1. Posterior Abdominal Wall Muscles

Question 1

Psoas Major origin + insertion

Answer 1

Origin:
Lateral surface T12-L5 vertebral bodies, transverse processes and IV discs

Insertion:
Lesser Trochanter of femur

Question 2

Psoas Major Innervation

Answer 2

Anterior Branch or L1 - L3

Question 3

Psoas Major action

Answer 3

Hip Flexion
External Rotation
Lateral Flexion of Trunk

Question 4

Psoas Minor origin + insertion

Answer 4

Origin
- lateral surface T12-L1 vertebral bodies and IV discs

Insertion
- pectineal line of pelvis (aka pectin pubis)

Question 5

Psoas Minor Innervation

Answer 5

anterior branch of L1

Question 6

psoas minor action

Answer 6

weak flexion of lumbar vertebral column

Question 7

Iliacus origin + insertion

Answer 7

origin:

• upper 2/3 of iliac fossa
• illiolumbar and anterior sacroiliac ligaments
• upper antero-lateral surface of sacrum

insertion:
- lesser trochanter of femur

Question 8

Iliacus innervation

Answer 8

femoral nerve (L2-L4)

Question 9

Iliacus action

Answer 9

hip flexion, stabilization

acts w psoas mj

Question 10

Quadratus Lumborum origin + insertion

Answer 10

origin

• transverse processes of lumbar vertebrae
• iliac crest

insertion
- inferior border of rib 12

Question 11

Quadratus Lumborum innervation

Answer 11

anterior branch of T12 and L1-4

Question 12

Quadratus Lumborum action

Answer 12

extension and lateral flexion of vertebral column

Question 13

which of these muscles is not always present?

Answer 13

psoas minor

- 50%

Question 14

nerve that pierces psoas major

Answer 14

genitofemoral nerve