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

1) Sides of bodies of T12-L1 vertebrae
2) Intervening IV discs
3) Transverse Processes of Lumbar Verterbrae

Question 2

Innervation of Psoas Major

Answer 2

Lumbar Plexus via anterior branches of nerves L2-L4

Question 3

Action of Psoas Major

Answer 3

Acting inferiorly with iliacus, flexes the thigh

Acting superiorly, laterally flexes the vertebral column to balance the trunk

Question 4

Origin of Iliacus

Answer 4

1) Superior 2/3 of iliac fossa
2) Ala of Sternum
3) Anterior Sacro-iliac ligament

Question 5

Insertion of Iliacus

Answer 5

1) Lesser trochanter of femur and shaft inferior to it

2) Psoas Major tendon

Question 6

Innervation of Iliacus

Answer 6

Femoral Nerve (L2-L4)

Question 7

Action of Iliacus

Answer 7

1) Flexes the thigh and supports the hip joint

2) Acts with Psoas Major

Question 8

Origin of Quadratus Lumborum

Answer 8

1) Medial 1/2 of inferior border of 12th rib

2) Tips of transverse processes of lumbar vertebrae

Question 9

Insertion of Quadratus Lumborum

Answer 9

1) Iliolumbar Ligament

2) Internal Lip of Iliac Crest

Question 10

Innervation of Quadratus Lumborum

Answer 10

Anterior Branches of T12 and L1-L4 nerves

Question 11

Action of Quadratus Lumborum

Answer 11

1) Extends and laterally flexes vertebral column

2) Fixes 12th rib during inspiration