Origin: Ischial tuberosity
Insertion: Obturator internus tendon
Nerve: Nerve to Quadratus femoris (L4, L5, S1)
Action: Rotates laterally thigh
The Gemelli are two small muscular fasciculi, accessories to the tendon of the Obturator internus which is received into a groove between them.
The Gemellus inferior arises from the upper part of the tuberosity of the ischium, immediately below the groove for the Obturator internus tendon. It blends with the lower part of the tendon of the Obturator internus, and is inserted with it it into the medial surface of the greater trochanter. Rarely absent.