lower extremity innervation 12/30

Question 1

lumbar plexus

Answer 1

psoas major, minor

quadratus lumborum

Question 2

sacral plexus

Answer 2

• piriformis
• triceps coxae: superior gemelli, inferior gemelli, obturator internus
• quadratus femoris

Question 3

inferior gluteal n

Answer 3

gluteus maximus

Question 4

superior gluteal n

Answer 4

glute medius
glute minimus
tensor fasciae latae

Question 5

femoral n

Answer 5

rectus femoris
vastus lateralis, medialis, intermedius
iliacus
pectineus
sartorius

Question 6

obturator n

Answer 6

adductor longus, brevis, magnus
obturator externus
gracilis

Question 7

tibial n

Answer 7

plantarflexors: gastrocnemius, soleus
popliteus
plantaris
tibialis posterior
flexor hallucis longus
flexor digitorum longus

Question 8

sciatic nerve - tibial division

Answer 8

hamstrings: semitendinosus, semimembranosus, biceps femoris (long head)

Question 9

sciatic nerve - common peroneal division

Answer 9

biceps femoris (short head)

Question 10

deep peroneal n

Answer 10

(dorsiflexors, anterior compartment lower leg)
tibialis anterior
peroneus tertius
extensor hallucis longus
extensor digitorum longus
extensor digitorum brevis

Question 11

superficial peroneal n

Answer 11

(evertors, lateral lower leg)
peroneus longus
peroneus brevis

Question 12

medial plantar n

Answer 12

abductor hallucis
flexor hallucis brevis
flexor digitorum brevis
lumbrical 1

Question 13

lateral plantar n

Answer 13

• (pinky toe) abductor digiti minimi, flexor digiti minimi, opponens digiti minimi
• adductor hallucis
• lumbrical 2,3,4
• Interossei: dorsal interossei, plantar interossei
• quadratus plantae

Question 14

common causes of femoral nerve damage

Answer 14

• direct trauma - pelvic fractures
• prolonged pressure, compression, stretching, entrapment - large heavy belts, catheter in femoral artery, internal bleeding in pelvis or abdomen, lying on bath with legs flexed during surgery
• diabetes, other causes of peripheral neuropathy

Question 15

what muscle is innervated by the obturator nerve in <10% of individuals, while most often it is innervated by the femoral nerve.?

Answer 15

pectineus

Question 16

what muscle is innervated by the anterior division of the obturator nerve (L2-L4)

Answer 16

adductor longus

Question 17

Which nerve innervates the cremasteric muscle?

Answer 17

genitofemoral nerve - genital branch, genitofemoral nerve arises from the roots of L1 and L2

Question 18

what motion is affected by lesion of dorsal nerve root of C7?

Answer 18

elbow extension, wrist flexion