Posterior Abdominal Wall

Question 1

What is the description of fascia

Answer 1

A continuous layer of connective tissue between peritoneum and muscle

Question 2

What forms the rectus sheath

Answer 2

The aponeuroses of the transverse abdominal and the internal and external oblique muscles

Question 3

What is the arcuate line of the rectus sheath

Answer 3

Horizontal line demonstrating the lower limit of the posterior layer of the rectus sheath

Question 4

Name the three paired muscles of the posterior abdominal wall

Answer 4

1. Quadratus lumborum
2. Iliacus
3. Psoas major

Question 5

Where does the quadratus lumborum muscle travel from, and to

Answer 5

The iliac crest to the 12th rib and the transverse processes of L1-L4

Question 6

What is the innervation of the quadratus lumborum muscle

Answer 6

Anterior rami of T12-L4

Question 7

What is the function of the quadratus lumborum muscle

Answer 7

One = Bends trunk to the same side
Both = Pressure, forced expiration and support for the 12th rib

Question 8

Where does the iliacus muscle travel from, and to

Answer 8

The iliac fossa into the lesser trochanter of the femur (with the psoas; as the iliopsoas)

Question 9

What is the innervation of the iliacus muscle

Answer 9

Femoral nerve

Question 10

What is the functions of the iliacus muscle

Answer 10

Hip flexion

Question 11

Where does the psoas major muscle travel from, and to

Answer 11

T12-L4 vertebrae (superficial) and L1-L5 vertebrae (deep) to the lesser trochanter of the femur (with the iliacus; as the iliopsoas)

Question 12

What is the innervation of the psoas major muscle

Answer 12

Lumbar plexus direct branches L2-L4

Question 13

What is the function of the psoas major muscle

Answer 13

One = Hip flexion and bends trunk laterally
Both = Raises trunk from supine position (during sit ups)

Question 14

What is the psoas minor

Answer 14

A long tendon lying anterior to the psoas major muscle

Question 15

Where does the thoracic aorta pierce the diaphragm

Answer 15

The aortic hiatus at T12, where it becomes the abdominal aorta

Question 16

What are the common branches of the abdominal aorta

Answer 16

1. Inferior phrenic to diaphragm
2. Lumbar and median sacral to abdominal wall
3. Abdominal viscera, kidneys, ovaries/testes

Question 17

Where are the common iliacs formed

Answer 17

Abdominal aorta bifurcates at L4

Question 18

Where is the IVC formed

Answer 18

At L5, where the common iliac veins unite

Question 19

How does blood from the gut enter the IVC

Answer 19

Through the hepatic veins from the liver

Question 20

What lumbar veins tend to drain directly into the IVC

Answer 20

Lumbar veins 3 and 4

Question 21

Where does the 5th lumbar vein tend to drain into

Answer 21

The iliolumbar vein; and then into the common iliac vein

Question 22

Where does the ascending lumbar vein travel to

Answer 22

Travels superiorly where it communicates with the azygous and hemi-azygous veins

Question 23

What lumbar veins tend to drain into the ascending lumbar vein

Answer 23

Lumbar veins 1 and 2

Question 24

Where do the gonadal vessels branch from the abdominal aorta

Answer 24

At L2

Question 25

What is the innervation of the posterior abdominal wall

Answer 25

Sympathetic innervation from T1-L1/L2

Question 26

What do autonomic fibres form within the abdomen

Answer 26

Plexuses using fibres from the sympathetic chains around the anterior portion of the aorta

Question 27

What nerve supplies the parasympathetic innervation of the foregut and midgut

Answer 27

Vagus nerve; cranial nerve X

Question 28

What nerves supplies the parasympathetic innervation of the midgut

Answer 28

Pelvis splanchnic nerves; S1-S4

Question 29

What nodes does lymph from the pelvis travel to

Answer 29

Iliac nodes

Question 30

What nodes does lymph from the body wall, kidneys and testes/ovaries travel to

Answer 30

Para-aortic (lateral) nodes

Question 31

What nodes does lymph from the digestive tract travel to

Answer 31

Pre-aortic nodes

Question 32

Where does the thoracic duct begin

Answer 32

At the cisterna chyli, at L1/L2

Question 33

What is the innervation of the lumbar plexus

Answer 33

Anterior rami of L1-L4

Question 34

What are the 6 nerves of the lumbar plexus

Answer 34

1. Iliohypogastric
2. Ilioinguinal
3. Genitofemoral
4. Lateral femoral cutaneous
5. Obturator
   6 Femoral

Question 35

What is the root value of the iliohypogastric and ilioinguinal nerves

Answer 35

Anterior rami L1

Question 36

What information does the iliohypogastric nerve supply

Answer 36

Sensory = Lateral gluteal and pubic skin 
Motor = Internal oblique and transversus abdominis

Question 37

What information does the ilioinguinal nerve supply

Answer 37

Sensory = Skin on medial thigh and the scrotum/penis or mons pubis/labia majora
Motor = Internal oblique and transversus abdominis

Question 38

What is the root value of the genitofemoral nerve

Answer 38

Anterior rami L1-L2

Question 39

What information does the genitofermoral nerve supply

Answer 39

Sensory = Scrotum or mons pubis and skin of the upper anterior thigh
Motor = Cremasteric muscle

Question 40

What is the root value of the lateral cutaneous femoral nerve

Answer 40

Anterior rami of L2-:3

Question 41

What information does the lateral cutaneous femoral nerve supply

Answer 41

Sensory = Skin on the anterior and lateral thigh

Question 42

What is the root value of the obturator nerve

Answer 42

L2-L4

Question 43

What information does the obturator nerve supply

Answer 43

Sensory = Skin on medial thigh
Motor = Obturator externus and medial compartment of thigh

Question 44

What is the root value of the femoral nerve

Answer 44

L2-L4

Question 45

What information does the femoral nerve supply

Answer 45

Sensory = Anterior thigh and lateral leg
Motor = Pectineus and iliacus muscles, and the anterior compartment of the thigh