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