The Abdomen Flashcards
what are the four quadrants of the abdomen?
right and left upper, right and left lower
how are the 9 regions split?
2 midclavicular lines
2 horizontal lines:
1) through the lower costal margin crossing the 10th costal cartilage
2) through the tubercles of the pelvis sitting at l5
what are the 9 regions?
- right and left hypochondrium (below costal cartilage)
- epigastric (above belly)
- umbilical region
- hypogastric (below belly)
- iliac region left and right
- lumbar left and right
what is the function of the abdominal wall?
- protects abdominal viscera
- involved in actions that increases intra abdominal pressure eg coughing, vomiting, defacation
- maintain posture and move the trunk
how many groups of muscles are in the anterolateral abdomen and what are they?
2 - flat muscles, vertical muscles
how many flat muscles are there in the anterolateral abdomen and where are they located?
there are 3 flat muscles, found laterally on either side of the abdomen
how many vertical muscles are there in the anterolateral abdomen andwhere are they located?
there are 2 - lie on either side of the midline
what is an aponeurosis?
a broad flat tendon covering the vertical rectus abdominus. the aponeurosesis of all the flat muscles become entwined in the midline forming the linea alba
what is the linea alba?
tough midline structure that extends from xiphoid process of the sternum to the pubic symphysis
what is the external oblique?
the largest and most superficial flat muscle.
fibres run inferomedially
anterior wall of rectus sheath
what are the internal obliques?
lies deep to the external oblique. fibres run superomedially
what are the transverse abdominal obliques?
deep to internal obliques.
fibres run horizontally
posterior wall of rectus sheath
how many vertical muscles of the antolateral abdominal wall are there and what are they?
2 - rectus abdominis and pyramidalis
what is the rectus abdominis?
long flat muscle that spans the entire anterior abdominal wall.
what intersects the rectus abdominis?
tendinous intersections and linea alba give rise to six pack
what is the rectus sheath and how is it formed?
formed by the aponeuroses of the 3 flat muscles and encloses the rectus abdominis and pyramidalis muscles.
what makes up the anterior wall of the rectus sheath?
aponeuroses of external oblique and 1/2 internal
what makes up the posterior wall of the rectus sheath?
aponeuroses of 1/2 internal oblique and transverse abdominal
what is the peritoneum?
serous lining of the abdomen
how many layers are there in the peritoneum?
2 layers - parietal and visceral
what is the parietal peritoneum?
lines inner aspect of abdominal wall.
what is the visceral peritoneum?
covers structures and organs
what is the peritoneal cavity and what does it contain?
thin cavity between the parietal and visceral layers - contains a small amount of peritoneal fluid that allows the visceral to slide alongside eachother
what does retroperitoneal mean?
behind peritoneal
what is mesentry and what does it do?
double layer of visceral peritoneum
contains fat and suspend small intestine and part of the large from posterior abdomen wall.
provides a pathway for nerves, blood vessels, and lymphatics from body wall to the viscera
where is the stomach located?
lies within the superior aspect of the abdomen between the duodonem and oesophagus
what regions does the stomach cover?
primarily lies in the epigastric and umbilical regions
how many anatomical divisions are there in the stomach and what are they?
4 - cardia, fundus, body, pyloris
what is the cardia in the stomach?
surrounds the superior opening of the stomach at T11 level
what is the fundus in the stomach?
the rounded, often gas filled portion, superior to and left of the cardia
what is the body of the stomach?
the large central portion inferior to the fundus
what is the pyloris of the stomach?
connects the stomach to the duodonem. divided into atrum, canal, and sphincter
what is the greater curvature of the stomach?
long , convex, lateral border
what is the lesser curvature of the stomach?
shorter, concave, medial surface
where is the pyloric sphincter and what does it do?
lies between the pylorus and the first part of the duodenum - controls the exit of chyme (food and gastric acid mixture)
where does the arterial supply to the stomach come from?
coeliac trunk and its branches
what are the 3 sections of the small intestine?
duodenum, jejunem, ilium
what is the duodenum and where does it run?
the most proximal part of the small intestine, running from the pylorus of the stomach to the duodenojejunal junction
how many parts can the duodenum be divided into and what are they?
4 parts - superior, descending, inferior, and ascending
what shape is the duodenum
c shaped
describe the superior section of the duodenum
ascends upwards from the pylorus of the stomach, connected to the liver by the hepatoduedenal ligament
describe the descending duodenum
curves inferiorly around the head of the pancreas.
internally marked by the major duodenal papilla - the opening at which bile and pancreatic secretions enter from the ampulla of vater
describe the inferior duodenum
travels laterally to the left
crosses over the inferior vena cava and aorta
describe the ascending aorta
ascends and curves anteriorly to join the jejunem at a sharp turn known as the duodenojejunal flexure
describe the jejunem and ilium
distal two parts of the small intestine
they are intraperitoneal
what does the jejunem have that the ilium doesnt?
longer vasa recta
more pilcae circulares
less prominent arterial arcades
where is the large intestine?
distal part of the GI tract, extending from the cecum to the anal canal
how many parts of the large intestine are there and what are they?
4 - ascending, transverse, descending, and sigmoid
describe the ascending colon
retroperitoneal
ascends superiorly from the cecum
what is the right colic structure?
when the ascending colon meets the right lobe of the lung, it turns 90 degrees horizontally = start of transverse colon
describe the transverse colon
- extends from right colic flexure to the spleen, where it turns 90 degrees to face inferiorly = left colic flexure
- least fixed part of the colon
- intraperitoneal
- colon attached to diaphragm
describe the descending colon
- moves inferiorly towards pelvis
- retroperitoneal
- located anteriorly to kidney, passing over its lateral border
describe the sigmoid colon
- when colon turns medially = sigmoid colon
- extends from left iliac fossa to level of S3 vertebra
- attached to posterior pelvic wall via sigmoid mesocolon
what are the omental appendices?
small pouches of peritoneum filled with fat
what are teniea coli?
3 strips of muscle that run longitudinally along surface of large bowel
what are the haustra?
sacculation produced when the teniea coli contract to shorten the wall of the bowel
