| Latin | Musculi gemelli |
|---|---|
| Origin |
|
| Insertion |
|
| Action |
|
| Nerve | Superior gemellus: nerve to obturator internus; inferior gemellus: nerve to quadratus femoris (L4–S2 (superior L5–S2; inferior L4–S1)) |
| Group | Deep hip rotators |
| Name | Latin gemellus, a diminutive of geminus, 'twin' — the two muscles are a matched pair. |
Palpation
- Client prone with a bolster under the ankles; stand beside the hip.
- Find the greater trochanter and the ischial tuberosity. The gemelli lie in the space between them, just above quadratus femoris and below piriformis, under gluteus maximus.
- Sink in slowly with flat fingers. The gemelli cannot be felt apart from obturator internus; feel for a deep, firm band running across towards the trochanter.
- Bend the client's knee to 90° and ask them to press the foot inwards against light resistance (hip lateral rotation); feel the deep band firm up.
The superior and inferior gemelli are two thin strips of muscle that sit on either side of the Obturator internus tendon, like a pair of helpers. The tendon lies in a groove between them, and both blend into it before it reaches the Greater trochanter. Their job is to add power to obturator internus where its tendon bends sharply around the back of the pelvis.
They are two of the six Deep hip rotators. In a massage you cannot separate them from their neighbours: they lie under Gluteus maximus, between Piriformis above and Quadratus femoris below. Work on them is part of general deep work behind the hip rather than a separate step.
The two gemelli have different nerve supplies. The superior gemellus shares the nerve to obturator internus; the inferior gemellus shares the nerve to quadratus femoris. Note that the Wikipedia “Gemelli muscles” infobox lists the origin as the ischiopubic ramus and obturator membrane, which is the origin of obturator internus; the article text (ischial spine and ischial tuberosity), used above, agrees with the “Lateral rotator group” article.