abdomen Flashcards
how is the abdomen divided into quadrants
line horizontally and vertically through umbilicus
what are the borders of the abdomen ?
superior: costal margin
inferior: pubic symphysis and inguinal ligaments
lateral: iliac crests and skin
what planes divide the abdomen into 9 regions
transpyloric plane - level with where 9th costal cartilage and midclavicular line meet
intertubecular plane - line between superior aspects of iliac crests (where the iliac tubercles lie)
mid clavicular lines
where is the subcostal plane and what vertebral level is it level with?
inferior border of costal margin and L3 (quite low down!)
what spinal level is the intertubercular plane level with?
L5 (and iliac tubercles)
what are the 2 superficial layers of the anterior abdominal wall
what is the significance of the arcuate line?
above this - the rectus sheath is anterior and posterior to the rectus abdominis
below, all anterior
what is the rectus sheath?
aponeurosis of the flat muscles of the anterior abdominal wall
what is the linea alba ?
aponeurosis of flat muscles intertwined in midline - attaches from xiphisternum to PS
what are the attachments of rectus abdominis?
xiphisternum, costal cartilage 5-7, pubic crest and symphysis
what innervates rectus abdominis?
thoracabdominal neves T7-11
where does EO attach?
5th-12th rib
linea alba
iliac crest
pubic tubercle
what are the actions of EO and IO ?
rotation of trunk - contralateral to each other
what are the attachments of IO ?
10-12 rib thoracolumbar fascia Linea alba iliac crest pubic symphysis via conjoint tendon
what are the attachments of transversus abdominis ?
rib 7-12 linea alba thoracolumbar fascia iliac crest pubic crest and conjoint tendon
what innervates IO and TA
iliohypogastric and ilioinguinal nerves
thoracoabdominal nerves T7-12
above the acruate line, what aponeurosis can be found anterior/posterior to rectus abdominis?
TA posterior
IO - posterior and anterior (splits)
EO - anterior
below the arcuate line, what aponeurosis can be found anterior/posterior to the rectus abdominis?
all anterior
what is the deepest layer of the anterior abdo wall?
parietal peritoneum
where is the inguinal canal?
canal through the anterior abdominal wall parallel and superior to inguinal ligament
what are the borders of the inguinal canal?
superior: IO and TA
posterior: transversalis fascia
inferior: inguinal ligament
anterior: EO
identify the superficial inguinal ring
where is the deep inguinal ring?
transversalis fascia at midpoint of inguinal ligament lateral to inferior epigastric vessels
compare the formation of the inguinal canal in males and females
both formed due to the presence of the gubernaculum attaching the gonad to the genital swellings
in females, the ovaries are pulled down into the pelvis then stop hence the remnant of the gubernaculum, the round ligament, passes through the inguinal canal
in males, the teste is pulled all the way through the inguinal canal to the scrotum so the spermatic cord (attaches to the teste) passes through the inguinal canal
in both the male and female, the genital branch of the genitofemoral passes through the canal, and the ilioinguinal nerve enters the canal through the posterior wall/roof and exist via the superficial inguinal ring (doesn’t pass through the deep ring)
what is hesselbachs triangle?
triangle where direct inguinal hernias pass through
image is a view from internally
describe the peritoneum
continues membrane
divided into two layers based on what the membrane is in contact with
parietal - on inner surface of anterior abdominal wall
visceral - in contact with the intraperitoneal abdominal organs
describe the nerve supply of the peritoneum
takes nerve supply of what it is in contact with
visceral - splanchnics
parietal - somatic
what is a mesentery
double fold of visceral peritoneum connecting intra-abdominal organ to posterior abdo wall
what is a difference in the structure of the greater and lesser omenta?
greater - 4 layers of visceral peritoneum
lesser - 2 layers of visceral peritoneum
what layer of peritoneum covers the retroperitoneum organs?
parietal
what is the lesser omentum also known as?
hepatogastric and hepatoduodenal ligament
where is the epiploic foramen (aka foramen of windslow)
foramen between the lesser and greater sac - hepatoduodenal ligament formes opening of this
where is the greater omentum attached to?
greater curve of stomach, proximal duodenum and transverse colon
where does the portal triad run within the lesser omentum
free edge of hepatoduodenal ligament
where would the pancreas be on this image?
pancreas tail is within the splenorenal ligament which is formed from dorsal mesentery of the foregut
we can see how the pancreas is secondarily retroperitoneal here
where doe the liver and spleen develop in relation to the stomach?
liver - ventral mesentry
spleen - dorsal
what is the falciform ligament a remnant of?
anterior attachment of ventral mesentry of stomach
double fold of parietal peritoneum
what organs are intraperitoneal?
stomach, liver, spleen, gall bladder, jejunum, ileum, caecum, transverse colon, sigmoid colon
what organs are secondarily retroperitoneal?
duodenum, pancreas, ascending and descending colon
what structures and organs are primarily retroperitoneal?
oesophagus, kidneys, ureters, rectum adrenal glands, aorta, IVC
what are the boundaries of the foregut?
oesophagus to 2nd part (descending part) of duodenum
what are the boundaries of the midgut?
2nd part of duodenum to 2/3rds legnth of transverse colon
what are the boundaries of the hindgut?
distal 1/3rd of transverse colon to anal canal
describe the attachment of the small bowel mesentery to the posterior abdominal wall
from left hypochondrium to right iliac fossa
what arteries supply the foregut, midgut and hindgut?
CT, SMA, IMA
where does the coeliac trunk branch from the abdominal aorta ?
T12 - immediately after aortic hiatus
what are the branches of the CT?
left gastric, common hepatic and splenic
what does the common hepatic artery branch into?
proper hepatic - liver
gastroduodenal
what does the left gastric artery supply?
lesser curve stomach and abdominal oesophagus
what does the splenic artery supply?
spleen, pancreas, fundus of stomach, greater omentum
what are the branches of the SMA ?
jejunal, ileal, ileocolic, right colic, middle colic
compare the mesentery of the ilium and jejunum
jejunum: less fat, longer vasa recta, fewer arterial arcades
ileum: more fat, more arterial arcades, shorter vasa recta
what are the branches of the IMA
left colic, sigmoid and superior rectal
where does the SMA branch
L1 - transpyloric plane
branches and over the left renal vein
where does the IMA branch
subcostal plane - L3
what is the missing label?
major duodenal papilla - where ampulla of vater drains into duodenum - controlled by sphincter of oddi
where does the SMA pass in relation to the duodenum?
SMA anterior to inferior part of duodenum
what ligament marks the duodenal-jejunal junction?
ligament of treitz
how can you differentiate the jejunum from the duodenum?
mesentery
describe the blood supply to the duodenum. why is this significant?
Proximal to the major duodenal papilla – supplied by the gastroduodenal artery (branch of the common hepatic artery from the coeliac trunk).
Distal to the major duodenal papilla – supplied by the inferior pancreaticoduodenal artery (branch of superior mesenteric artery).
marks the junction between foregut and midgut derivatives
describe the wall of the jejunum and ileum
plicae circularis (circular bands of muscle)
more in the jejunum and less in ileum
what is a unique feature of large bowel?
appendicies epiploicae
teniae coli - these 3 longitudinal bands of muscle contract forming sacculations known as haustra
where are payers patches found
wall of terminal ileum
where do the 3 bands of taenia coalesce
appendix
label the stomach
describe the right and left gastric artery
right - from proper hepatic
left - from CT
anastamose to form an arcade running on the lesser curve
describe the left and right gastroepiploic artery
left branches from the splenic
right branches from the gastroduodenal artery
anastomose forming arcade on greater curve
what are the 3 layers of muscle in the stomach?
longitudinal
circular
oblique
describe the venous drainage of the stomach
left and right gastric vein into hepatic portal vein
left and right gastroepiploic into SMV/splenic vein
where does the IMV drain into?
splenic vein
describe the anatomical location of the spleen
anterior to ribs 9-11
posterior to stomach and splenic flexure of colon
lateral and superior to kidney
how can you orientate a spleen?
notch on superior border
describe the impressions of the spleen
renal, gastric, colic
describe the anatomy of the pancreas
head neck uncinate process body tail
what 2 arteries supply branches to the pancreas?
gastroduodenal and splenic (see workbook)
what separates the pancreas from the stomach?
lesser sac
where is the transverse mesocolon on relation to the pancreas?
attaches to the anterior pancreas as this is secondarily retroperitoneal
where does the sma emerge relative to the pancreas?
posterior/inferior to the neck of the pancreas
anterior to uncinate process
descrive the venous drainage of the pancreas?
pancreatic veins drain neck, body and tail of pancreas into splenic vein
head drained by SMV/portal vein
where is the liver?
right hypochondrium mainly
partly left hypochondrium
what are the 2 surfaces of the liver?
diaphragmatic (superior anterior) and visceral (posterior-inferior)
what holds the liver in place?
IVC (via hepatic veins and connective tissue)
Falciform ligament
coronary and triangular ligaments
hepatoduodenal and hepatogastric ligaments (lesser omentum)
Where are the coronary and triangular ligaments found
superior surface of liver (part of diaphramatic surface)
label this diagram
locate the lobes of the liver, as well as the ligamentum venosum and ligamentum teres
ligamentum venosum and teres are continuous
where is glissons capsule ? describe its innervation
deep to visceral peritoneum covering the liver
extends into the liver over the vasculature
innervated by intercostal nerves (somatic) so when stretched - sharp and localised pain
describe the blood supply of the liver
CT -> common hepatic -> proper hepatic -> left and right hepatic
hepatic portal vein
describe the pathway for bile from the liver
bile duct joins with cystic duct to form common bile duct, with drains into the duodenum via the ampulla of vata (never acctually joins with pancreatic duct as the enzymes in the pancreatic duct would erode the CBD)
where does the cystic artery arise from?
right hepatic artery
describe a liver lobule
central vein
arteriole (from proper hepatic artery)
venule (from portal vein)
bile ductule (drains to bile duct)
describe the areas of the gall bladder
where do the cystic veins drain into?
portal vein
describe the location of the gall bladder
lies on inferior border
fundus is most anterior lateral
neck more medial and posterior
where do the kidneys sit?
T11 left T12 right (lower due to liver)
inferior pole - L3/L4
what level is the renal hilum at?
L1 ish - left renal vein passes over the aorta just inferior to where the SMA branches
gonadal branch distal to this from aorta
describe the flow of urine out of the kidney
tubules (within medullary pyraminds), papilla, minor calyx, major calyx, renal pelvis, ureter, bladder, urethra
label the kidney
renal column is where the vessels run between the pyramids
what 2 large muscles overly the posterior kidney
quadratus lumborum and psoas major
describe how the renal artery branches in the kidney
anterior/posterior, each give 5 segmental branches, interlobar arteries, arcuate arteries which then give of interlobular (tiny) arteries
