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