Posterior Abdominal Wall Flashcards
name 6 components of the posterior abdominal wall
- skeleton (5LV + IVD)
- muscles
- thoracolumbar fascia
- aa (abdominal aorta + branches)
- vv (inf vena cava + branches)
- nn
name the muscles that make up the posterior abdominal wall
- diaphragm
- psoas maj
- iliacus
- quadratus lumborum
- transversus abdominis
what is the primary muscle of respiration?
diaphragm
the diaphragm ____ during inspiration
descends
origins & insertion of diaphragm
O
- sternal: xiphoid process
- costal: internal surfaces of inf 6 costal cartilages
- lumbar: med + lat arcuate ligaments & L1-L3
I: central tendon
medial arcuate ligament travels from ____ to ____, and arches over ____
- body of L1 to TP of L1
- psoas major
lateral arcuate ligament travels from ____ to ____, and arches over ____
- TP of L1 to 12th rib
- quadratus lumborum
the right crus arises from ____
first 3-4 LV and IVDs
the right crus is ____ than the left crus
larger + longer
the left crus arises from ____
first 2-3 LV + IVDs
name 3 openings of the diaphragm and their spinal levels
- caval opening (T8)
- esophageal hiatus (T10)
- aortic hiatus (T12)
what passes through the caval opening?
IVC
(opening in central tendon)
what passes through the esophageal hiatus?
- esophagus
- right & left vagal trunks
the esophageal hiatus forms the ____
right crus
what passes through the aortic hiatus?
- aorta
- thoracic duct
- azygous & hemiazygous vv
the ____ is the opening posterior to the diaphragm
aortic hiatus
what forms the median arcuate ligament?
right & left crura unite in midline
what ligament forms the aortic hiatus?
median arcuate
arterial supply of diaphragm
- thoracic aorta (sup phrenic aa)
- internal thoracic aa (musculophrenic + pericardiophrenic aa)
- abdominal aorta (inf phrenic aa)
venous drainage of diaphragm
veins mirror aa and drain into IVC
innervation of diaphragm
- phrenic n (C3-C5): motor + sensory
- lower 6-7 intercostal nn (T5-T11): sensory
- subcostal n (T12): sensory
all motor innervation of the diaphragm comes from ____
phrenic n (C3-C5)
“keeps the diaphragm alive”
superior and inferior attachments of psoas major
sup:
- TPs of LV
- sides of T12-L5 bodies + IVDs
inf: lesser trochanter, femur
innervation of psoas major
ant rami of L1-L3
primary actions of psoas major
- flex thigh (w iliacus)
- flex trunk when sitting (w iliacus)
- flex vertebral column laterally
- balance trunk
superior and inferior attachments of iliacus
sup:
- sup 2/3 iliac fossa
- ala of sacrum
- ant sacroiliac ligaments
inf:
- lesser trochanter of femur & diaphysis inf to trochanter
- psoas maj tendon
innervation of iliacus
femoral n (L2-4)
primary action of iliacus
with psoas major, flexes thigh + stabilizes hip joint
superior & inferior attachments of quadratus lumborum
sup:
- medial 1/2 of 12th rib inf border
- tips of lumbar TPs
inf:
- iliolumbar lig
- internal lip of iliac crest
innervation of quadratus lumborum
- ant rami T12 (subcostal n)
- lumbar plexus (L1-4)
primary action of quadratus lumborum
- extend & laterally flex vertebral column
- fix rib 12 during inspiration
the abdominal aorta descends anterior to vertebral bodies of ____ to ____
T12 - L4
veins of the posterior abdominal wall drain directly into the ____, except for which veins?
IVC
left gonadal & left suprarenal vv
where does the inferior vena cava begin?
at L5 to right of midline
vertebral level of celiac trunk
T12
vertebral level of SMA
L1
vertebral level of renal arteries
L1
vertebral level of gonadal arteries
L2
vertebral level of IMA
L3
vertebral level of aortic bifurcation
L4
vertebral level of lumbar arteries
L1-L5
vertebral level of median sacral artery
L4
what forms cisterna chyli?
convergence of lumbar lymphatic trunk, intestinal lymph trunks, and descending thoracic trunks
all lymph from the lower 1/2 of the body drain into ____
cisterna chyli
location of cisterna chyli
- ant to L1-L2 vertebral bodies
- between IVC and abdominal aorta
the subcostal nerve runs along the anterior surface of what muscle?
quadratus lumborum
the lumbar plexus is composed of anterior rami of ____
L1-L4
nerves of the lumbar plexus pass through ____ after nerve roots exit the spine
psoas major
name the nerves of the lumbar plexus
- ilioinguinal & iliohypogastric nn (L1)
- genitofemoral n (L1-2)
- lateral femoral cutaneous n (L2-3)
- femoral n (L2-4)
- obturator n (L2-4)
- lumbosacral trunk (L4-5)
function of ilioinguinal & iliohypogastric nerves
sensory & motor to anterior abdominal wall mm
function of genitofemoral nerve
- sensory to upper medial thigh
- motor to cremaster m
function of lateral femoral cutaneous n
sensory to lateral upper thigh
function of femoral n
sensory & motor to ant thigh (quads)
function of obturator n
sensory & motor to medial thigh (adductors)
function of lumbosacral trunk
contribute to sacral plexus
sympathetic innervation of GI tract to left colic flexure
- greater splanchnic n (T5-9/10)
- lesser splanchnic n (T10-11)
- least splanchnic n (T12)
sympathetic innervation of left colic flexure to rectum
lumbar plexus (L1-3)
parasympathetic innervation of GI tract to left colic flexure
vagus n from vagal plexuses
parasympathetic innervation of left colic flexure to rectum
pelvic splanchnic nn (S2-S4)
spinal level of spleen innervation
T6-T8
spinal level of stomach, duodenum, liver, gallbladder, & pancreas innervation
T6-T9
spinal level of jejunum & ileum innervation
T8-T10
spinal level of suprarenal gland innervation
T6-L2
spinal level of kidney innervation
T10-L1
spinal level of cecum, appendix, & ascending colon innervation
T10
spinal level of transverse colon innervation
T11
spinal level of descending colon innervation
T12-L2
spinal level of sigmoid colon & rectum innervation
S2
the greater splanchnic nerve consists predominantly of ____ganglionic ____ fibers from ____
preganglionic sympathetic
T5-T10
Name all the organs which receive sympathetic innervation from the greater splanchnic nerve
- esophagus
- stomach
- liver
- left colic flexure
- small intestine, ascending colon, transverse colon
- duodenum
