Gluteal Region Muscles

Question 1

Gluteus Maximus

Answer 1

O: Ilium posterior to posterior Gluteal Line; Dorsal Surface of Sacrum and Coccyx; Sacrotuberous Ligament
I: Most fibers end in Iliotibial Tract; Some fibers insert of Gluteal Tuberosity
N: Inferior Gluteal Nerve (L5-S2)
A: Extends thigh and assists in its lateral rotation; steadies thigh and assists in rising from sitting position

Question 2

Gluteus Medius

Answer 2

O: External Surface of Ilium between Anterior and Posterior Gluteal Lines
I: Lateral surface of Greater Trochanter of Femur
N: Superior Gluteal Nerve (L5, S1)
A: Abduct and medially rotate Thigh; Keep pelvis level when ipsilateral limb is weight-bearing and advance opposite (unsupported) side during its swing phase

Question 3

Gluteus Minimus

Answer 3

O: External Surface of Ilium between Anterior and Inferior Gluteal Lines
I: Anterior Surface of Greater Trochanter of Femur
N: Superior Gluteal Nerve (L5, S1)
A: Abduct and medially rotate Thigh; Keep pelvis level when ipsilateral limb is weight-bearing and advance opposite (unsupported) side during its swing phase

Question 4

Piriformis

Answer 4

O: Anterior surface of Sacrum; Sacrotuberous Ligament
I: Superior Border of Greater Trochanter of Femur
N: APR of S1, S2
A: Laterally Rotate extended thigh and Abduct flexed thigh; Steady Femoral Head in Acetabulum

Question 5

Obturator Internus

Answer 5

O: Pelvic Surface of Obturator Membrane and Surrounding Bones
I: Medial Surface of Greater Trochanter (trochanteric fossa) of Femur
N: Nerve to Obturator Internus (L5, S1)
A: Laterally Rotate extended thigh and Abduct flexed thigh; Steady Femoral Head in Acetabulum

Question 6

Superior Gemelli

Answer 6

O: Ischial Spine
I: Medial Surface of Greater Trochanter (trochanteric fossa) of Femur
N: Nerve to Obturator Internus (L5, S1)
A: Laterally Rotate extended thigh and Abduct flexed thigh; Steady Femoral Head in Acetabulum

Question 7

Inferior Gemelli

Answer 7

O: Ischial Tuberosity
I: Medial Surface of Greater Trochanter (trochanteric fossa) of Femur
N: Nerve to Quadratus Femoris (L5, S1)
A: Laterally Rotate extended thigh and Abduct flexed thigh; Steady Femoral Head in Acetabulum

Question 8

Quadratus Femoris

Answer 8

O: Lateral Border of Ischial Tuberosity
I: Quadrate Tubercle on Intertrochanteric Crest of Femur and area inferior to it
N: Nerve to Quadratus Femoris (L5, S1)
A: Laterally Rotates Thigh; Steadies Femoral head in Acetabulum

Question 9

Tensor Fascia Lata

Answer 9

O: ASIS, Anterior Part of Iliac Crest
I: IT Band, which attaches to Lateral Condyle of Tibia
N: Superior Gluteal Nerve (L5, S1)
A: Abduct and Medially rotate thigh, Keep Pelvis Level when single leg standing

Question 10

Obturator Externus

Answer 10

O: Margins of Obturator Foramen and Membrane
I: Trochanteric Fossa of Femur
N: Obturator Nerve (L3, L4)
A: Laterally Rotate the Thigh steadies Femoral Head in Acetabulum