Anatomy Flashcards
At what level does the celiac trunk appear? What does it supply?
T12/upper L1; supplies the foregut (ABD esophagus -> superior to major duodenal papilla)
At what level does the SMA appear? What does it supply?
Lower L1; supplies the midgut (inferior to major duodenal papilla -> proximal 2/3 transverse colon)
At what level does the IMA appear? What does it supply?
L3; supplies the hindgut (distal 1/3 transverse colon -> midway through anal canal)
At what level does the aorta bifurcate?
L4
What 3 branches come off the celiac trunk?
Left gastric A.; splenic A.; common hepatic A.
In what L. does the left gastric A. lie? What branches come off it?
hepatogastric L.; gives off esophageal As.
Name the 4 branches of the splenic A. Is the splenic A. intraperitoneal or retroperitoneal?
- pancreatic branches; splenic branches; short gastric As.; left gastro-omental A.
- retroperitoneal until it enters the splenorenal L. (along w/ tail of pancreas)
Name the 3 branches off of the common hepatic A.
right gastric A., proper hepatic A., and gastroduodenal A.
In what L. is the proper hepatic A.? Name 3 branches off of it
- hepatoduodenal L.
- left hepatic A., right hepatic A., cystic A. (can come off proper hepatic or right hepatic A.)
Name the 3 branches of the gastroduodenal A.
supraduodenal A.; right gastro-omental A.; superior pancreaticoduodenal A. (anterior and posterior branches)
What is Pringle’s maneuver?
surgical maneuver to control hemorrhaging of the cystic A. by clamping the hepatoduodenal L. (can be used during cholecystectomy)
Name the 6 branches of the SMA
inferior pancreaticoduodenal As (anterior and posterior branches); jejunal As.; ileal As.; middle colic A.; right colic A.; ileocolic A.
How do you distinguish between jejunum and ileum?
jejunal As. have large arcades and long vasa recta; ileal As. have small arcades and short vasa recta
Name the 2 branches of the ileocecal A.
cecal branch and appendicular A.
Name the 3 branches off of the IMA
left colic A., superior rectal A., and sigmoid As.
Name 3 upper GI anastamoses
- left gastric A. and right gastric A. (lesser curvature of stomach)
- left gastro-omental A. and right gastro-omental A. (greater curvature of stomach)
- superior and inferior pancreaticoduodenal As. (anterior and posterior branches)
What is Nutcracker syndrome? What are some sxs?
- compression of the left renal vein between the SMA (anterior) and the ABD aorta (posterior)
- sxs include hematuria, left flank pain, N/V, left testicular pain in men
Where do the left and right gonadal Vs. drain?
left gonadal V. drains into left renal V.
right gonadal V. drains into IVC
What forms the hepatic portal vein?
merging of the splenic V. and superior mesenteric V.
What are 3 locations that the inferior mesenteric V. can drain?
- directly into hepatic portal vein (1/3)
- into splenic vein or superior mesenteric vein (2/3)
What porto-caval anastomosis would cause esophageal varies?
esophageal V. (from L. gastric V.) with esophageal V. (from Azygos V.)
What porto-caval anastomosis would cause hemorrhoids?
superior rectal V. (continues as IMV) with inferior rectal V. and middle rectal V.
What porto-caval anastomosis would cause caput medusae? What is caput medusae?
- para-umbilical Vs (dump directly into hepatic portal V.). w/ epigastric Vs.
- veiny webbing of dilated vessels around umbilicus (seen in very severe liver cirrhosis)
What is the 4th porto-caval anastomosis?
visceral Vs. with retroperitoneal Vs of posterior ABD wall and diaphragm
What divides the rectum into 2 regions? What is each region derived from?
pectinate line; above the line is made of endoderm; below the line is made of ectoderm
What is the artery and vein from the superior part of the rectum? What supplies the artery and where does the vein drain?
superior rectal A. (from IMA)
superior rectal V. (IMV -> portal system)
What is the artery and vein from the inferior part of the rectum? What supplies the artery and where does the vein drain?
inferior rectal A. (from internal pudendal A.)
inferior rectal V. (internal pudendal V. -> internal iliac V. -> common iliac V. -> IVC)
Internal vs External Hemorrhoids?
- internal occur above the pectinate line (visceral innervation - not painful)
- external occur below the pectinate line (somatic innervation - painful)
What is the most common portosystemic shunt?
central splenorenal shunt - between splenic V. and left renal V.
What is the major differences between CT and MRI?
CT - fast, all data collected at once, involves radiation (Xray)
MRI - slow, no radiation (not Xray), have to set parameters for proper info
What is the modality of choice for viewing the biliary tree?
endoscopic retrograde cholangiopancreatography (ERCP)
What is the modality of choice for viewing ABD aortic vasculature?
digital subtraction arteriography
What is ascites and the most common causes (5)?
- accumulation of fluid in the ABD
- portal HTN, liver cirrhosis, salt and water retention, heart failure, cancer
Why don’t you see ascites around the kidneys?
kidneys are retroperitoneal
What is a mid-sagittal view useful for assessing?
SMA syndrome and Nutcracker syndrome
What is Superior Mesenteric Artery Syndrome? When is it mostly seen and what are the sxs?
compression of the 3rd part of the duodenum between the ABD aorta and SMA; usually seen in people after large amounts of weight loss; sx include ABD pain, fullness, N/V, and weight loss
sliding hiatal hernia vs paraesophageal hiatal hernia
- sliding hiatal hernia: bulging of stomach through LES (reflux)
- paraesphageal hiatal hernia: bulging of fundus up next to esophagus (no reflux)
What is zenker’s diverticulum? Sxs?
diverticular formation in esophageal wall next to inferior pharyngeal constrictor; sxs include severe halitosis, dysphagia, feeling of food stuck in throat, regurgitation hours after eating
What is ulcerative colitis? What is the hallmark of it?
spasm of the longitudinal muscle and/or irreversible fibrosis; hallmark is the “lead pipe” appearance of colon due to loss of haustral markings
What is the test of choice for dx cholelithiasis?
Gallbladder US
What is a shatzki ring?
narrowing of the esophagus caused by a ring of mucosal tissue or muscular tissue
What is the cause of Hischprung’s disease? What is the tx?
absence of parasympathetic post-ganglionic plexus due to absence of NCC migration; causes megacolon and lack of peristalsis; tx is surgical resection of affected area
What is the origin, insertion, and innervation of the psoas major and minor Ms.?
O: transverse process and bodies of T12-L5
I: tendon of lesser trochanter or femur
N: L1-L3
What is the origin, insertion, and innervation of the iliacus M.?
O: superior 2/3 of iliac fossa and iliac ala
I: lesser trochanter of femur; travels w/ psoas major M. at level of inguinal L. and unite and insert together
N: femoral N. (L2-L4)
What is the origin, insertion, and innervation of the quadratus lumborum M.?
O: inferior 12th rib, tp of lumbar transverse processes
I: iliolumbar L., lip of iliac crest
N: T12-L4
What is the median arcuate L. of the posterior ABD wall?
tendinous arch crossing aorta; unites left and right crura of diaphragm
What is the medial arcuate L. of the posterior ABD wall?
lateral to median arcuate L. on each side; fascial thickening of psoas M. from lumbar body to TP
What is the lateral arcuate L. of the posterior ABD wall?
fascial thickening of quadratus lumborum M. that spans from L2 TP to tip of 12th rib
What are the 3 muscular parts of the diaphragm?
- sternal: attaches to xiphoid process
- costal: attaches to inferior 6 costal cartilages
- central tendon: central part of diaphragm
What are the crura of the diaphragm? Which is longer?
- tendons that extend below the diaphragm on the vertebral column to help muscle contraction
- right crus extends further (L3-L4) than the left crus (L2-L3)
What are the 3 diaphragmatic openings and at what level are they?
- caval (T8)
- esophageal (T10)
- aortic hiatus (T12)
What runs through each of the 3 diaphragmatic openings? Mnemonic?
I 8 10 Eggs At 12
- T8: IVC and right phrenic N.
- T10: esophagus, anterior and posterior vagal trunks
- T12: aortal and thoracic duct
What are the 6 arteries that supply the diaphragm?
- superior phrenic A.
- inferior phrenic A.
- pericardiocophrenic A.
- musculocophrenic A.
- superior suprarenal A.
- intercostal As.
From what levels does the ABD aorta run? Where does it bifurcate?
runs from T12-L4 then bifurcates
Name 4 unpaired As. of the posterior ABD wall. What do they all come from?
all come from ABD aorta
- celiac trunk (T12)
- SMA (L1)
- IMA (L3)
- median sacral A. (L4 at bifurcation)
Name the 7 pairs of arteries of the posterior ABD wall.
- inferior phrenic As.
- subcostal As.
- lumbar As.
- suprarenal As.
- Renal As.
- deep circumflex As.
- gonadal As.
At what level do both renal As. and gonadal As. come off ABD aorta?
L2
Name 3 visceral veins of the posterior ABD wall
drain organs
- suprarenal V.
- renal V.
- gonadal V.
Name 3 parietal veins of the posterior ABD wall
drains body cavity
- inferior phrenic V.
- lumbar V.
- common iliac V. (where ABD aorta and IVC bifurcate)
At what level does the IVC begin and where does it run?
L5; runs slightly to the right of the ABD aorta
What drains into the common iliac lymph nodes?
internal and external iliac lymph nodes (pelvic region)
What does the common iliac lymph nodes drain into? Where do these lymph nodes receive lymph and where do they run?
- lumbar lymph nodes (posterior ABD wall, pelvic wall, and organs in region)
- run along side the IVC and aorta
Where do they pre-aortic lymph nodes lie and what do they drain?
lie in front of the aorta and drain the GI tract, liver, spleen, and pancreas
Where does all lymph of the lower body collect?
cysterna chyli
What 6 nerves of the posterior ABD wall are part of the lumbar plexus?
- iliohypogastric N.
- ilioinguinal N.
- lateral femoral cutaneous N.
- femoral N.
- obturator N.
- lumbosacral trunk
What makes up the subcostal N. and where does it run?
T12; runs underneath 12th rib (protected)
What makes up the iliohypogastric N. and ilioinguial N.? When are they likely to be damaged?
L1; likely to be damaged if kidney is damaged (run over kidneys on posterior side)
What makes up the genitofemoral N. and where does it run?
L1-L2; runs on top of psoas major M.
What makes up the lateral femoral cutaneous N.?
L2-L3
What makes up the femoral N. and obturator N.?
L2-L4
What makes up the lumbosacral trunk?
L4-L5
What 3 nerves of the posterior ABD wall run lateral to the psoas major M.?
- ilioinguinal N.
- lateral femoral cutaneous N.
- femoral N.
What nerve of the posterior ABD wall runs medial to the psoas major M.?
obturator N.
At what level are the kidneys? Which one is lower and why?
T12-L3; right kidney is lower due to the liver
What lies over the inferior pole of each kidney?
quadratus lumborum M.
What is the innervation of the kidneys?
renal plexus as well as least pelvic splanchnic Ns. (aorticorenal ganglion); also innervated by vagal trunk
What are the 3 layers of renal fascia?
- perinephric fat (surrounds kidney directly)
- renal fascia: covers perinephric fat and suprarenal gland
- paranephric fat: outside renal fascia
What does the renal A. split into?
segmental As going to each segment of the kidneys
Where do the ureters run in males and females?
posterior to ductus deferens in males; posterior to uterine A. in females
What are 3 constriction points for the ureters?
- ureterophelvic junction (UPJ) -> junction of ureter w/ renal pelvis
- pelvic brim
- where it enters bladder wall
Name 6 arteries that supply the ureters?
- renal A.
- gonadal A.
- ABD arota
- common iliac A.
- superior vesicular A.
- pelvic branches
What is the innervation of the ureters (4)?
- renal plexus
- ABD aortic plexus
- superior hypogastric plexus
- sympathetics: T11-L2
What sits next to the right adrenal gland?
right crus of the diaphragm and IVC
What sits next to the left adrenal gland?
left crus of diaphragm, spleen, stomach, and pancreas
Where do each of the 3 suprarenal As. come off?
- superior suprarenal As. -> inferior phrenic A.
- middle suprarenal As. -> ABD aorta
- inferior suprarenal As. -> renal A.
What innervates the adrenal glands (2)? What do they receive parasympathetic and sympathetic innervation?
- celiac plexus
- ABD pelvic splanchnic Ns.
- parasympathetics: vagal trunks
- Autonomics: T10-T11 that synapse on chromatin cells inside medulla
Where do both sympathetic and parasympathetic nerve fibers leave the spinal cord?
- Sympathetic: thoracolumbar
- Parasympathetic: craniosacral
Preganglionic neuron vs postganglionic neuron
- preganglionic neuron - originated in CNS (brain stem or spinal cord) and synapses on a ganglion in the PNS
- postganglionic neuron - travels to the target organ
What do sympathetic fibers look like compared to parasympathetic fibers?
- sympathetic fibers: short presynaptic/long postsynaptic
- parasympathetic: long presynaptic/short postsynaptic
What is the function of both sympathetic and parasympathetics?
- sympathetics: respond to stress, vasoconstriction, and reduce bowel motility and secretions
- parasympathetic: maintain homeostasis, increase bowel motility, secretion, and vasodilation
What is a paravertebral ganglion?
What is a prevertebral ganglion?
- paravertebral ganglion: interconnected ganglia that lie close to the vertebra and spinal cord
- prevertebral ganglion: sympathetic ganglia that lie between the paravertebral ganglia and the target organ
What synapses onto prevertebral sympathetic ganglia?
presynpatic sympathetic fiber; parasympathetic fibers do not synapse onto it -> skip it and synapse closer to the target organ
What are the 4 choices presynaptic fibers have when they leave the spinal cord?
- go up paravertebral chain and synapse on another ganglia
- go down the chain and synapse
- come out and synapse at that level
- pass through ganglia w/o synapsing and synapse on prevertebral ganglia (visceral)
Onto what ganglia do the greater, lesser, and least splanchnic Ns. synapse? What levels make them up?
- greater (T5-T9) -> celiac ganglion
- lesser (T10-T11) -> superior mesenteric ganglion
- least (T12) -> aroticorenal ganglion
Name 2 more splanchnic nerves and their levels
- lumbar splanchnic (L1-L3)
- sacral splanchnic (S1-S5) -> not anterior rami (sympathetic)
What splanchnic nerve is actually parasympathetic rather than sympathetic? What are its levels and what does it innervate?
pelvic splanchnic Ns. (anterior rami S2-S4) -> splenic flexure to above pectinate line in anal canal
Describe sympathetic innervation for the foregut and midgut
- foregut: presynaptic: thoracic splanchnic Ns. (T5-T9); postsynaptic: celiac ganglion
- midgut: presynaptic: thoracic splanchnic Ns. (T5-T9); postsynaptic: superior mesenteric ganglion
Describe sympathetic innervation of the hindgut
presynaptic: lumbar splanchnic Ns. (L1-L2); postsynaptic: inferior mesenteric ganglion
Describe parasympathetic innervation of the foregut, midgut, and hindgut
- foregut = vagus N.
- midgut = vagus N.
- hindgut = pelvic splanchnic Ns.
Where would referred pain be located in the foregut, midgut, and hindgut?
- foregut = epigastrium
- midgut = umbilicus
- hindgut = hypogastrium
What is located at the T4, L10, and L1 levels?
T4 = nipples T10 = umbilicus L1 = inguinal fold
Visceral afferents of liver
T6-T9
visceral afferents of stomach
T6-T9
visceral afferents of spleen
T6-T8
visceral afferents of pancreas
T6-T9
visceral afferents of adrenal glands
T6-L2
visceral afferents of kidneys
T10-L1
visceral afferents of small intestine
T8-T10
visceral afferents of appendix
T12
visceral afferents of the colon
T11-L1
visceral afferents below the pelvic pain line (midpoint of sigmoid colon)
parasympathetics (S2-S4)
reflex afferents below and above pelvic pain line
above = vagus N.
below = S2-S4
- parasympathetics only
Describe visceral pain
diffuse, dull, can cause referred pain
describe somatic pain
localized, acute or severe, supplied by somatic sensory fibers via thoracic nerves (T7-T12); extremely sensitive to stretching -> rebound tenderness
What usually causes referred shoulder pain?
irritation of the diaphragm