Gluteal Region: Origins, Insertions, Innervations, and Actions

Gluteus Maximus: Origin

• External surface of ilium on posterior gluteal line

• Iliac crest

• Dorsal sacrum and coccyx

• Sacrotuberous ligament

Gluteus Maximus: Insertion

• Most fibers insert into IT band into lateral condyle of tibia

• Some fibers insert on the gluteal tuberosity of femur

Gluteus Maximus: Innervation

• Inferior gluteal nerve

  • L5, S1, S2

Gluteus Maximus: Action

• Extends thigh especially when standing up

• Externally rotates thigh

Gluteus Medius: Origin

• External surface of ilium between the posterior and anterior gluteal lines

Gluteus Medius: Insertion

• Lateral greater trochanter of the femur

Gluteus Medius: Innervation

• Superior gluteal nerve

  • L4, L5, S1

Gluteus Medius: Action

• Abducts thigh

• Internally rotates thigh

• Steadies pelvis

Gluteus Minimis: Origin

• External surface of ilium between the anterior and inferior gluteal lines

Gluteus Minimis: Insertion

• Anterior surface of greater trochanter of the femur

Gluteus Minimis: Innervation

• Superior gluteal nerve

  • L4, L5, S1

Gluteus Minimis: Action

• Abducts thigh

• Internally rotates thigh

• Steadies pelvis

Piriformis: Origin

• Anterior surface of sacrum

• Sacrotuberous ligaments

Piriformis: Insertion

• Superior border of greater trochanter of femur

Piriformis: Innervation

• Nerve to piriformis

  • Ventral rami of S1 and S2

Piriformis: Action

• Externally rotates extended thigh

• Abducts flexed thigh

• Steadies femoral head in acetabulum

Obturator Internus: Origin

• Medial surface of obturator foramen and membrane

Obturator Internus: Insertion

• Medial surface of greater trochanter of femur or trochanteric fossa

Obturator Internus: Innervation

• Nerve to obturator internus

  • L5, S1

Obturator Internus: Action

• Externally rotates extended thigh

• Abducts flexed thigh

• Steadies femoral head in acetabulum

Superior Gemellus: Origin

• Ischial spine

Superior Gemellus: Insertion

• Medial surface of greater trochanter of femur or trochanteric fossa

Superior Gemellus: Innervation

• Nerve to Obturator Internus

  • L5, S1

Superior Gemellus: Action

• Externally rotates extended thigh

• Abducts flexed thigh

• Steadies femoral head in acetabulum

Inferior Gemellus: Origin

• Ischial tuberosity

Inferior Gemellus: Insertion

• Medial surface of greater trochanter of the femur or trochanteric fossa

Inferior Gemellus: Innervation

• Nerve to quadratus femoris

  • L5, S1

Inferior Gemellus: Action

• Externally rotates extended thigh

• Abducts flexed thigh

• Steadies femoral head in acetabulum

Quadratus Femoris: Origin

• Lateral border of ischial tuberosity

Quadratus Femoris: Insertion

• Quadrate tubercle on intertrochanteric crest of femur and inferior to it

Quadratus Femoris: Innervation

• Nerve to Quadratus Femoris

  • L5, S1

Quadratus Femoris: Action

• Externally rotates thigh

• Steadies femoral head in acetabulum