14. Posterior Abdominal Wall

Question 1

What are the attachments and origin of quadratus lumborum?

Answer 1

Iliac crest

To 12th rib and L1 - L4 transverse process

Question 2

What are the functions of quadratus lumborum?

Answer 2

One - bends trunk

Two - pressure/ forced expiration and support for 12th rib

Question 3

What is the nerve supply of quadratus lumborum?

Answer 3

T12 - L4 anterior rami

Question 4

What ligament under the diaphragm arches across the upper part of quadratus lumborum?

Answer 4

Lateral arcuate ligament

Question 5

What are the attachment and origin of iliacus?

Answer 5

Illiac fossa

To lesser trochanter of femur

Question 6

What is the function of iliacus?

Answer 6

Hip flexion

Question 7

What is the nerve supply of iliacus?

Answer 7

Femoral nerve

Question 8

What are the attachments and origins of psoas muscle?

Answer 8

Superficial part - T12 - L4 bodies and IV discs
Deep part - L1 - L5

Inserts - lesser trochanter of femur

Question 9

What are the functions of psoas?

Answer 9

Hip flexion

One - bend trunk laterally

Both - raise trunk from supine

Question 10

Innervation of psoas?

Answer 10

L2 - L4

Question 11

What is the name given to the tendonous fascia that arches over psoas as it passes through the diaphragm?

Answer 11

Medial arcuate ligament

Question 12

What are the right and left crus of the diaphragm?

Answer 12

Two tendonous structures that extend below the diaphragm to the vertebral column

R –> L1 - L3
L–> L1 - L2

Question 13

At what vertebral level is the aortic aperture of diaphragm?

Answer 13

T12

Question 14

At what vertebral level does the abdo aorta bifurcate into common iliac?

Answer 14

L4

Question 15

MAKE SURE YOU CAN LABEL DIAGRAM OF ARTERIES OF ABDO

Answer 15

SLIDE 11

Question 16

At what vertebral level does the common iliac vein unite to form the IVC?

Answer 16

L5

Question 17

Where does the IVC drain?

Answer 17

Right atrium

Question 18

MAKE SURE YOU CAN LABEL DIAGRAM OF VEINS OF ABDO

Answer 18

SLIDE 13

Question 19

Where do the lumbar veins drain?

Answer 19

1 + 2 - ascending lumbar
3 + 4 - IVC
5 - iliolumbar vein then common iliac

Question 20

At what vertebral level do the gonadal arteries branch from the abdo aorta?

Answer 20

L2

Question 21

Into which veins do the gonadal veins drain?

Answer 21

R –> IVC

L –> left renal

Question 22

What are the named nerves of the lumbar plexus? (6)

Answer 22

Iliohypogastric
Ilioinguinal
Genitofemoral
Lateral femoral cutaneous
Obturator 
Femoral

Question 23

Nerve roots of iliohypogastric?

Answer 23

L1

Question 24

What does iliohypogastric nerve supply?

Answer 24

Sensory - lateral gluteal skin and pubic skin

Motor - internal oblique and transversus abdominis

Question 25

Nerve roots of ilioinguinal?

Answer 25

L1

Question 26

What does ilioinguinal nerve supply?

Answer 26

Sensory - skin of medial thigh and root of penis/ scrotum or mons pubis/ labium major

Motor - internal oblique and transversus abdominis

Question 27

Nerve roots of genitofemoral?

Answer 27

L1 and L2

Question 28

What does genitofemoral nerve supply?

Answer 28

Sensory - scrotum or mons pubis and skin of upper anterior thigh

Motor - cremasteric muscle

Question 29

Nerve roots of lateral cutaneous nerve of thigh?

Answer 29

L2 and L3

Question 30

What does lateral cutaneous nerve of thigh supply?

Answer 30

Sensory - skin of anterior and lateral thigh

Question 31

Nerve roots of femoral nerve?

Answer 31

L2 - L4

Question 32

What does femoral nerve supply?

Answer 32

Sensory - skin of anterior thigh and medial leg

Motor - pectineus, iliacus and anterior compartment of thigh

Question 33

Nerve roots of obturator nerve?

Answer 33

L2 - L4

Question 34

What does obturator nerve supply?

Answer 34

Sensory - skin on medial thigh

Motor - obturator externus and medial compartment of thigh