Leg Muscles

Question 1

Tibialis anterior origin

Answer 1

Upper 2/3 of lateral surface of the tibia, interosseous membrane, and superficial crural fascia of leg

Question 2

Tibialis anterior insertion

Answer 2

Medial cuneiform (medial/plantar surface) and base of 1st metatarsal (the tendon passes deep to the extensor retinacula)

Question 3

Tibialis anterior action

Answer 3

Dorsiflexes and inverts the foot; assists in holding up the medial longitudinal arch of the foot

Question 4

Tibialis anterior innervation and spinal level

Answer 4

Deep fibular L4-5

Question 5

Extensor Digitorum longus origin

Answer 5

Lateral tibial condole, proximal anterior surface of fibula, interosseous membrane, and deep fascia

Question 6

Extensor digitorum longus action

Answer 6

Extend toes 2-5 at MTP & IP joints ; assist dorsiflexion and Eversion of foot

Question 7

Extensor digitorum longus innervation and spinal level

Answer 7

Deep fibular L5-S1

Question 8

Fibularis Tertius origin

Answer 8

Distal anterior surface of fibula

Question 9

Fibularis tertius insertion

Answer 9

Dorsal surface of base of 5th metatarsal

Question 10

Fibularis tertius action

Answer 10

Everts & dorsiflexes the foot

Question 11

Fibularis tertius innervation and spinal level

Answer 11

Deep fibular L5-S1

Question 12

Extensor hallucis longus origin

Answer 12

Middle 1/3 of the anterior surface of the fibula & interosseous membrane

Question 13

Extensor hallucis longus insertion

Answer 13

Base of distal phalanx of the great toe

Question 14

Extensor hallicus longus action

Answer 14

Dorsiflexes (extends) the great toe at MTP and IP joints; assists dorsiflexion and inversion of foot from neutral (can evert from inverted position)

Question 15

Extensor hallicus longus innervation and spinal level

Answer 15

Deep fibular L5

Question 16

Fibularis longus origin

Answer 16

Superior 1/2 of the lateral surface of the fibula and adjacent fascia

Question 17

Fibularis longus insertion

Answer 17

Plantar surface of the 1st (medial) cuneiform and 1st metatarsal

Question 18

Fibularis longus action

Answer 18

Eversion of the foot; assists plantarflexion and helps maintain the twisted configuration of the “forefoot”; support transverse arch

Question 19

Fibularis longus innervation and spinal level

Answer 19

Superficial fibular L5-S1

Question 20

Fibularis Brevis origin

Answer 20

Lower 1/2 of the lateral surface of the fibula and adjacent fascia

Question 21

Fibularis brevis insertion

Answer 21

Lateral side of the base of the 5th metatarsal (“fibular tubercle”)

Question 22

Fibularis brevis action

Answer 22

Eversion of the foot; assist plantarflexion

Question 23

Fibularis brevis innervation and spinal level

Answer 23

Superficial fibular L5-S1

Question 24

Gastrocnemius origin

Answer 24

Medial head: medial femoral condyle

Lateral head: lateral femoral condyle

Question 25

Gastrocnemius insertion

Answer 25

Calcaneal tuberosity (posterior surface of calcaneous)

Question 26

Gastrocnemius action

Answer 26

Plantarflexion Foot Flexes at knee in open chain Extends at knee in closed chain

Question 27

Gastrocnemius innervation and spinal level

Answer 27

Tibial S1-2

Question 28

Soleus origin

Answer 28

Soleal line and middle 1/3 of medial border of tibia and upper 1/3 of posterior surface of fibula

Question 29

Soleus insertion

Answer 29

Calcaneal tuberosity

Question 30

Soleus action

Answer 30

Plantarflex foot; by preventing dorsiflexion at ankle it helps prevent flexion at the knee( could extend knee in closed chain)

Question 31

Soleus innervation and spinal level

Answer 31

Tibial S1-2

Question 32

Popliteus origin

Answer 32

Lateral epicondyle and condyle of femur (via joint capsule of the knee), posterior horn of the lateral meniscus

Question 33

Popliteus insertion

Answer 33

Upper/posterior tibia above the soleal line

Question 34

Popliteus action

Answer 34

Internal rotation of tibia; assist knee flexion

Question 35

Popliteus innervation and spinal level

Answer 35

Tibial L4-S1

Question 36

Plantaris origin

Answer 36

Lateral epicondyle of the femur (posterior surface)

Question 37

Plantaris insertion

Answer 37

Calcaneal tuberosity

Question 38

Plantaris action

Answer 38

Plantarfkex foot, more used in proprioception

Question 39

Plantaris innervation and spinal level

Answer 39

Tibial S1-2

Question 40

Flexor hallicus longus origin

Answer 40

Lower 2/3 of posterior surface of fibula ; and interosseous membrane

Question 41

Flexor hallicus longus insertion

Answer 41

Base of distal phalanx of the great toe

Question 42

Flexor hallicus longus action

Answer 42

Flex great toe at MTP and IP; assist plantarflexion of foot; support medial longitudinal arch; inversion

Question 43

Flexor hallicus longus innervation and spinal level

Answer 43

Tibial L5-S2

Question 44

Flexor digitorum longus origin

Answer 44

Middle 1/3 of the posterior surface of the tibia

Question 45

Flexor digitorum longus insertion

Answer 45

Plantar surface of the base of distal phalanges 2-5

Question 46

Flexor digitorum longus action

Answer 46

Flex toes 2-5 at MTP and IP joints; assist foot plantarflexion; inversion

Question 47

Flexor digitorum longus innervation and spinal level

Answer 47

Tibial L5-S2

Question 48

Tibialis posterior origin

Answer 48

Upper aspect of the posterolateral surface of tibia, fibula, and interosseous membrane

Question 49

Tibialis posterior insertion

Answer 49

navicular tuberosity ( & maybe spring ligament); cuneiform; sends slips of tendon to plantar surfaces of other tarsals and bases of metatarsals 2-4

Question 50

Tibialis posterior action

Answer 50

Inverts and adduct (medially rotates) the foot; assist plantarflexion; support longitudinal and transverse arches

Question 51

Tibialis posterior innervation and spinal level

Answer 51

Tibial L4-5