Nerves of the pelvis (Sacral plexus, Autonomic)

Question 1

Formation of Sacral plexus

Answer 1

• Lumbosacral trunk =lower L4 ventral Rami + (all of) L5 Ventral rami
• Lumbosacral trunk + S1,S2,S3 ventral rami + upper part S4 ventral rami

Question 2

Upper part L4 ventral rami shares in formation of ____, Lower part of S4 ventral rami shares in formation of ____, therefore they are called ____

Answer 2

• Lumbar plexus
• Coccygeal plexus
• Nervus Furcalis

Question 3

Enumerate branches of Sacral plexus with thier root value

Answer 3

L4,L5,S1 = Superior gluteal N & N. to quadratus femoris

L5,S1,S2 = Inferior gluteal N & N. to obtrurator internus

S1,2 = N. to piriformis

S1,2,3 = posterior cutaneous N of thigh

S2,3 = Perforating Cutaneous N

S2,3,4 = Pelvic splanchnic N & Pudendal N

L4,L5,S1,S2,S3 = Sciatic Nerve

if all the roots begin with S, Branch must begin with P

Question 4

Root value of Sup. gluteal N

Answer 4

L4,L5,S1

(with N to quadratus)

Question 5

Root value of Inferior gluteal N

Answer 5

L5,S1,S2

(with N to obturator internus)

Question 6

Root value of Nerve to Quadratus femoris

Answer 6

S4,S5,L1

(with sup. gluteal N)

Question 7

Root value of Nerve to obturator internus

Answer 7

L5,S1,S2

(with inf gluteal N)

Question 8

Root value of Nerve to Piriformis

Answer 8

S1,S2

Question 9

Root value of Posterior cutaneous N of thigh

Answer 9

S1,S2,S3

Question 10

Root value of Perforating cutaneous N

Answer 10

S2,3

Question 11

Root value of Pudendal N

Answer 11

S2,S3,S4

(with Pelvic Splanchnic N)

Question 12

Root value of Pelvic Splanchnic N

Answer 12

S2,S3,S4

(with Pudendal N)

Question 13

Root value of Sciatic N

Answer 13

L4,L5,S1,S2,S3

all except S4

Question 14

Site of Pelvic sympathetic chain

Answer 14

Infront of sacrum, Anterior or medial to Anterior sacral foramina

Question 15

Ending of Pelvic sympathetic chain

Answer 15

both chain unite in front of coccyx, forming Ganglion Impar

Question 16

Lateral branches of Pelvic sympathetic chain give:

Answer 16

Communicating to Sacral & coccygeal Nerves

Question 17

Medial branches of Pelvic sympathetic chain give:

Answer 17

join inferior hypogastric plexus (from upper 2 ganglia)

Question 18

Site of Superior Hypogastric plexus

Answer 18

Below aortic bifrication in front of L5 vertebra

Question 19

Formation of superior hypogastric plexus

Answer 19

Sympathetic:
* aortic sympathetic plexus
* 3rd & 4th Lumbar splanchnic Nerves

Parasympathetic: Pelvic parasympathetic fibers

Question 20

branches of Superior hypogastric plexus

Answer 20

• Inferior mesenteric
• Gonadal
• Ureteric
• Common iliac
• Hypogastric nerve –> share in formation of Inferior hypogastric plexus

Question 21

Site of (Rt & Lt) inferior hypogastric plexus

Answer 21

Medial to Internal iliac vessels

Question 22

Formation of Inferior hypogastric plexus

Answer 22

• Right & Left Hypogastric from superior hypogastric plexus
• Branches of the first 2 ganglia of Pelvic symapthetic chain
• Parasympathetic from pelvic splanchnic S2,3,4)

Question 23

Branches of Inferior hypogastric plexuses supplies:

Answer 23

Pelvic viscera