in a name:
- Obturator - from the latin root obturare, meaning to "block an opening." The obturators "block" the obturator foramen of the ischium.
- Gemellus - is a diminutive of the Latin word geminus (think of the zodiac sign "Gemini") meaning a twin. There are two gemelli muscles similar in size shape and function.
- Quadratus Femoris - Latin root quadratus means square shaped and femoris is obviosely in reference to the femur. "A square shaped muscle on the femur"
- Origin: External surface of the spine of the ischium (11).
- Insertion: With a common tendon shared by the obturator internus and gemellus ingerior into the medial surface of the greater trochanter of the femur.
- Nerve: Nerve to the gemellus superior via the sacral plexus originating from Nerve roots S1, S2 and sometimes L5
- Action: External rotation and horizontal abduction of the hip
- Origin: Internal or pelvic surface of the obturator membrane and margin of the obturator foramen, pelvic surface of the ischium posterior and proximal to the obturator foramen, and to a slight extent the obturator fascia (11).
- Insertion: With a common tendon shared by the gemelli into the medial surface of the greater trochanter of the femur, proximal to the trochanteric fossa.
- The obturator internus makes a nearly 90º as it passes through the lesser sciatic notch which is