Origin
Outer surface of ilium behind posterior gluteal line, adjacent posterior surface of sacrum and coccyx, sacrotuberous ligament, aponeurosis of erector spinae (sacrospinalis)
Insertion
Iliotibial tract of fascia lata, gluteal tuberosity of femur
Actions
Upper part—abducts, laterally rotates thigh Lower part—extends, laterally rotates thigh, extends trunk, assists in adduction of thigh
Nerve
Inferior gluteal nerve (L5, S1, S2)
Note
This is not a postural muscle; it is not used in walking but only in forceful extension, as in running, climbing, or rising from a seated position.
