Anatomy week 1 Flashcards
Name the 4 quadrants of the abdominal cavity
RUQ
LUQ
RLQ
LLQ
What 2 imaginary lines (vertical and horizontal) divide the abdomen into 4 quadrants
Vertical - median line
Horizontal - trans umbilical line
Name the 4 imaginary lines that divide the abdomen into 9 regions
Right and left midclavicular lines
Transtubercular line
Subcostal line
Level of transpyloric plane
L1
Name the 9 regions of the abdominal cavity
Right hypochondrium
Epigastric
Left hypochondrium
Right lumbar
Umbilical
Left lumbar
Right iliac/inguinal
Hypogastric/suprapubic
left iliac/inguinal
Name 2 structures present in the right hypochondrium
Liver (extends down to right lumbar)
Gallbladder (Extends down to right lumbar)
Name 3 structures present in the epigastric region
Liver
Stomach
Pancreas
Name 3 structures present in the left hypochondrium
Spleen
Stomach
Pancreas
Name 3 structures present in the right lumbar region
Ascending colon
Liver
Right kidney
Name 3 structures present in the umbilical region
Transverse colon
Small intestine - duodenum, jejunum, ileum
Aorta
Name 3 structures present in the left lumbar region
Descending colon
Left kidney extends down from left hypochondrium
Jejunum + ileum extends here too
Name 3 structures present in the right iliac region
Caecum
Appendix
Terminal ileum
What valve exists between the terminal ileum and caecum
Ileo-caecal valve
Name 3 structures present in the hypogastric region
Urinary bladder
Sigmoid colon
Uterus
Name 2 structures present in the left iliac region
Descending colon
Sigmoid colon
The anterolateral abdominal wall is composed of what 3 flat muscles and what 2 vertical muscles
External oblique
Internal oblique
Transversus abdominis
Rectus abdominis
Pyramidalis
2 actions and innervation (2) of external oblique
Compress + support abdominal viscera
Flex + rotate trunk
Anterior rami of T7-T12
Subcostal nerve
2 actions and innervation (3) of internal oblique
Compress + support abdominal viscera
Flex + rotate trunk
Anterior rami of T7-T12
Subcostal nerve
1st lumbar nerve
Action and innervation (3) of transversus abdominis
Compress + support abdominal viscera
Anterior rami of T7-T12
Subcostal nerve
1st lumbar nerve
3 actions and innervation of rectus abdominis
Flex trunk in lumbar region
Compress abdominal viscera
Stabilises + controls tilt of pelvis
Anterior rami of T7-T12
What artery supplies rectus abdominis
Inferior epigastric a
What muscle is superficial to the rectus abdominis and what is its function
Pyramidalis - small triangular muscle
Tenses the lines alba
What is the lines alba
Vertical fibrous white structure that runs down the midline of the abdomen from the xyphoid process to the pubic symphysis
What is the rectus sheath + what is it made up of
Fused aponeurosis of the 3 flat abdominal muscles
Aponeuroses of the external oblique, internal oblique and transversus abdominis
What is an aponeurosis
Flat sheet of tendinous tissue
How does the rectus sheath differ above and below the umbilicus
Above - internal oblique splits into 2 layers, so a layer above and below the umbilicus
Below - all 3 aponeurosis of the flat muscles pass anterior to the rectus abdominis
Order of layers pierced above the umbilicus (11)
Skin Fat External oblique fascia Anterior part of internal oblique fascia Rectus abdominis Posterior part of internal oblique fascia Transversus abdominis fascia Transversalis fascia Parietal peritoneum Peritoneal cavity Visceral peritoneum
What 2 layers is the transversals fascia found between
Transversus abdominis and parietal peritoneum
Vertebral level of umbilicus (not dermatomal level)
L3/4
dermatome is T10
What 2 landmarks is the umbilicus in the middle of vertically
Xiphoid process and pubic symphysis
What thoracic segments innervate anterior abdominal wall
Anterior rami of T7-T12
How is the inguinal canal formed during foetal development
Relocation of the gonads
Layers of the anterior abdominal wall push through the wall obliquely to form a canal
What ligament does the inguinal canal lie parallel to (and above)
Medial half of inguinal ligament
What tubercles are found in the pubic bone of the pelvis
Pubic tubercles
The inguinal ligament is attached to which 2 bony points of the pelvis (pelvic bone)
Anterior superior iliac spine
Pubic tubercle
What 3 things makes up the anterior wall of the inguinal canal
External oblique aponeurosis
Lowermost fibres of internal oblique muscle
Superficial inguinal ring
What 3 things makes up the posterior wall of the inguinal canal
Transversalis fascia
Inguinal falx (conjoint tendon)
Deep inguinal ring
What 3 things makes up the roof of the inguinal canal
Aponeurosis of internal oblique and transversus abdominis
Transversalis fascia
What makes up the floor of the inguinal canal
Inguinal ligament
What is the inguinal falx
Pubic attachments of internal oblique and transversus abdominis aponeuroses
The inguinal canal has an opening at each end - what are they and which is superior/inferior
Deep inguinal ring superiorly
Superficial inguinal ring inferiorly
Relationship of the deep inguinal ring to the inferior epigastric vessels
Ring is lateral to the inferior epigastric vessels
Relationship of superficial inguinal ring to the pubic tubercle
Superolateral to the tubercle
What muscle are the superior and inferior epigastric vessels deep to
Rectus abdominis
Superior epigastric vessels are branches of what a
Internal thoracic a
Inferior epigastric vessels are branches of what a
External iliac a
5 contents on the male inguinal canal
Spermatic cord Ductus deferens Genitofemoral nerve Ilio-Inguinal nerve Lymphatics
4 contents of the female inguinal canal
Round ligament of uterus
Genitofemoral nerve
Ilio-Inguinal nerve
Lymphatics
Which inguinal ring is the terminal end of the inguinal canal
Superficial inguinal ring
What fascia forms the deep inguinal ring
Transversalis fascia
What muscle forms the superficial inguinal ring
External oblique muscle
Inguinal hernias classified into what 2 types + which is more common
Direct and indirect
Indirect more common
Cause of indirect hernia
Congenital weakness in the deep inguinal ring, allowing abdominal contents to enter inguinal canal
Cause of direct hernia
Abdominal contents don’t herniate through the deep inguinal ring but push through a weak spot in the muscles making up the posterior wall of the inguinal canal, allowing contents to enter canal
The inguinal canal transmits what inferiorly in males
Spermatic cord
Direct hernia is medial or lateral to the inferior epigastric vessels
Medial
Indirect hernia is medial or lateral to the inferior epigastric vessels + herniates through which ring
Lateral
Deep inguinal
Does direct hernia herniate through the superficial/deep inguinal ring or something else
Pushes through weak spot in the muscles making up the posterior wall of the inguinal canal, allowing contents to enter canal and herniate out superficial ring
Femoral hernias occur below what ligament
Inguinal
What happens in a femoral hernia
Abdo contents pass into weak area at posterior wall of femoral canal medial to the inferior epigastric vessels
What are umbilical hernias + are they acquired or congenital in adults
Abdo contents pass through weakness at the umbilicus
Acquired
4 layers of the gut tube from inside to outside
Mucosa - epithelium, lamina propria, muscularis mucosae
Submucosa
Muscularis externa
Adventitia/serosa (if in abdo cavity)
3 layers of the mucosa
Epithelium
Lamina propria
Muscularis mucosae
What is the peritoneum
Transparent serous membrane that lines the abdo wall and abdo organs
One continuous layer but named differently depending of what it lines
2 subdivisions of the peritoneum
Parietal - lines the body wall
Visceral - lines organs
What are the 3 things that the peritoneum can fold to form
Mesentery
Omentum
Ligament
Where is the peritoneal cavity
Between parietal and visceral peritoneum
The abdominal cavity is divided in what 2 sacs
Greater and lesser
Through which passage does the greater and lesser sac communicate via
Epiploic foramen
Which sac is behind the stomach
Lesser sac
Where is the epiploic foramen
Posterior to the free margin of the lesser omentum
If an organ is intraperitoneal, what does it mean about its peritoneum
Completely surrounded by visceral peritoneum
If an organ is retroperitoneal, what does it mean about its peritoneum
Only covered by visceral peritoneum on the anterior surface, stuck to posterior abdominal wall
Name retroperitoneal organs/structures (SAD PUCKOR)
2nd - 4th part of duodenum Kidneys Pancreas Ascending + descending colon Adrenal gland (suprarenal gland) Ureter
Name 9 intraperitoneal organs/structures
Stomach Spleen Liver 1st part of duodenum Jejunum Ileum Caecum Transverse colon Sigmoid colon
Name an extraperitoneal organ/structure
Rectum
What does extraperitoneal mean
Structures in the abdominopelvic cavity not covered in peritoneum
Which layer of peritoneum more sensitive to pressure, pain and temp
Parietal
What is the lesser sac also known as
Omental bursa
What does the lesser omentum connect
Liver to lesser curvature of stomach
What does the greater omentum connect
Greater curvature of stomach to transverse colon
What is often referred to as the abdominal policeman + why
Greater omentum
The lower margin and right & left margins of the greater momentum are free so moves about when there’s peristaltic movements
In infection, inflammatory exudate causes the greater momentum to stick to the site of infection, therefore wrapping itself around the infected organ, thus localising the infection to a small area
What protective function does the greater momentum have
localises infection so preventing diffuse peritonitis
What is parietal peritoneum innervated by + so what does this mean for pain coming from the parietal peritoneum
T7-L1
Parietal pain is somatic so is precisely localised, extremely sensitive to stretch (Rebound tenderness)
What is visceral peritoneum innervated by + so what does this mean for pain coming from the visceral peritoneum
Autonomic nerves
Visceral pain is often referred so dull and poorly localised
Pain from the visceral peritoneum often referred to midline (i.e. pain could be coming from visceral peritoneum laterally but felt in the midline)
What actually is the greater and lesser sac
Greater sac - general space/cavity that forms the majority of the abdomen
Lesser - cavity in the abdomen posterior to the stomach and lesser omentum
Name 4 muscles of the posterior abdominal wall
Psoas major
Psoas minor
Iliacus
Quadratus lumborum
What is bilateral action of psoas major
Flexion
What vertebral level is the transtubercular line
L5 (body of L5)
Name 2 vessels stuck to the posterior abdominal wall
Abdominal aorta
IVC
Nerve plexuses in the posterior abdominal wall + other nerves
Lumbar plexus - L1-L4
Sacral plexus - L5-S4
Sympathetic trunk/chain
3 major openings in the diaphragm + the vertebral level of the opening
IVC - T8
Oesophagus - T10
Aorta - T12
3 main branches of the abdominal aorta which supple blood to gut tube
Coeliac trunk
Superior mesenteric a
Inferior mesenteric a
What vertebral level does the aorta divide into common iliac arteries
L4
What joins to form the IVC
Right and left common iliac veins
What vertebral level does the coeliac trunk branch off the aorta
T12
What vertebral level does the superior mesenteric artery branch off the aorta
L1
What vertebral level does the inferior mesenteric artery branch off the aorta
L3
After emerging from the aorta, the coeliac trunk extends approximately 1cm before dividing into what 3 major branches - 2 go left and 1 go right
Left gastric a
Splenic a
Common hepatic a
Name the structures of the foregut (3)
oesophagus, stomach, upper duodenum
Name the structures of the midgut (7)
distal part of duodenum, jejunum, ileum, caecum, appendix, ascending colon, proximal 2/3rds of the transverse colon
Name the structures of the hindgut (5)
distal 1/3rd transverse colon, descending colon, sigmoid colon, rectum and upper part of the anal canal
Arterial supply of the foregut/midgut/hindgut
Foregut - coeliac trunk
Midgut - superior mesenteric a
Hindgut - inferior mesenteric a
What 2 veins unite to form the hepatic portal vein + at what vertebral level
Superior mesenteric and splenic v
L2
Blood from the abdominopelvic GI tract drains via a what system to what organ
Portal system to the liver
What does the inferior mesenteric vein drain into
Splenic vein
What is the portal venous system
Vascular arrangement in which blood from capillaries of one organ is transported to capillaries of another organ by a vein(s)
Deoxygenated blood from GI tract and GI organs transported to liver
Blood from the gut tube superior to diaphragm or inferior to pelvic floor drains via what system + where does this system drain into
Systemic venous system
IVC carries deoxygenated blood into RA of heart
What is a portocaval/portosystemic anastomosis
Collateral communication between the portal and systemic venous system
Importance of the portocaval/portosystemic anastomosis
Provide alternative routes of circulation when there is a blockage in the liver or portal vein.
Ensures that venous blood from the GI tract still reaches the heart through the IVC without going through the liver
List 4 sites of portocaval/portosystemic anastomosis
Distal oesophagus
Anorectal junction
Paraumibilical
Retroperitoneal
Sympathetic innervation to abdominal viscera is via what 3 things
Abdominopelvic splanchnic nerves (greater, lesser and least)
Prevertebral sympathetic ganglia
Abdominal aortic plexuses
Parasympathetic innervation of abdominal viscera is via what 2 things
Vagus nerve
Pelvic splanchnic nerves (S2-S4)
Parasympathetic stimulation increases or decreases:
GI secretion
Peristalsis/motility
Increases
Sympathetic stimulation increases or decreases:
GI secretion
Peristalsis/motility
Decreases
Sympathetic stimulation of blood vessels causes what
Vasoconstriction
Parasympathetic stimulation of blood vessels causes what
Vasodilation
Effect of vagotomy (removing part of vagus nerve) on gastric secretion
Decrease rate of gastric secretion
Functional difference between greater, lesser and least splanchnic nerves (abdominopelvic splanchnic) and the pelvic splanchnic nerves
Pelvic splanchnic nerves are parasympathetic and vice versa
Arrangement of ganglia in relation spinal cord in sympathetic and parasympathetic nervous system
Sympathetic - ganglia close to spina cord as short pre-ganglionic fibre
Parasympathetic - ganglia close to target organ as long pre-ganglionic fibre
Vertebral level range of kidneys
T12 - L3
Right kidney lies slightly lower than left kidney, why?
Liver pushes down on right kidney
3 main structures entering/leaving the hilum of the kidney
Renal vein
Renal artery
Pelvis of the ureter
Anterior to posterior arrangement of the 3 tubes at the hilum of the kidney
Renal vein
Renal artery
Pelvis of the ureter
Where is the adrenal gland + what kind of gland is it
Superior to kidney
Endocrine
What is the ureter
Muscular duct carrying urine from kidneys to urinary bladder
What is the expanded upper part of the ureter called
Pelvis of ureter
Name the 3 locations that the ureter is constricted during its course from the kidney to the bladder
At the junction of the ureters and renal pelvis (pelveureteric junction)
Where it crosses external iliac artery (pelvic brim)
Just before it enters the bladder (vesico-ureteric junction)
