Posterior Abdominal Wall Flashcards
What’s the muscular floor of the posterior abdominal wall?
Psoas Major and Minor
Iliacus
Quadratus Lumborum
Diaphragm
Psoas major + Minor?
where does psoas major come from?
what does psoas major do?
inserts to?
psoas major is the thick muscle going inferior to superior. Psoas minor is laying right on top of it.
psoas major comes from attaches to the transverse processes and vertebrae of T12 through lumbar vertebrae
major hip flexor, flexion of vertebral column and lateral bending of the vertebral column
the lesser trochanter
Where is the Iliacus found?
what does this merge with to form the iliopsoas?
what movements?
iliac fossa
Iliacus + psoas = iliopsoas
hip flexor and stabilize the hip.
Quadratus Lumborum?
attached to the 12th rib and the iliac crest
helps with posture and aids in lateral bending
what does the diaphragm do?
inspiration.
When you’re doing sit ups, what muscle are you working?
hip flexors.
Psoas abcess?
symptoms? (5)
what kinds of people are affected? (3)
what sign are you looking for?
infection deep to the psoas fascia (between the fascia and the muscle)
1) back / flank pain (because its on the posterior wall)..
2) fever (because infection), can show as an inguinal mass because it inserts on lesser trochanter (so may think it’s a hernia)
3) limp (limping because it compresses the fascia and hurts)
4) anorexia, weight loss
you see it where tuberculosis is endemic –>(especially with refugees + American Indian locations)
So going through the lungs into the blood stream –> vertebral bodies –> since psoas attaches to vertebral bodies it’s easy for it to go in and cause one
Fascial ligaments of the posterior abdominal wall??
Median Arcuate Ligament: goes right over the aorta (as the aorta enters through the hiatus of the diaphragm, that’s where we’ll see it
medial arcuate ligament = fascial thickening of the psoas major.
Lateral arcuate ligament: fascia over the quadratus lumborum muscle.
what ligaments do the diaphragm attach to?
medial and lateral arcuate ligament
What are the 3 parts of the muscular diaphragm?
where did the muscular diaphragm come from embryologically?
where did those come from?
Sternal (attaches to xiphoid)
Costal (attaches to the inferior 6 costal cartilages)
Lumbar (attaches to medial and lateral arcuate ligament)
abdominal wall –> hypomere
What else are you going to see on the diaphragm?
embryologically where did each come from?
central tendon –> septum transversum
Crura = right and left crus –> came from dorsal mesentery of the esophagus
right crus is larger and longer (L3-L4).. it comes up, circles the esophagus and comes back down. (creating the esophageal hiatus) (happens in 70% of people)
Left crus = L2-L3 (shorter)
What are the 3 apertures of the diaphragm? where are each located? What goes through each?
Caval opening –> located at T8.. this is where the IVC and Rt phrenic n. goes through (left phrenic pierces the diaphragm)
Esophageal Hiatus: Located at T10, esophagus, ant/post vagal trunks… also the esophageal arteries pass through this (from left gastric)
aortic hiatus: located at T12, aorta, thoracic duct, and sometimes the azygos and hemiazygos
Adrenal glands are found where?
what are they covered in?
Right suprarenal gland relationships?
what is the left suprarenal gland relationships?
between the diaphragm and the kidneys.
they’re covered in renal fascia and this is attaching them to the right crus or the left crus (right adrenal gland = attached to right crus)
Inferior = kidney superior and posterior = diaphragm posterior = right crus lateral to = IVC Anterior/medial = Liver
inferior = kidney
superior and posterior = diaphragm
anterior = spleen, stomach, pancreas
posterior = left crus
Blood supply for the adrenal glands? where do they come off from?
arteries and veins
superior suprarenal arteries ==> coming off of the inferior phrenic A.
middle suprarenal arteries ==> come from the aorta directly
inferior suprarenal arteries ==> coming from the renal arteries.
Veins ==> hormones need to get into the blood stream.
Right suprarenal right suprarenal vein –> goes into the IVC
left suprarenal vein –> drains into the left renal v.
Innervation of the adrenal glands?
preganglionic sympathetics from T6-L2 that supply the adrenal gland.
where is the postganglionic sympathetics located?
in the renal gland, NOT the suprarenal gland.
What kidney sits higher? where do they sit?
left side (T12 - L3)
right side is lower because of the liver (1/2 inch) below that.
posterior to the right and left kidneys?
what nerves would the kidneys also have posterior?
muscular floor –> including:
Psoas major muscle
quadratus lumborum, transversus abdominus
also the diaphragm
branches of L1 ilioinguinal and hypogastric and the subcostal nerve.
anterior to the right kidney?
liver, duodenum, ascending colon
anterior to the left kidney?
stomach, spleen, pancreas, jejunum, descending colon
What covers the kidney?
what muscles are medial or lateral to the kidney?
perinephric fat (directly) then fascia, then paranephric fat, then the muscles..
medial to the kidney = psoas major, lateral = anterior abdominal muscles
posterior = quadratus lumborum
what do we do for a kidney transplant.. do we do anterior or posterior?
posterior wall
Hilum of the kidney is located where?
what’s the most anterior structure of the hilum?
posterior to that?
posterior to that?
transpyloric plane (L1)
renal vein
renal artery
renal pelvis
What are the posterior relationships to the ureter?
why is this clinically relevant?
posterior to the ductus (vas) deferens for the male
also posterior to the uterine artery (female)
if you do a hysterectomy and you think you ligated the uterine a artery but ligate the ureter you have caused a kidney problem.
What are the 3 constriction points of the ureter (for a kidney stone)
ureteropelvic junction (renal pelvis to ureter)
crossing external iliac artery and/or pelvic brim
ureter enters the bladder wall.
If you have an organ from the foregut, they’re going to drain via the what?
midgut?
hindgut structures?
after starting at these, where do they go?
celiac.
Superior mesenteric lymph nodes
inferior mesenteric lymph nodes
go to the lumbar –> cisterna chyli –> thoracic duct
all lymphatic stuff from the abdomen and lower limbs goes where?
where is the cisterna chyli located?
eventually to the cisterna chyli (dilated structure at the very end of the thoracic duct) –> thoracic duct
L1ish level
What covers a lot of the lumbar plexus?
psoas major m.
what nerves are lateral to psoas major?
T12 = subcostal n (inferior to the 12th rib)
L1 splits into 2 = iliohypogastric is the more superior, ilioinguinal is inferior.
these 2 will pierce transverses abdomens around the ASIS to go between TA and IO… that’s where we lose contact with them.
the next is lateral cutaneous nerve of the. thigh –> this one dives deep to the inguinal ligament just medial to the ASIS
Femoral Nerve (HUGE) –> slightly under and lateral to psoas major.
Nerve running anterior to psoas major?
running anterior to psoas major is genitofemoral N.
Nerves running medial to psoas major?
Obturator N.
Lumbosacral trunks (lying on the ala.. this is the deepest nerves to see.
function of iliohypogastric
sensation and innervating internal oblique and transverses abdominus..
posterolateral gluteal skin and pubic region sensation
Obturator?
medial thigh sensory
motor = adductors (obturator externes, pectiques, muscles in medial thigh)
Femoral N innervation?
Anterior thigh and medial leg. (sensory)
innervating the hip flexors (anterior medial thigh) and quads
lumbosacral trunk gives rise to what?
sciatic.
How can lower abdominal pain be worsened to see if you have a psoas abscess?
Psoas sign – muscle contraction (extending) and irritating that sign.
you extend the affected side, it puts pressure on that area. so the pt will want to put it in flexion to relax it.
from the renal pelvis, what does it branch into and what are the structures?
renal pelvis –> major calyx –> minor calyx –> renal papilla –> goes into renal pyramids surrounded by renal cortex for the walls and renal columns separating the pyramids from one another
Ilioinguinal motor and sensory function?
motor = internal oblique and TA
sensory = skin of upper medial thigh, over anterior scrotum or labium majora
genitofemoral motor and sensory
motor = genital branch = male cremasteric muscle
sensory = genital branch = skin of anterior scrotum or labium majora = femoral branch = skin of upper anterior thigh
lateral cutaneous nerve sensory?
skin on anterior and lateral thigh to the knee
