Pelvic Nerves and Vessels Flashcards
What is the root value of the sacral plexus
L4-S5
What is the largest nerve coming from the sacral plexus, and what is its root value
The sciatic nerve, and L4-S3
What area does the sciatic nerve supply
It supplies motor and sensory innervation to the posterior compartment of the thigh, and the leg and foot
How many gluteal nerves do we have; name them
2; superior and inferior gluteal nerves
What is the root value of the gluteal nerves
Superior = L4-S1 Inferior = L5-S2
What muscle is in between the gluteal nerves
Piriformis
Which gluteal muscles are supplied by which nerve
Superior = gluteus medius and minimus Inferior = gluteus maximus
What is the root value of the nerve to obturator internus
L5-S2
What muscles does the nerve to obturator internus supply
Obturator internus and superior gamellus
What is the root value of the nerve to piriformis
S1-S2
What is the root value of the pudendal nerve
S2-S4
What are the 5 main structures that are supplied by the pudendal nerve
- Levator ani
- External anal sphincter
- External urethral sphincter
- Bulbospongiosus
- Ischiocavernosus
What is the root value of the nerve to levator ani
S4
What is the root value of the nerve to coccygeus
S4-S5
What autonomic plexus’ innervate the pelvic region
Superior hypogastric plexus (x1)
Inferior hypogastric plexus (x2)
What is the root value of the pelvic splanchnic nerve
S2-S4
Where is the superior hypogastric plexus located
Close to the bifurcation of the abdominal aorta
Describe 3 examples of sympathetic innervation in the pelvis
- Contraction of the internal anal and urethral sphincters
- Relax the detrusor muscle of the bladder
- During ejaculation, contraction of the vas deferens and seminal vesicles
Describe 3 examples of parasympathetic innervation in the pelvis
- Increase motility of the rectum and anal canal
- Vasodilation of the arteries of the penis; during erection
- Relax the internal anal and urethral sphincters
Describe where the S1 dermatome is
Posterior surface of the heel and the plantar surface of the foot
Describe where the S2 dermatome is
It runs down the posterior surface of the thigh
At what level does the abdominal aorta bifurcate, and what arises
At L4, and the 2 common iliacs arise
What do the internal iliacs divide further into
Anterior and posterior branches
Name the 6 main arteries that branch from the anterior division of the internal iliac artery
- Umbilical artery; gives rise to superior vesical
- Obturator
- Inferior vesical
- Middle rectal
- Internal pudendal
- Inferior gluteal
In males, what branch does the inferior vesical artery give rise to
The prostatic artery
Is the inferior vesical artery present in females
No
What artery is present in females instead of the inferior vesical; and what does it give rise to
Uterine artery; gives rise to the vaginal artery
Name the 3 main arteries that branch from the posterior division of the internal iliac
- Iliolumbar
- Lateral sacral
- Superior gluteal
What viscera receive their blood supply directly from the abdomen
Testes in males, and ovaries in females
What vessel does the majority of blood from the pelvis drain to
The internal iliac vein; common iliac vein; IVC
