B6.032 Prework 3: Lumbosacral plexus and peripheral nerves

Question 1

lumbar plexus roots

Answer 1

L2-L4

Question 2

major branches off of lumbar plexus

Answer 2

lateral femoral cutaneous
femoral
obturator

Question 3

innervation of lumbar plexus

Answer 3

motor and sensory contributions to the anterior and medial compartments of the leg

Question 4

sacral plexus roots

Answer 4

L4-S4

Question 5

major branches off of sacral plexus

Answer 5

superior gluteal
inferior gluteal
sciatic (peroneal + tibial)
Pudendal

Question 6

superior gluteal nerve

Answer 6

gluteal minimus, medius muscles

hip adductor

Question 7

inferior gluteal nerve

Answer 7

gluteal maximum

hip extendor

Question 8

innervation of sacral plexus

Answer 8

motor and sensory contributions to gluteal and parts of pelvic region, posterior thigh, most of lower leg, and entire foot

Question 9

sciatic nerve roots

Answer 9

L4-S3

longest and largest in the body

Question 10

clinical implication of sciatic nerve

Answer 10

tight piriformis muscle can cause compression of sciatic nerve and give posterior leg symptoms of pain and paresthesia
mimics symptoms of sacral nerve root compression

Question 11

innervation of sciatic nerve

Answer 11

semitendinosis
semimembranosus
biceps femoris
adductor magnus

Question 12

branches of sciatic nerve

Answer 12

tibial nerve

common peroneal nerve

Question 13

innervation of tibial nerve

Answer 13

gastrocnemius
plantaris soleus
popliteus
tibialis posterior
flexor digitorum longus
flexor hallucis longus
*ankle and toe flexion*

Question 14

innervation of sural nerve

Answer 14

sensation to posterior lateral aspect of the lower 1/3 leg and lateral foot

Question 15

medial and lateral plantar nerve

Answer 15

motor and sensory innervation to the plantar foot

Question 16

what is the peroneal nerve

Answer 16

common fibular nerve

travels to upper lateral portion of the lower leg and wraps around the fibular head

Question 17

clinical implication of peroneal nerve

Answer 17

common peroneal neuropathy > foot drop

Question 18

innervation of peroneal nerve

Answer 18

ankle dorsiflexion

toe extension

Question 19

innervation of superficial peroneal nerve

Answer 19

peroneus longus and brevis

sensory distribution to anterior lateral lower leg and dorsum of foot

Question 20

innervation of deep peroneal nerve

Answer 20

innervates tibialis anterior, ext dig longus, peroneus tertius

Question 21

clinical implication of gluteal innervation

Answer 21

superior gluteal nerve injury leads to opposite pelvis drop

Trendelenburg gait

Question 22

lateral femoral cutaneous neuropathy

Answer 22

from wearing heavy tool belts and compressing lateral inguinal area
sensory loss to lateral thigh

Question 23

saphenous nerve entrapment

Answer 23

from medial knee surgery/injury

pain medial distal knee

Question 24

sural nerve entrapment

Answer 24

recurrent ankle problems

pain posterior lateral lower 1/3 leg or lateral foot