Neurovasculature of Pelvis Flashcards
common iliac artery
originate from aortic bifurcation (L4) run inferolaterally, along medial aspect of psoas major ends over the sacro-illiac joint split into internal iliac artery external illiac artery (for limbs)
Internal Iliac Artery
1 on each side of pelvis
common iliac artery
courses inferiorly over pelvic inlet
at the level of greater sciatic foramen
anterior trunk
supply what structure?
pelvic viscera
perineum: erectile tissue
gluteal region
posterior trunk
supply what structure
lower abdominal wall
posterior pelvic wall
gluteal region
Posterior trunk branches
iliolumbar artery
lateral sacral arteries
superior gluteal artery
iliolumbar artery
ascends laterally out of the pelvic inlet
gives:
lumbar branches to post. abdominal wall
psoas, quadratus lumborum muscle)
iliac branch to iliac fossa for illiacus muscle and iliac bone
lateral sacral arteries
course medially and inferiorly to posterior pelvic wall
supplies sacrum and skin of sacral region
superior gluteal artery
largest branch of internal iliac artery: terminal branch
leaves the pelvic cavity through greater sciatic foramen above piriformis
supplies muscle and skin of gluteal region
anterior trunk
umbilical artery superior vesical artery inferior vesical vaginal artery uterine artery middle rectal artery obturator artery internal pudendal artery inferior gluteal artery
umbilical artery
1st branch of anterior trunk
will give superior vesical
rest of vessel is obliterated: medial umbilical lig. (remnant of fetal circulation
superior vesical
orginates from umbilical artery
supplies sup. bladder distal part of ureter
inferior vesical artery
only in male
supplies bladder, ureter, serminal vesicle & prostate
uterine artery
courses medially & anteriorly in broad ligament (transverse cervical ligament)
crosses ureter
reaches cervix region
supplies uterus ovary and vagina
Vaginal artery
equivalent of inf. vesical artery in male
some time from uterine artery
supplies vagina, adjacent part of bladder and rectum
middle rectal artery
course medially to supply the rectum
anastomose with sup. rectal artery from IMA and inferior rectal artery from internal pudendal of perineum )
obturator artery
courses anteriorly along pelvic wall leaves pelvic cavity through obturator foramen supplies medial (abductor) region of thighs
internal pudendal artery
courses inferior
leaves the pelvic cavity through greater sciatic foramen, inf to piriformis
passes lateral to ischial spine
then through lesser sciatic foramen to reach perineum
supplies erectile tissue of perineum, inferior rectum
inferior gluteal artery
terminal branch of internal iliac
passes between sacral nerve S2 + S3
leaves pelvic cavity through greater sciatic foramen inf. to piriformis
supplies gluteal region
Veins
venous drainage– > interconnected venous plexuses-pelvic venou plexus
associated with organs
follow course of arteries, except illiolumbar and umbilical, no vein equivalent
portosystemic anastomosis
superior rectal (IMV portal system) , middle rectal internal iliac (systemic) and inf rectal (internal pudendal, systemic)
somatic innervation
sacral plexus
formed by ant rami of S1 to S4 + L4-L5
onto ant. surface of piriformis
nerves for lower limb, pelvis & perineum
perineum
pudendal nerve: S2-3,4 motor sensory
leaves pelvic cavity through greater sciatic foramen
inf. to piriformis
pass around sacrospinous ligament, loop over ischial spine
through lesser sciatic foramen
reaches perineum with internal pudendal
pudendal block
anesthesia is performed near attachment of scrospinous ligament, ischial spine
visceral innervation
pelvic extension of superior hypogastric plexus
carry sympathetic and parasymp
enter pelvis via 2 hypogastric nerves, one on each side
will receive pelvic & sacrla splanchnic nerves to form inferior hypogastric plexus
located around pelvic wall & viscera
paravertebral sympathetic trunk
inferior end of sympathetic trunk in pelvic cavity
pass over sacrum, post to iliac vessels
run ant to sacrum
medial to sacral foramina
each trunk 4 ganglia on each side
join to form on terminal single ganglion (impar)
sacral nerve
postganglionic sympathetic fibre
sacral splanchnic nerve
preganglionic sympathetic fibres to contribute to pelvic part of prevetebral plexus, inferior hypogastric plexus to viscera
pelvic splanchnic nerve
orginate from S2-S4 anterior rami of sacral nerve
carry preganglionic parasympathetic fibres to inferior hypogastirc nerve
parasympathetic effect
vasodilator
bladder contraction
erection
modulate hindgut activity
sympathetic effect
innervate blood vessels
contraction of internal urethral sphincter
cause contraction of smooth muscle associate with reproductive tract, accessory gland
peristalsis for moving secretion of epididymus and associated glands during ejaculation
