Posterior Abdominal Wall

Front 1

name and identify the muscles forming the posterior abdominal wall

Back 1

• The principal muscles of the posterior abdominal wall are the aponeurosis of transversus abdominis,
quadratus lumborum, iliacus and psoas (major & minor).

Front 2

name the major branches of the abdominal aorta

Back 2

A. Unpaired brs to viscera (supply GIT): coeliac trunk, superior mesenteric a., inferior mesenteric a.
B. Paired brs to viscera: middle suprarenal, renal, gonadal (ovarian/ testicular)
C. Brs to body wall: inferior phrenic, lumbar brs (4 pairs), median sacral (unpaired)

Front 3

the collateral circulation between the IVC and SVC and the effects of a blockage of either

Back 3

1. Anastomosis of superficial veins on trunk wall
2. Azygos & hemiazygos
3. Lumbar and ascending lumbar vv
4. Portal vein

Front 4

Posterior abdominal wall cf to anterior

Back 4

Posterior abdominal wall
- less extensive than anterior wall
- more protected by bone

Front 5

Paravertebral Gutters

Back 5

The abdominal cavity is kidney-shaped in cross section
The lumbar vertebral bodies project forward, creating gutters on each
side – the paravertebral gutters
Organs such as the kidneys, ascending & descending colon lie in the
paravertebral gutters
The abdominal aorta & IVC lie anterior to the vertebral bodies and are
closer than expected to the anterior abdominal wall, especially just
above the umbilicus

Front 6

Clinically Psoas Sign

Back 6

Iliopsoas flexes hip but is also part of the posterior abdominal wall
Lower abdominal pathology may result in a positive psoas sign (pain on active flexion)
Causes include an appendicitis or a retroperitoneal haemorrhage

Front 7

Major Tribuitaries of IVC

Back 7

Inferior Vena Cava lies to the right side of abdominal aorta
Major tributaries are the hepatic veins, the renal veins, the suprarenal veins, the lumbar veins and the gonadal veins

Front 8

Abdominal Aorta
- AAA

Back 8

• The abdominal aorta starts at T12 and ends at L4.

Front 9

Lymph Nodes

Back 9

Unpaired viscera (GI tract) drain  preaortic nodes
Other structures below diaphragm drain para-aortic nodes (lower limbs, pelvis, posterior abdominal wall, paired viscera)
Pre and para-aortic nodes drain to cysterna chyli  forms thoracic duct
Thoracic duct  drains to junction of left subclavian & left internal jugular veins

Front 10

Pre- arotic

Back 10

infront of aorta
- thus recieve lymph from the GI tract because the blood to the guts comes from here

Front 11

Virchows Node

Back 11

Virchow’s node
Left supraclavicular lymph node near termination of thoracic duct
Part of the deep cervical nodes
Enlargement may be a signal of lymph spread of a tumour from the
area of drainage of the thoracic duct
For example, may indicate cancer of lung, stomach, intestine, testis

Front 12

Lymphatic Drainage of the Body

Back 12

Front 13

Nerves of posterior Abdominal Wall

Back 13

Somatic nerves to the abdominal wall and inguinal region include the subcostal, iliohypogastric, ilioinguinal
and genitofemoral nerves.

Front 14

Autonomic Nerves

Back 14

• Sympathetic autonomic nerves are the thoracic, lumbar and sacral splanchnics.
• Para-sympathetic autonomic nerves are the vagal trunks and the pelvic splanchnics.

Front 15

IVC starts at

Back 15

• The IVC lies to the right of the aorta and starts at L5 and ends at T8.

Front 16

Retroperitoneal Structures

Back 16

Retroperitoneal structures (structures posterior to peritoneum) include:
suprarenal glands, kidneys, ureters, pancreas (except tail), duodenum (except first few cms), ascending &
descending colon, abdominal aorta, IVC & all associated lymph nodes and autonomic nerves

Front 17

Clinical Significance

Back 17

clincal significance; T12-L1, thus can get back pain from inflammation of these structures irritating the somatic nerves

Front 18

Retroperitoneal Structures

Back 18

Front 19

Suprarenal Glands:
aa
vv
nn

Back 19

Arterial supply: superior, middle and inferior suprarenal (branches of inferior phrenic, abdominal aorta & renal arteries, respectively)
Venous drainage: right suprarenal gland drains to IVC, left suprarenal gland drains to left renal vein
Innervation: preganglionic sympathetic nerves from the thoracic splanchnic nerves synapse directly on chromaffin cells
of adrenal medulla (not via postganglionic neurons). Cells release adrenaline & noradrenaline directly into the circulation via suprarenal veins

Front 20

Suprarenal Glands

Back 20

Front 21

Suprarenal Glands Innervation

Back 21

Front 22

Back 22

A. renal outline, B. gas in fundus of stomach, C. sacroiliac joint, D. gas in ascending colon, E. faeces in
ascending colon, F. gas in rectum or sigmoid colon, G. lateral border of psoas major, H. gas in transverse colon