LECTURE 2- abdominal wall and peritoneum Flashcards
superior boundary of the abdomen
inferior thoracic apeture and diaphragm
inferior boundary of the abdomen
iliac crest, inguinal ligament, pelvic inlet
posterior boundary of the abdomen
lumbar vertebral column, psoas maj, quadratus lumborum
lateral and anterior boundary of abdomen
abdominal wall muscles
what are the 9 regions of the abdomen
down the middle: epigastric- umbilical- pubic
the sides: hypochondrium- flank- groin
what are the layers of the abdominal wall from superficial to deep
skin- superficial fascia- ext oblique- int oblique- transversus abdominis- transversalis fascia- extraperitoneal fascia- parietal peritoneum
fibre direction of rectus abdominis
longitudinal
function of recuts abdominus
flex trunk
support/ compress abdominal wall
innervation of rectus abdominus
anterior rami of thoracic spinal nerves
external oblique aponeurosisi
from xyphoid process to pubic symphysis (lower border forms inguinal lig)
external oblique action
flex trunk
bend trunk to same side
turn to opposite side
innervation of external oblique
anterior rami of thoracic spinal nerves
fibre direction of external oblique
infero medial (hands in pockets)
internal oblique action
flex trunk
bend and turn to same saide
internal oblique innervation
anterior rami of thoracic spinal nerves
and some L1
internal oblique fibre direction
superomedial ( up to boobs)
transversus abdominus action
supports abdominal wall
transversus abdominus innervation
anterior rami of thoracic spinal nerves
some L1
what divides the rectus sheath into 3/4 and 1/4
the arcuate line (which is halfway along the line from the umbilicus to the pubic bones)
what happens in the upper 3/4 of the rectus sheath
all 3 abdominal wall muscles surround rectus abdominis
external oblique above
internal oblique splits
transversus abdominus below
what happens below the arcuate line in the lower 1/4 of the rectus sheath
rectus sheath is in front of rectus abdominis only
behind is transversalis fascia and parietal peritoneum
what is the arcuate line
halfway along the line from the umbilicus to the pubic bones
what is the arterial supply of the rectus sheath
superior epigastric (from internal thoracic) inferior epigastric (from external iliac)
both these arteries run underneath rectus abdominus (on top of transversalis fascia) and within the rectus sheath and ANASTAMOSE together
what dermatomes supply the skin, muscle and parietal pertoneum of teh abdomen
t7-12 and L1
all of these nerves are anterior rami
where do the anterior rami run in the neurovascular plane
run between transversus abdominis and internal oblique (analogous to the intercostal neurovascular plane)
before piercing the muscular wall to reach the skin
nerves that supply rectus sheath
lower 6 intercostal nerves t7-12 and L1 (iliohypogastric)
between which 2 muscles do the nerves travel though
in between internal oblique and transversus abdominis
what are the 2 pathways of venous tdrainiabe in the abdomen
axillary vein superiorly
femoral vein inferiorly
what is the lymphatic drainage of the abdomen
superior abdomen- axillary nodes
inferior abdomen- groin and superior inguinal nodes
do the superficial lymphatics and deepy lymphatics follow the arteries or veins
superficial lymphatic= arteries
deep lymphatics= veins
what does the visceral peritoneum cover
abdominal organs
what does the parietal peritoneum cover
lines the body wall
what supplies the parietal peritoneum
- somatic nerves to the body wall (thoracic and lumbar nerves)
- phrenic nerves- up by diaphragm
- obturator nerve- down in pelvis
SOP
what is the parietal peritoneum sensitive to
touch, pain, temperature, pressure
what type of pain is felt in the parietal peritoneum
localised pain
what is the nervous supply of the visceral peritoneum and the mesenteries
afferent fibres of the autonomic nervous system
what is the visceral peritoneum and the mesenteries sensitive to
stretch eg when you eat too much
what kind of pain is felt in the visceral peritoneum and the mesenteries
de-localised pain
what is mesentery
when visceral perotneum comes back around on itself
anchors viscera to the body wall
what mesentery(s) suspends the midgut and hindgut
only one mesentery- the DORSAL
what mesentery(s) susupends the foregut
by both DORSAL and VENTRAL mesenteries
which organs in the abdomen are retroperitoneal
SAD PUCKER
S(adrenal gland)
aorta/ ivc
duodenum (distal 2/3)
Pancreas (except tail Ureters Colon (ascending and descending) Kidneys Esophagus Rectum
acronym for retroperitoneal organs
SAD PUCKER
where is the lesser sac located
behind the lesser omentum, liver and the stomach
how was the lesser sac created
created due to rotation of the foregut strucutres (drags lesser omentum round to create a pocket)
where is the greater omentum derived from
the dorsal mesentery
big dick
where is the lesser omentum derived from
ventral mesentery
v=L
what is the opening to the lesser sac called
the omental foramen
foramen of winslow
epiploic foramen
what is in the free edge of the lesser omentum
the portal triad
what is the hepatoduodenal ligament
part of the lesser omentum
extending between the porta hepatis of the liver –> superior part of the duodenum.
what is the hepatogastric ligament
connects the liver –> lesser curvature of the stomach.
It contains the right and the left gastric arteries.
In the abdominal cavity it separates the greater and lesser sacs on the right.
which 2 ligaments make up the lesser omentm
hepatogastric (medial) and hepatoduodenal (lateral) ligaments
what does the greater omentum attach to
the greater curvature of the stomach
what suspends the jejenum to the terminal ileum
mesentery
what suspends the transverse colon
transverse mesocolon
what suspends the sigmoid colon
sigmoid mesocolon
what are paracolic gutters
peritoneal sulci to the lateral and ascending colons
what is the function of the paracolic gutters
create a pathway for peritoneal fluid, pus, bile, blood etc to migrate around the abdomen
why is the right paracolic gutter more clinicallly significant than the left
the right side is a bit larger
(the left is limited by the phrenico-colic ligament)
the right side of the peritoneum = continusous with the peritoneum of the hepatic recess and lesser sac
what is the clinical significance of the paracolic gutter
migration of fluids can cause pain to present in sites that are distant from the site of the affected organ
eg if sitting fluid migrates downwards and presents as acute appendicitis
but if standing it migrates into the lesser sac and collects there
