Posterior abdominal wall Flashcards
- Describe the bones and muscles that compose the posterior abdominal wall. - Describe the hiatuses within the diaphragm and the structures that pass through. - Describe the iliopsoas muscle. - Describe the course of the abdominal aorta and its main branches. - Describe the relationship of the abdominopelvic veins with respect to arteries. - Describe the relationship of the inferior vena cava to the aorta. - Describe the nerves supplying the abdominal walls. - Gain a basic knowledg
Bones of the posterior abdominal wall
Ribs XI and XII
Sacrum
Ilia
Lumbar vertebrae
Diaphragm
- Origin
- Insertion
- Action
- Haitus
Origin:
- Xiphoid process
- Inferior 6 ribs
- Crura and arcuate ligaments (lumbar)
Insertion:
Central tendon
Action:
- Increases/decreases volume of thoracic and abdominal cavity
- Central tendon prevents constriction of vessels at hiatus.
Hiatuses:
- T8= IVC
- T10= oesophagus
- T12= aorta
Quadratus lumborum
- Origin
- Insertion
- Action
Origin:
- Iliac crest
- Transverse process of LV
Insertion:
- Inferior border of rib XII
- Transverse process of LI to LIV
Action:
- Lateral flexion of the trunk
- Stabilises rib XII
Illiacus
- Origin
- Insertion
- Action
Origin:
- Iliac fossa
- Upper lateral surface of sacrum
Insertion:
- Lesser trochanter of the femur
Action:
- Flexion of thigh at the hip
Psoas major
- Origin
- Insertion
- Action
Origin:
- Lateral surface of TXII and Lumbar vertebrae
Insertion:
- Lesser trochanter of the femur
Function:
- Flexion of the thigh at the hip
Blood supply of the diaphragm
Superior and inferior phrenic arteries and veins
Blood supply the quadratus lumborum
Lumbar arteries and veins
Blood supply of the psoas major
Lumbar branch of iliolumbar artery.
Innervation of diaphragm
Phrenic nerve - C3-5
- All motor supply and sensory supply of central area
Intercostal and subcostal nerve supply the sensory nerves for the rest
Branches of the abdominal aorta
Paired lumbar at each vertebrae level
At T12:
Coeliac trunk
Middle suprarenal
L1:
Superior mesenteric
L2:
Renal arteries
Gonadal (paired)
L3:
Inferior mesenteric
L5:
Right and left common iliac
Branches of the inferior vena cava
L1:
- Right suprarenal
- Right and left renal
L2:
Right gonadal
L5:
Right and left common iliac
Abdominal aortic aneurysm
Ballooning of vessel
- More common below renal arteries
Usually caused by atherosclerosis weakening the wall overtime
Claudication
Pain in the leg caused by occlusion at the aortic bifurcation
Consequence:
- Impotence in males
Somatic nerves of the abdomen
- Nerves
- Control
- Innervation
Lumbar plexus L1-4
- Gives motor and sensory supply
Allows voluntary muscle control and sensation.
Innervates:
- Muscles of the anterior and posterior abdominal wall.
- Joints
- Skin
Sympathetic supply of the abdomen
Segmented structures like blood vessels in muscle and sweat glands:
- Sympathetic chain
Viscera:
- Celiac, superior and inferior mesenteric ganglion
- pre vertebral ganglia: nerves from spinal cord that bypass sympathetic chain to synapse at viscera.
Parasympathetic supply of the abdomen
Vagus nerve [CNX]:
- Foregut and midgut
Pelvic splanchnic [S2-4]:
- Hindgut
Celiac ganglion
Collection of cell bodies around coeliac trunk- pre-vertebral ganglion
Fibers from sympathetic fibers Greater splanchnic nerves [T5-9] synapse here
Supplies the foregut
Superior mesenteric ganglion
Collection of cell bodies around superior mesenteric artery: pre-vertebral ganglion
Fibers from the lesser splanchnic nerves [T10-11] synapse here.
Inferior mesenteric ganglion
Collection of cell bodies around inferior mesenteric artery: pre-vertebral ganglion
Aorticorenal ganglion
Collection of cell bodies where the lesser splanchnic nerve [T10-11] synpases at.
Supplies the kidneys and upper ureter
Kidney nervous supply
Mainly supplied by the least splanchnic nerve [T12]
Least splanchnic nerve synapses at renal plexus.
Innervation of adrenal glands
Innervated by the greater, lesser and least splanchnic nerves:
Synapse at celiac and aorticorenal ganglia
Somatic abdominal pain
Arises from: Skin Fascia Muscle Parietal peritoneum
This pain is localised and severe
Visceral abdominal pain
Pain that arises from:
- Abdominal organs
- Mesentery
- Visceral peritoneum
Caused by:
- Stretching of mesentery or viscera
- Impaired blood supply to viscus
- Chemical damage to viscus
Type of pain:
- Dull
- Poorly localised
- Midline
Referred abdominal pain
When pain is felt at a location other than the site of origin
- Due to being supplied by the same/ adjacent segments of the spinal cord
Pain is produced by somatic or visceral structures
Stomach referred pain
T5-9
Appendix referred pain
T10
Gallbladder referred pain
T7-9
Parietal peritoneum at C3-4
Central diaphragm referred pain
C3-5
Parietal diaphragm referred pain
T7-11
Anterior abdominal wall referred pain
T7-12, L1
Psoas major innervation
Femoral (L2-L4)
