Muscles of the Leg, Ankle and Foot - Actions

Question 1

Popliteus

Answer 1

Medially rotates the leg relative to the femur.
Unlocks the terminally locked knee at the first stage of knee flexion from full extension

*small Ma for knee flexion

Question 2

Gastrocnemius

Answer 2

Flexes the ankle (plantar flex)
Weak knee flexor
Cannot evert or invert the foot

Question 3

Soleus

Answer 3

Flexes the ankle (plantar flex)

Cannot evert or invert the foot

Question 4

Tibialis posterior

Answer 4

Plantar flexes and inverts the foot

Dynamically supports the medial longitudinal arch of the foot

Question 5

Flexor digitorum longus

Answer 5

Flexes digits 2-5

Small moment arm for plantar flexion and inversion of the ankle

Question 6

Flexor hallucis longus

Answer 6

Flexes 1st digit

Question 7

Fibularis longus

Answer 7

Everts the foot

Moment arm for plantar flexion

Question 8

Fibularis Brevis

Answer 8

Everts the foot

Moment arm for plantar flexion

Question 9

Tibialis posterior

Answer 9

Dorsiflexes the ankle
Inverts the foot
Assists in maintaining the medial longitudinal arch of the foot

Question 10

Extensor hallucis longus

Answer 10

Extends the big toe (1st digit)

Dorsiflexes the ankle

Question 11

Extensor digitorum longus

Answer 11

Extends digit 2-4
Dorsiflexes the ankle
Weak eversion

Question 12

Fibularis tertius

Answer 12

Dorsiflex the ankle

Everts the foot

Question 13

Plantar Interossei

Answer 13

Adducts digits 3-4 at the metatarsophalangeal joints

Question 14

Dorsal Interossei

Answer 14

Abducts digits 2-4 at the metatarsophalangeal joints

Question 15

Flexor Digiti Minimi

Answer 15

Flexes the 5th digit at the metatarsophalangeal joint

Question 16

Flexor Hallucis Brevis

Answer 16

Flexes the big toe at the metatarsophalangeal joint

Question 17

Quadratus Plantae

Answer 17

Assists in toe flexion

Question 18

Lumbricals

Answer 18

Abduction and flexion of the toes at the metatarsophalangeal joint

Extension of digits 2-5 at proximal interphalangeal and distal interphalangeal joints

Question 19

Abductor Digiti Minimi

Answer 19

Abduction and flexion of the 5th digit at the metatarsophalangeal joint

Question 20

Flexor Digitorum Brevis

Answer 20

Flexion of the toes at the metatarsophalangeal joint

Question 21

Abductor Hallucis Brevis

Answer 21

Abduction and flexion of the big toe at the metatarsophalangeal joint

Question 22

Extensor Hallucis Brevis

Answer 22

Extends the hallux (1st digit) at the metatarsophalangeal joint

Question 23

Extensor Digitorum Brevis

Answer 23

Extends digit 2-4 at the metatarsophalangeal joint