unit 6: sacral plexus, posterior division & coccygeal plexus

Question 1

nerve carrying fibers from S1 & S2 to the piriformis

Answer 1

nerve to the piriformis

Question 2

nerve made of fibers from L4, L5, S1 and leaves the pelvis through the greater sciatic foramen superior to piriformis

Answer 2

superior gluteal nerve

Question 3

superior branches of the superior gluteal nerve supply the (2)

Answer 3

gluteus medius & minimus

Question 4

inferior branches of the superior gluteal nerve supply the (3)

Answer 4

gluteus medius
gluteus minimus
tensor fascia lata

Question 5

nerve carrying fibers from L4-S2 that leaves the pelvis thru the greater sciatic foramen inferior to piriformis

Answer 5

inferior gluteal nerve

Question 6

muscle innervated by inferior gluteal nerve

Answer 6

gluteus maximus

Question 7

nerve containing fibers from S2 & S3 named for traveling through the sacrotuberous ligament, ultimately lending sensory to lower medial aspects of buttocks
-may be absent or formed by branch off of pudendal

Answer 7

perforating cutaneous nerve

Question 8

two nerves formed by branches of both anterior and posterior divisions of the sacral plexus

Answer 8

posterior cutaneous nerve of the thigh

sciatic nerve

Question 9

the posterior cutaneous nerve of the thigh is formed by fibers from the ANT divisions of __&__ and the POST divisions of __&__

Answer 9

S2 & S3

S1 & S2

Question 10

the posterior cutaneous nerve of the thigh leaves the pelvis thru the __ __ foramen, descends thru post thigh and inferior to leg where it ultimately communicates with the __ nerve

Answer 10

greater sciatic

sural

Question 11

the posterior cutaneous nerve of the thigh supplies skin on the

Answer 11

posterior and medial thigh

Question 12

the __ nerve is the largest in the human body and is a combination of the medial ___ nerve from the ANT L4-S3 and the lateral __ __ nerve from the POST L4-S2

Answer 12

sciatic
tibial
common fibular

Question 13

• the sciatic nerve leaves the pelvis thru the ___ ___ foramen below piriformis, inf to the post aspect of __ __
• usually splits approx 2/3 way to the knee (varies)

Answer 13

greater sciatic

adductor magnus

Question 14

one muscle supplied by the common fibular nerve in the thigh before sep from tibial nerve fibers

Answer 14

biceps femoris (short head)

Question 15

common fib nerve courses around lat aspect of fibula; at the antero-lateral aspect of the leg, it sends an ARTICULAR branch to the

Answer 15

knee joint

Question 16

two sensory branches of the common fib nerve along the lateral aspect of popliteal fossa

Answer 16

lateral sural cutaneous nerve

fibular communicating branch

Question 17

of the two sensory branches off the common fib, the ________ nerve supplies the skin on the lateral leg, while the ____ branch forms the sural n. after combining with the medial sural cutaneous n.

Answer 17

lateral sural cutaneous

fibular communicating

Question 18

branch off common fibular that travels inf bt the fibularis longus and fibula down to the dorsum of the foot

Answer 18

superficial fibular nerve

Question 19

two muscles supplied by the superficial fibular nerve

Answer 19

fibularis longus

fibularis brevis

Question 20

after supplying its muscles, the superficial fibular nerve splits into these TWO nerves, which combine to supply skin over the DORSUM of foot (not skin bt first 2 toes)

Answer 20

medial dorsal cutaneous nerve

intermediate dorsal cutaneous nerve

Question 21

branch off common fib that is primarily muscular for the anterior compartment (extensors), but does have a terminal branch that is sensory to the skin bt the first 2 toes

Answer 21

deep fibular nerve

Question 22

tibialis anterior
extensor digitorum longus & brevis
extensor hallicus longus & brevis
fibularis tertius
--are all extensors of the foot and are supplied by

Answer 22

deep fibular nerve

Question 23

four muscles supplied by the tibial while still combined with the common fib

Answer 23

biceps femoris (long head)
semitendinosus
semimembranosus
adductor magnus

Question 24

in the popliteal fossa, the tibial nerve gives off articular branches to the knee, a popliteal branch, and muscular branches to these 4 muscles

Answer 24

popliteus
gastrocnemius
soleus
plantaris

Question 25

in the popliteal fossa, the tibial nerve gives off the ___ branch that travels inf to give rise to the _________

Answer 25

popliteal | interosseous nerve of the leg

Question 26

the interosseous nerve of the leg continues inferior along the post surface of the interosseous membrane and carries sens info from the:

Answer 26

tibial periosteum ankle tibiofibular joints

Question 27

once in the LEG, the tibial nerve gives off muscular branches to supply these 2 muscles

Answer 27

flexor digitorum longus | flexor hallucis longus

Question 28

in the LEG, these sensory branches come off the tibial nerve to supply the skin of the the medial heel

Answer 28

medial calcaneal branches

Question 29

two terminal branches given off the tibial after it travels around the med malleolus to the plantar surface of the foot

Answer 29

medial & lateral plantar nerves

Question 30

three muscles supplied by the medial plantar nerve

Answer 30

abductor hallucis flexor digitorum brevis flexor hallucis brevis

Question 31

the medial plantar nerve further divides into these nerves, which send motor supply to lumbricals 1 & 2

Answer 31

common plantar digital nerves

Question 32

sensory supply to skin bt toes occurs off the common plantar digital nerves by way of the

Answer 32

proper plantar digital nerves

Question 33

the lateral plantar nerve divides into a ____ branch supplying the skin around digit 5 and a ___ branch which supplies 4 muscles

Answer 33

superficial | deep

Question 34

four muscles supplied by the deep branch of the lateral plantar nerve

Answer 34

adductor halluces flexor digiti minimi brevis lateral lumbricals interossei muscles

Question 35

the coccygeal plexus is formed by the APR of __, __ & __ nerves

Answer 35

s4 s5 co1

Question 36

the coccygeal plexus nerves combine to become the ____ nerves that carry sensory info from the skin adjacent to the coccyx & anus

Answer 36

anococcygeal