Class 2 Flashcards
Subdivisions of the peritoneum?
Visceral and parietal
Define the peritoneal cavity?
Potential space between the parietal and visceral peritoneum
What are the 2 sacs of the peritoneal cavity?
The great and lesser sac (Omental bursa)
They communicate through the epiploic foramen
What layer of peritoneum is sensitive to pain?
Parietal because its supplied by the same somatic nerve as the adjacent section of abdominal wall
Define extraperitoneal?
Structures in abdominopelvic cavity not covered in peritoneum
What does partially peritonised mean?
The structure is not directly covered in peritoenum e.g. the kidneys which are rested on by other retroperitoneal organs
Explain the greater and lesser omenta?
Greater - Greater curvature of stomach to transverse colon
Lesser - Lesser curvature of stomach to the liver (specifically the porta hepatis)
Why do we call the greater omentum the abdominal policemen?
Its lower and left/right margins are free so it moves about in response to peristalsis.
In infection, inflammatory exudate causes the omentum to adhere to the site of infection and wrap around the infected organ
Explain the innervation of the two peritoneal layers
PArietal - Lower 6 thoracic and L1 spinal nerves
Visceral - Autonomic nerves so pain is referred, dull and poorly localized, the pain is often referred to the midline due to the bilateral nerve supply.
What are the muscles of the posterior abdominal wall?
Quadratus lumborum
Psoas major + minor
Iliacus
What vessels and nerves are present on the posterior abdominal wall?
Aorta
IVC
Femoral nerve (comes down from behind psoas major laterally) Obturator Nerve (Comes down from inside of psoas and innervates leg adductors)
Adduction vs abduction?
Adduction - Towards bodies midline
Abduction - Away from midline
Attachment of psoas major and function
Immediately lateral to the lumbar vertebrae.
Attaches to transverse processes/vertebral bodies of T12-L5, runs down and joins with iliacus to form iliopsoas then attach to lesser trochanter of femur
Flexes the thigh & Lateral flexion of the lumbar spine
Attachment of quadratus lumborum and function?
Thick muscular sheet quadrilateral in shape.
Superficial to the psoas major.
Originates from iliac crest and iliolumbar ligament. Travels superomedially, inserts onto transverse processes of L1-4 and inferior border of the 12th rib
Extension and lateral flexion of the vertebral column. It also fixes the 12th rib during inspiration, so that the contraction of diaphragm is not wasted.
Attachment and function of the iliacus?
Fan shaped muscle inferior on posterior abdominal wall combines with psoas major to form the iliopsoas – the major flexor of the thigh.
Surface of iliac fossa and anterior inferior iliac spine. Its fibres combine with the tendon of the psoas major, inserting into the lesser trochanter of the femur.
Actions: Flexion of the thigh at the hip joint.
Level of 3 major diaphragmatic opening?
T8 Caval opening
T10 Gastric Hiatus
T12 Aortic Hiatus
Organs of posterior abdominal wall?
Kidneys
Ureters
Supradrenal glands
At what level does the abdominal aorta divide?
L4 –> 2 Common Iliac Arteries
Whereas the veins form into the IVC at L5
Main branches of abdominal aorta?
Celiac Trunk (T12)
Sup. Mesenteric art (L1)
Inf. Mesenteric art (L3)
Where is the boundary of the fore/mid/hind gut?
Fore/midgut = Between the 2/3rd section of duodenum
Mid/hindgut = 2/3rd of the way along transverse colon
What vessels arise from the celiac trunk?
The Gastric art.
Splenic Art.
Hepatic Art.
Define a portal system?
A vein connects one capillary bed to another
What 2 major veins form the hepatic portal vein?
Splenic and sup. mesenteric
but also the gastric and inf. mesenteric
List the 4 porto-systemic anastomoses and their pathology
Gastroesophageal junction
Anorectal juncction
Umbilicus (paraumbilical veins)
Intrahepatic
During portal hypertension they become distended, known as varices. Which are painful and can bleed
Sympathetic nerve supply to the abdominal viscera?
Abdominopelvic splanchnic nerves (T7-L2)
- Thoracic Splanchnic Nerves (T7-T12)
- Lumbar Splanchnic Nerves (L1-L2)
Prevertebral sympathetic ganglia
Abdominal Aortic Plexuses
Parasympathetic nerve supply to abdominal viscera?
Anterior & Posterior vagal trunks (i.e. vagus nerve)
Pelvic splanchnic nerves (S2-4)
What is the effect of a vagotomy on gastric secretion?
Decreases it
Functional difference between thoracic and pelvic splanchnic nerves?
Greater, lesser, least splanchnic nerves are sympathetic
Pelvic splanchnic nerves are parasympathetic
Arrangement of ganglia in the symp. vs parasymp. systems?
Sympathetic = Paravertebral ganglia Parasympathetic = Prevertebral ganglia (lie in or near the organs they supply)
At what vertebral level do the kidneys lie?
On posterior abdominal wall at T12-L3 vertebrae
Why does the right kidney lie slightly lower?
Liver
arrangement of vessels at kidney hilum?
Anterior to posterior
Vein - Artery - Pelvis of Ureter (VAP)
The artery is also superior.
Location and type of gland is suprarenal?
Superior to the kidneys
Endocrine
What is the pelvis of the ureter?
The expanded section where it enters the kidney.
The ureters are muscular ducts carrying urine from kidney to bladder
Where are the 3 constrictions of the ureter?
Pelviureteric junction (between ureter and renal pelvis)
As it enters pelvis and crosses the common iliac artery bifurcation
Vesicouretic junction (ureter enters the bladder wall)
How are the ureters peritonised?
Retroperitoneal
What organs fall into each of the 9 abdominal sections?
R. Hypochondriac = Liver
Epigastrium = Stomach - Pancreas
L. Hypochondriac = Stomach - Spleen
R. Lumbar = Small intestine - Asc. Colon
Umbilicus = Small Intestine - Transverse Colon - Gall Bladder
L. Lumbar = Small Intestine - Desc. Colon
R. Iliac Fossa = Asc. Colon - Caecum
Hypogastrium = Sigmoid colon - Small intestine
L. Iliac Fossa = Sigmoid Colon - Desc. Colon
