Innervation and Actions of mms of Lower Leg and Foot

Question 1

tibialis anterior (TA)

Answer 1

act: dorsiflexes at ankle jt and inverts foot at the subtalar and transverse tarsal jts
n: deep peroneal n

Question 2

extensor digitorum longus (EDL)

Answer 2

act: extends toes at MTPs and IP jts, dorsiflexion of ankle and eversion at the subtalar and transverse tarsal jts
n: deep peroneal

Question 3

extensor hallucis longus (EHL)

Answer 3

act: extends great toe at the MTP and IP jts, assists w/ dorsiflexion at ankle and inversion of foot at subtalar and transverse tarsal jts
n: deep peroneal n

Question 4

fibularis tertius (peroneus tertius)

Answer 4

act: dorsiflex at ankle and everts at the subtalar and transverse tarsal jts
n: deep peroneal

Question 5

fibularis longus (peroneus longus)

Answer 5

act: everts foot at the subtalar and transverse tarsal jts and assists w/ plantarflexion at ankle
n: superficial peroneal n

Question 6

fibularis brevis (peroneus brevis)

Answer 6

act: everts foot at subtalar and transverse tarsal jts and assists w/ plantarflexion at the ankle jt
n: superficial peroneal n

Question 7

plantaris

Answer 7

act: assist plantarflexion at ankle and assists FLEX at knee
n: tibial n

Question 8

gastrocnemius

Answer 8

act: plantarflexion of ankle and assists w/ FLEX at knee
n: tibial n

Question 9

soleus

Answer 9

act: plantarflexion of ankle
n: tibial n

Question 10

popliteus

Answer 10

act: MED ROTs tibia on femur when origin is fixed, when standing LAT ROTs femur on tibia thus helping unlock knee
n: tibial n

Question 11

flexor digitorum longus (FDL)

Answer 11

act: flexes toes at MTP and IP jts, assists w/ plantar FLEX at ankle jt and inversion at the subtalar and transverse tarsal jts
n: tibial n

Question 12

flexor hallucis longus (FHL)

Answer 12

act: flexes big toe at MTP and IP jts, assists w/ plantarflexion at ankle and inversion at subtalar
n: tibial n

Question 13

tibialis posterior (TP)

Answer 13

act: inversion of foot at subtalar and transverse tarsal jts and assists w/ plantarflexion at the ankle
n: tibial n

Question 14

extensor digitorum brevis

Answer 14

act: extends digits 2, 3, 4 at the IP and MTP jts
n: deep peroneal (fibular)

Question 15

extensor hallucis brevis

Answer 15

act: extends big toe at MTP jt
n: deep peroneal

Question 16

abd hallucis

Answer 16

act: abd and flexes big toe at MTP jt
n: MED plantar

Question 17

flexor digitorum brevis

Answer 17

act: flexes digits 2-5 at the PIP and the MTP jts
n: MED plantar

Question 18

abd digiti minimi (brevis)

Answer 18

act: abd 5th at MTP and assists w/ FLEX
n: LAT plantar

Question 19

quadratus plantae

Answer 19

act: flexes digits 2-5 (assisting FDL at all jts)
n: LAT plantar

Question 20

lumbricales (4)

Answer 20

act: flexes MTP jt and extends PIP and DIP jt of digits 2-5 (flattens toes)
n: 1st lumb- MED plantar, 2-4 lumb- LAT plantar

Question 21

flexor hallucis brevis

Answer 21

act: flexes MTP jt of big toe
n: MED plantar

Question 22

adductor hallucis (2 HDs)

Answer 22

act: adducts big toe
n: deep branch of LAT plantar

Question 23

flexor digiti minimi (brevis)

Answer 23

act: flexes MTP jt of the 5th
n: superficial branch of LAT plantar

Question 24

dorsal interossei (4)

Answer 24

act: DAB, abd and flex of the MTP jts and EXT at the DIP and PIP jts of digits 2-4
n: superficial and deep branches of the LAT plantar nerves

Question 25

plantar interossei (3)

Answer 25

act: PAD, add and flex of the MTP jts and ext at the DIP and PIP jts of toes 3-5
n: superficial and deep branches of LAT plantar nerves