Main Muscles of the Posterior Abdominal Wall

Question 0

Insertion of Psoas Major

Answer 0

Strong tendon to Lesser Trochanter of Femur

Question 1

Origin of Psoas Major

Answer 1

Transverse processes of Lumbar vertebra

Sides of bodies of T12-S1 vertebra and intervening IV discs

Question 2

Innervation of Psoas Major

Answer 2

Lumbar Plexus via Anterior branches of nerves L2-L4

Question 3

Actions of Psoas Major

Answer 3

Acting inferiorly with Iliacus, flexes thigh
Acting superiorly, flexes vertebra column laterally to balance the trunk
When sitting, acts inferiorly with Iliacus to Flex trunk

Question 4

Origin of Iliacus

Answer 4

Superior two thirds of Iliac Fossa
Ala of Sacrum
Anterior Sacro-iliac Ligaments

Question 5

Insertion of Iliacus

Answer 5

Lesser Trochanter of Femur
Shaft Inferior to it
Psoas Major Tendon

Question 6

Innervation of Iliacus

Answer 6

Femoral Nerve L2-L4

Question 7

Actions of Iliacus

Answer 7

Flexes thigh and stabilizes hip joint

Acts with Psoas Major

Question 8

Origin of Quadratus Lumborum

Answer 8

Medial half of Inferior border of 12th Rib

Tips of Lumbar Transverse Processes

Question 9

Insertion of Quadratus Lumborum

Answer 9

Iliolumbar Ligament

Internal Lip of Iliac Crest

Question 10

Innervation of Quadratus Lumborum

Answer 10

Anterior branches of T12

L1-L4 nerves

Question 11

Actions of Quadratus Lumborum

Answer 11

Extends and Laterally Flexes vertebral column

Flexes 12th rib during Inspiration