Abdomen Flashcards
What are the bony landmarks that define the borders of the abdomen?
xiphoid process, inferior border of costal cartilages, iliac crest, inguinal ligament, public bone
What rib level is the highest part of the diaphragm?
5th intercostal space
what is the subcostal plane?
axial line between the lowest part of the thoracic cage either ribs or costal cartilages - at level L3
Where is the intertubercular plane?
axial line between the ASIS - at level L5
What are the four lines that divide the abdomen into 9 sections?
subcostal plane, intertubercular plane and both mid-clavicular lines
what are the names of the 9 sections of the abdomen?
hypochondrium x2, epigastrium, flank x2, umbilical region, iliac x2, supra-pubic/hypogastrium,
Where is the transpyloric plane?
axial line across tips of 9th rib, the most lateral point where rectus abdominis attaches at level L1
Where is mc-burney’s point?
2/3rd of the way from the umbilicus to the ASIS
What are the three muscle layers of the abdomen?
external oblique, internal oblique, transversus abdominis
At which point do the 3 abdominal wall muscle layers aponeurose?
Mid-clavicular line
Where does the rectus abdominis muscle attach to?
O: pubic crest
I: ribs 5,6,7, xiphoid process
What is an aponeurosis?
also known as rectus sheath, a sheet of tendinous tissue
What is the linea alba?
fibrous structure down the midline of the abdomen - no structures cross
What are the two most superficial layers of fascia in the abdomen?
campers and scarpa’s fascia
What is campers fascia?
The most superficial fatty fascial layer of the abdomen
What is scarpa’s fascia?
The second-most superficial membranous fascial layer of the abdomen
Does the rectus sheath lie in-front of or behind rectus abdominis?
upper 2/3rds: surrounds muscle
lower 1/3rd: lies in-front of muscle
Does the internal oblique aponeurosis lie behind or in-front of rectus abdominis?
upper 2/3rds: half goes behind and half in front
lower 1/3rd: all in front
Which nerve covers the dermatome that includes the umbilicus?
T10
Which nerve covers the dermatome that includes the hair-bearing area of the pubis?
L1
What nerve roots does the greater splanchnic nerve come from? (Foregut)
T5-T9
What nerve roots does the lesser splanchnic nerve come from? (Midgut)
T10, T11
What nerve root does the least splanchnic nerve come from? (Hindgut)
T12
What are the four muscles of the abdominal wall?
ext oblique, int oblique, transversus abdominis, rectus abdominis
what is the falciform ligament?
carries ligamentum teres from umbilicus to left portal vein
At what level does the oesophagus pass through the diaphragm?
T10
What are the five parts of the stomach?
Fundus, cardia, body, antrum, pylorus
Where is the pyloric sphincter?
Between the stomach and the duodenum
At what point does the duodenum become the jejunum?
When it develops a mesentery
Which part of the large bowel comes first in the digestive tract?
Caecum - with appendix
What are the two flexures of the large bowel called?
Hepatic and splenic flexure
What divides the right and left infra-colic department?
Small bowel mesentery
Where is the greater omentum attached to?
The greater curve of the stomach
Where is the lesser omenrum attached to?
The lesser curve of the stomach, the duodenum and the liver
Where is the lesser sac?
Behind the lesser omentum
What is the foramen of winslow/epiploic foramen?
The opening into the lesser sac
what are the two arteries that supply the lesser curve of the stomach?
right gastric (from common hepatic), left gastric artery (from coeliac trunk)
What are the two arteries that supply the greater curve of the stomach?
left (from splenic) and right (from gastroduodenal artery) gastro-epiploic or gastro-omental arteries
What is the blood supply to the fundus of the stomach?
short and posterior gastric artery - branches of splenic artery
What is the blood supply to the pylorus of the stomach?
Gastroduodenal artery - branch of common hepatic
What is the omentum made up of?
Two double layers of peritoneum containing a neurovascular bundle and lymphatics
Which organ lies directly behind the lesser sac?
The pancreas
What is the name of the folds of the stomach wall?
Rugae
Where is the duodenal-jejunal flexure?
left upper quadrant deep to the transverse colon, where the small bowel comes through the peritoneum
Which areas of the large bowel are mobile?
Transverse and sigmoid colon - attached via mesentery
Name some differences between the large and small intestine
lg: teniae coli, epiploic appendages, haustra,
sml: peyer’s patches, smooth wall, villi inside
What is the difference between the jejunum and ileum blood supply?
J: larger vessels, Long arcades, long vasa recti
I: smaller vessels, much more smaller arcades, short vasa recti
What is the name of the folds in the jejunum?
Plicae circulares
What are the four things that the small bowel has to increase its surface area?
Length, plicae circulares, villi, microvilli
What is the difference between the jejunum and ileum?
fewer plicae circulares in the ilium. more peyers patches in ilium, more fat in mesentery of ileum
What are haustra?
Small pouches in the bowel caused by sacculation
What is the blood supply to the thoracic oesophagus?
inferior thyroid artery, direct from the aorta, left gastric
What is the blood supply to the abdominal aorta?
oesophageal artery branches from left gastric artery
What are the five parts of the pancreas?
tail, body, neck head, uncinate process
What are the four parts of the duodenum?
Superior, descending, inferior, ascending
In which part of the duodenum do the papillas exist?
Descending portion
What are the attachments of the diaphragm?
lumbar vertebrae, costal cartilages of ribs 7-10, ribs 11-12, xiphoid process
What are the attachments of the crura of the diaphragm?
right: L1-L3
Left: L1-L2
What structures pass through the diaphragm at T8?
Inferior vena cava, right phrenic nerve
What structures pass through the diaphragm at T10?
oesophagus, right and left vagus nerve, left gastric artery and vein
What structures pass through the diaphragm at T12?
Aorta, thoracic duct, azygous vein
At which level does the aorta bifurcate?
L4/L5
What is the surface marking of the gallbladder?
Midclavicular line, tip of 9th costal cartilage
Where is pain from the gallbladder felt?
Epigastric T5,6,7,8,9 supplies gallbladder - so those dermatomes
Where is pain felt if the gallbladder rubs on the peritoneum?
Sharp pain at tip of 9th rib
Where is pain felt if the gallbladder rubs on the diaphragm?
Tip of the right shoulder, C3/4/5 supplies the diaphragm
What are the three main branches of the coeliac trunk?
Common hepatic artery, left gastric artery and splenic artery
Where is bile produced?
The liver
What is the portal triad made up of?
Hepatic artery, common bile duct and hepatic portal vein
What separates the right and left lobe of the liver?
The falciform ligament
From which area of the digestive tract does the portal vein drain blood from?
Lower 1/3rd of oesophagus to rectum
Where does the IVC sit in relation to the liver?
Posterior to the anatomical middle of the liver
What are the four lobes of the liver?
Left, right, caudate, quadrate lobe
What structures does the caudate lobe of the liver sit between?
IVC and attachment to lesser omentum
Where is the anterior coronary ligament?
Antero-superior aspect of the right lobe of the liver, just above the bare area of the liver. Attachment of peritoneum to liver.
Where is the posterior coronary ligament?
Postero-superior aspect of the right lobe of the liver. Attachment of peritoneum to liver.
Where is the left triangular ligament of the liver?
On the superior aspect of the left lobe of the liver
Which artery do the short gastric arteries arise from?
Splenic artery
Which two veins join to form the hepatic portal vein?
Superior mesenteric vein and splenic vein
What is the sphincter of oddi?
The sphincter that controls bile release from the common bile duct and pancreatic duct into the duodenum
What is the ampulla of vater?
Formed by the joining of the common bile duct and pancreatic duct at the major duodenal papilla
Do the pancreatic and common bile duct join before or after the sphincter of oddi?
After - to prevent refluxing of ductal contents. The sphincter still controls outputs from both ducts
What level is the subcostal plane?
L3
What level is the intertubercular plane?
L5
Name the two superficial branches of the lower intercostal nerves
anterior and lateral cutaneous
What does the iliohypogastric nerve supply?
Transversus abdominis, internal oblique, conjoint tendon
What is the path of the iliohypogastric nerve?
L1 - travels posterior to kidneys - pierces transversus abdominis - continues between trans abdo and internal oblique
What is the conjoint tendon?
aponeurosis of trans abdo and internal oblique
What are the actions of external oblique?
ipsilateral trunk lateral flexion, contralateral trunk rotation
What are the actions of internal oblique?
ipsilateral trunk lateral flexion, ipsilateral trunk rotation
What are the attachments of the inguinal ligament?
ASIS and pubic tubercle
Which blood vessel lies posterior to the caecum?
Gonadal vessel
What level do the testicular arteries come off the aorta?
L2
What level is the coeliac trunk?
T12
What level is the superior mesenteric artery?
L1
What level is the inferior mesenteric artery?
L3
At what level does the aorta bifurcate?
L4
What level do the common iliac arteries bifurcate?
L5
What level does the left renal artery come of the aorta?
L1
What is the nerve supply to the upper half of the oesophagus?
Recurrent laryngeal nerve
Where is the superficial inguinal ring?
1.25cm above the pubic tubercle
Where is the deep inguinal ring?
At the midpoint of the inguinal ligament, 1.25cm above the ligament
What is the deep inguinal ring?
An invagination of the transversalis fascia
What is the superficial inguinal ring?
A triangular gap within the aponeurosis of external oblique
What forms the anterior wall of the inguinal canal?
Aponeurosis of external oblique (A)
What forms the posterior wall of the inguinal canal?
Transversalis fascia, conjoint tendon (T)
What forms the roof of the inguinal canal?
Conjoint tendon - made up of internal oblique and transversus abdominis (M)
What forms the floor of the inguinal canal?
Inguinal ligament and lacunar ligament (L)
What are the contents of the inguinal canal?
Spermatic cord (m), round ligament (f), ilioinguinal nerve and genital branch of the genitofemoral nerve
What does the lateral (inferior) crus of the superficial inguinal ring attach onto?
Fibres arch over the contents of the inguinal canal and attach onto the Pubic tubercle
What does the medial (superior) crus of the superficial inguinal ring attach onto?
Pubic crest
What do the intercrural fibres of the superficial inguinal ring do?
Stop the crura from spreading apart
Which ring does the ilioinguinal nerve pass through?
Superficial inguinal ring. It enters the canal part way through the roof, and does not go through the deep ring
Which nerve passes through both rings of the inguinal canal?
The genital branch of the genitofemoral nerve
What are the attachments of the internal oblique muscle?
O: anterior 2/3rds of iliac crest
I: Ribs 10-12, linea alba
What are the attachments of the external oblique muscle?
O: ribs 5-12
I: Linea alba, pubic tubercle
What are the attachments of transversus abdominis muscle?
O: Ribs 7-12, anterior 2/3rds of iliac crest
I: linea alba, pubic crest, aponeurosis of internal oblique
Where does the abdominal linea alba run from?
xiphoid process to pubic symphysis
What are the attachments of rectus abdominis?
O: Pubic symphysis, pubic crest
I: Xiphoid process, costal cartilages of ribs 5-7
What is the function of the pyramidalis muscle?
It tenses the linea alba, acting with abdominal wall muscles to increase intra-abdominal pressure
What are the attachments of the pyramidalis muscle?
O: Pubic crest, pubic symphysis
I: Linea alba
What artery does the inferior epigastric artery come off?
External Iliac artery
Where does the inferior epigastric artery lie in relation to the inguinal canal?
The arteries lie just medially to the deep inguinal ring, and arise just superiorly to the inguinal ligament
