Myology of the Hip and Pelvis

Question 1

Iliacus

Answer 1

Anterior hip muscle.

• Origin: Iliac fossa.
• Insertion: Lesser trochanter.
• Role: Hip flexion, hip external rotation.
• Innervation: Femoral nerve.

Question 2

Psoas Major

Answer 2

Anterior hip muscle.
- Origin: Vertebral bodies T12-L5 and intervertebral discs.
- Insertion: Lesser trochanter.
- Role: Hip flexion, hip external rotation, lumbar extension and
pelvic anterior tilt.
- Innervation: Anterior rami of lumbar plexus (L1-L3)

Question 3

Pectineus

Answer 3

Anterior hip muscle.

• Origin: Pectineal line of the pubis.
• Insertion: Pectineal line of the femur.
• Role: Hip adduction and flexion.
• Innervation: Femoral and obturator nerve.

Question 4

Gluteus maximus

Answer 4

• Origin: Posterior surface of ilium; Sacrum, thoracolumbar
  fascia, sacrotuberous ligament.
• Insertion: Upper fibers: Gerdy’s tubercle (tibia). Lower fibers:
  Gluteal tuberosity of femur.
• Role: Hip Extension, external rotation. Upper fibers:
  abduction. Lower fibers: adduction.
• Innervation: Inferior gluteal nerve.

Question 5

Gluteus medius

Answer 5

• Origin: Posterior surface of ilium (superior 1/3)
• Insertion: Greater trochanter.
• Role: Abduction. Anterior fibers: flexion, internal rotation.
  Posterior fibers: extension, external rotation.
• Innervation: Superior gluteal nerve.

Question 6

Gluteus minimus

Answer 6

• Origin: Between anterior and inferior gluteal line of ilium.
• Insertion: Greater trochanter.
• Role: Abduction. Anterior fibers: flexion, internal rotation.
• Innervation: Superior gluteal nerve.

Question 7

Piriformis

Answer 7

Posterior hip muscle.

• Origin: Sacrum.
• Insertion: Greater trochanter.
• Role: Abduction, external rotation, internal rotation.
• Innervation: Branches of the plexus sacralis.

Question 8

Superior and inferior Gamellus

Answer 8

Posterior hip muscles.
- Origin: Superior: spine of ischium. Inferior: Ischial tuberosity.
- Insertion: Obturator internus tendon.
- Role: Hip Abduction; external rotation.
- Innervation: Superior: Lumbosacral plexus (L5, S1, S2),
Inferior: Lumbosacral plexus (L4, S1).

Question 9

Quadratus femoris

Answer 9

Posterior hip muscle.

• Origin: Ischial tuberosity.
• Insertion: Intertrochanteric crest.
• Role: Hip Adduction; external rotation.
• Innervation: Lumbosacral plexus (L4, S1).