Flashcards in Pelvis Neurovasculature Deck (35):
What are the divisions of the internal iliac artery?
Anterior and posterior
Briefly describe the course of the superior gluteal arteries
Run posteriorly between lumbosacral trunk and S1, then exit pelvis via greater sciatic foramen superior to piriformis muscle
Give the rule of pelvic venous drainage and two exceptions to that rule
Rule - Internal Iliacs to Common Iliacs to IVC. Exception 1 - Lateral sacral veins to Internal vertebral venous plexuses. Exception 2 - Superior rectal veins to portal system.
Four main types of pelvic lymph nodes
External iliac, internal iliac, sacral, common iliac
What do each of the four types of pelvic lymph nodes drain?
Sacral - Posteroinferior pelvic viscera, External Iliac - Pelvic viscera, inguinal nodes, Internal Iliac - Inferior pelvic viscera, deep perineum, gluteal region, Common iliac - Inferior structures drain up to them and they drain to lumbar (caval/aortic) nodes
What cutaneous nerve innervates the largest skin area of any in the body?
The posterior femoral cutaneous nerve (S1-S3)
Innervation of quadratus femoris and inferior gamellus
L4-S1 via sacral plexus
Innervation of obturator internus and superior gamellus
L5-S2 via sacral plexus
Innervation of piriformis muscle
S1-S2 via sacral plexus
Where does the obturator nerve originate and where does it go?
Originates in lumbar plexus (L2-L4) and goes to medial thigh
Where does the obturator nerve pass through the pelvis?
On the pelvic sidewall and out the obturator foramen
4 main types of pelvic autonomic nerves
Sacral sympathetic trunks, periarterial plexuses, hypogastric plexuses, pelvic splanchnic nerves
Where do the sacral sympathetic trunks run relative to the pelvic foramina?
Medial to the foramina
How many ganglia do the sacral sympathetic trunks usually have?
A structure formed by the convergence of 2 ganglia of the pelvic sympathetic trunk
Periarterial nervous plexuses of the pelvis run with which arteries?
Superior rectal, ovarian, internal iliac
What is the function of periarterial nervous plexuses of the pelvis?
Vasomotion of the arteries
What do pelvic splanchnic nerves carry (include fiber type, system, post/presynaptic, and origin)?
Presynaptic parasympathetic GVA fibers from S2, S3 and S4
Where are the superior hypogastric plexuses and what are they formed from?
Just inferior to bifurcation of the aorta, formed as continuation of intermesenteric and inferior mesenteric plexuses
What fibers are carried by the superior hypogastric plexus?
GVA Postsynaptic sympathetic nerve fibers
What plexuses are supplied by the superior hypogastric plexuses?
Ureteric and testicular plexuses
Are the superior hypogastric and inferior hypogastric plexuses connected and if so by what?
Yes, by the right and left hypogastric nerves
Generally speaking, the inferior hypogastric plexuses provide what type of innervation to where?
Autonomic innervation to the pelvic viscera
Nerves of the inferior hypogastric plexuses spread and join with what?
Pelvic splanchnic nerves
Generally speaking, where are sympathetic and parasympathetic fibers relayed through the pelvic plexuses?
Sympathetic fibers via the hypogastric plexuses, parasympathetic fibers via the pelvic splanchnic nerves
List the purely sympathetic components of the pelvis
1) Aortic/intermesenteric plexuses, 2) Sacral splanchnic nerves, 3) Ganglion impar, 4) Internal Iliac periarterial plexuses, 5) Sacral/lumbar sympathetic trunks, 6) Left/Right hypogastric nerves, 7) Superior hypogastric plexus, 8) Inferior mesenteric/superior rectal periarterial plexuses
List the purely parasympathetic components of the pelvis
Pelvic splanchnic nerves
List the mixed autonomic components of the pelvis
Inferior hypogastric plexuses, ovarian periarterial plexuses
List the somatic components of the pelvis
Pudendal nerve, sciatic nerve
What do sympathetic fibers of the pelvis do?
Produce vasomotion, contraction of internal genital organs during orgasm, inhibit rectal peristalsis
What do parasympathetic fibers of the pelvis do?
Stimulate bladder and rectal emptying, extend to the erectile bodies of external genitalia to produce erection
What do visceral afferent fibers of the pelvis convey and to where do they convey it?
Unconscious reflex sensation to spinal sensory ganglia of S2-S4
Where is the pelvic pain line?
Inferior limit of the peritoneum
What do visceral afferent fibers follow superior to the pelvic pain line?