Neurovasculature of Pelvis

Question 1

common iliac artery

Answer 1

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)

Question 2

Internal Iliac Artery

Answer 2

1 on each side of pelvis
common iliac artery
courses inferiorly over pelvic inlet
at the level of greater sciatic foramen

Question 3

anterior trunk

supply what structure?

Answer 3

pelvic viscera
perineum: erectile tissue
gluteal region

Question 4

posterior trunk

supply what structure

Answer 4

lower abdominal wall
posterior pelvic wall
gluteal region

Question 5

Posterior trunk branches

Answer 5

iliolumbar artery
lateral sacral arteries
superior gluteal artery

Question 6

iliolumbar artery

Answer 6

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

Question 7

lateral sacral arteries

Answer 7

course medially and inferiorly to posterior pelvic wall

supplies sacrum and skin of sacral region

Question 8

superior gluteal artery

Answer 8

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

Question 9

anterior trunk

Answer 9

umbilical artery 
superior vesical artery
inferior vesical 
vaginal artery 
uterine artery 
middle rectal artery 
obturator artery 
internal pudendal artery 
inferior gluteal artery

Question 10

umbilical artery

Answer 10

1st branch of anterior trunk
will give superior vesical
rest of vessel is obliterated: medial umbilical lig. (remnant of fetal circulation

Question 11

superior vesical

Answer 11

orginates from umbilical artery

supplies sup. bladder distal part of ureter

Question 12

inferior vesical artery

Answer 12

only in male

supplies bladder, ureter, serminal vesicle & prostate

Question 13

uterine artery

Answer 13

courses medially & anteriorly in broad ligament (transverse cervical ligament)
crosses ureter
reaches cervix region
supplies uterus ovary and vagina

Question 14

Vaginal artery

Answer 14

equivalent of inf. vesical artery in male
some time from uterine artery
supplies vagina, adjacent part of bladder and rectum

Question 15

middle rectal artery

Answer 15

course medially to supply the rectum

anastomose with sup. rectal artery from IMA and inferior rectal artery from internal pudendal of perineum )

Question 16

obturator artery

Answer 16

courses anteriorly along pelvic wall 
leaves pelvic cavity through obturator foramen
supplies medial (abductor) region of thighs

Question 17

internal pudendal artery

Answer 17

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

Question 18

inferior gluteal artery

Answer 18

terminal branch of internal iliac
passes between sacral nerve S2 + S3
leaves pelvic cavity through greater sciatic foramen inf. to piriformis
supplies gluteal region

Question 19

Veins

Answer 19

venous drainage– > interconnected venous plexuses-pelvic venou plexus
associated with organs
follow course of arteries, except illiolumbar and umbilical, no vein equivalent

Question 20

portosystemic anastomosis

Answer 20

superior rectal (IMV portal system) , middle rectal internal iliac (systemic) and inf rectal (internal pudendal, systemic)

Question 21

somatic innervation

Answer 21

sacral plexus
formed by ant rami of S1 to S4 + L4-L5
onto ant. surface of piriformis
nerves for lower limb, pelvis & perineum

Question 22

perineum

Answer 22

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

Question 23

pudendal block

Answer 23

anesthesia is performed near attachment of scrospinous ligament, ischial spine

Question 24

visceral innervation

Answer 24

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

Question 25

paravertebral sympathetic trunk

Answer 25

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)

Question 26

sacral nerve

Answer 26

postganglionic sympathetic fibre

Question 27

sacral splanchnic nerve

Answer 27

preganglionic sympathetic fibres to contribute to pelvic part of prevetebral plexus, inferior hypogastric plexus to viscera

Question 28

pelvic splanchnic nerve

Answer 28

orginate from S2-S4 anterior rami of sacral nerve

carry preganglionic parasympathetic fibres to inferior hypogastirc nerve

Question 29

parasympathetic effect

Answer 29

vasodilator
bladder contraction
erection
modulate hindgut activity

Question 30

sympathetic effect

Answer 30

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