Gross 2 Lower Leg **Muscles, Nerves, Actions

Question 1

What are the attachments of the Tibialis Anterior?

Answer 1

Proximal: Lateral condyle and superior half of lateral surface of tibia and interosseous membrane
(under extensor retinaculum)

Distal: Medial and inferior surface of medial cuneiform and base of 1st metatarsal

Question 2

What nerve innervates the Tibialis Anterior? and roots?

Answer 2

Deep Fibular Nerve (L4,L5 and S1)

Question 3

What are the actions of Tibialis Anterior?

Answer 3

Dorsiflexes ankle and inverts foot

Question 4

What are the attachments of the Extensor Digitorum Longus?

Answer 4

Proximal: Lateral condyle of tibia and superior three quarters of medial surface of fibula and interosseous membrane
(Under extensor retinaculum)

Distal: Middle and distal phalanges of lateral four digits

Question 5

What nerve innervates Extensor Digitorum Longus? and roots?

Answer 5

Deep Fibular Nerve (L4, L5, and S1)

Question 6

What is the action of Extensor Digitorum Longus?

Answer 6

Extends lateral four digits and dorsiflexes ankle

Question 7

What are the attachments of Extensor Hallucis longus?

Answer 7

Proximal: Middle part of anterior surface of fibula and interosseous membrane

Distal: Dorsal aspect of base of distal phalanx of great toe (hallux)

Question 8

What nerve innervates Extensor Hallucis Longus? and root?

Answer 8

Deep Fibular Nerve (L4, L5, S1)

Question 9

What are the actions of Extensor Hallucis Longus?

Answer 9

Extends great toe (hallux) and dorsiflexes ankle

Question 10

What are the attachments of Fibularis Tertius?

Answer 10

Proximal: Inferior third of anterior surface of fibula and interosseous membrane

Distal: Dorsum of base of 5th metatarsal

Question 11

What nerve innervates Fibularis Tertius?

Answer 11

Deep Fibular Nerve (L4, L5, and S1)

Question 12

What is the action of Fibularis Tertius?

Answer 12

Dorsiflexes ankle and aids in eversion of foot

Question 13

What are the attachments of Fibularis Longus?

Answer 13

Proximal: Head and Superior two-thirds of lateral surface of fibula

Distal: Base of 1st metatarsal and medial cuneiform

Question 14

What nerve innervates Fibularis Longus?

Answer 14

Superficial Fibular Nerve (L5, S1, S2)

Question 15

What is the action of Fibularis Longus?

Answer 15

Everts foot and weakly planterflexes ankle

Question 16

What are the attachments for Fibularis Brevis?

Answer 16

Proximal: Inferior two-thirds of lateral surface of fibula

Distal: Dorsal surface of tuberosity on lateral side of base of 5th metatarsal

Question 17

What nerve innervates Fibularis Brevis?

Answer 17

Superficial Fibular Nerve
(L5, S1, S2)

Question 18

What are the actions of Fibularis Brevis?

Answer 18

Everts foot and weakly platarflexes ankle

Question 19

What are the attachments for Gastrocnemius? (Lateral Head)

Answer 19

Proximal: Lateral Aspect of lateral condyle of femur

Distal: Posterior surface of calcaneus via calcaneal tendon

Question 20

What are the attachments for Gastrocnemius? (Medial Head)

Answer 20

Proximal: Popliteal surface of femur; superior to medial condyle

Distal: (same as lateral head)
Posterior surface of calcaneus via calcaneal tendon

Question 21

What nerve innervates the Gastrocnemius?

Answer 21

Tibial Nerve (L4-S3)

Question 22

What are the actions of Gastrocnemius?

Answer 22

Planterflexes ankle when knee is extended; raises heel during walking; flexes leg at knee joint

Question 23

What are the attachments for Soleus?

Answer 23

Proximal: Posterior aspect of head and superior quarter of posterior surface of fibula; Soleal line and middle third of medial border of tibia; Tendinous arch extending between the boney attachments

Distal: Posterior surface of calcaneus via calcaneal tendon

Question 24

What nerve innervates soleus?

Answer 24

Tibial Nerve (L4-S3)

Question 25

What are the actions of Soleus?

Answer 25

Planterflexes ankle independent of position of knee; steadies leg on foot

Question 26

What are the attachments for Plantaris?

Answer 26

Proximal: Inferior end of lateral supracondylar line of femur; oblique popliteal ligament Distal: Posterior surface of calcaneus via calcaneal tendon

Question 27

What nerve innervates Plantaris?

Answer 27

Tibial Nerve (L4-S3)

Question 28

What are the actions for Plantaris?

Answer 28

Weakly assist gastrocnemius in planterflexing ankle

Question 29

What are the attachments of Popliteus?

Answer 29

Proximal: Lateral surface of lateral condyle of femur and lateral meniscus Distal: Posterior surface of tibia and superior to soleal line

Question 30

What nerve innervates Popliteus?

Answer 30

Tibial Nerve (L4-S3)

Question 31

What are the actions of Popliteus?

Answer 31

Weakly flexes knee and Unlocks it by rotating femur 5° on fixed tibia; medially rotates tibia of unplanted limb

Question 32

What are the attachments for Flexor Hallucis Longus?

Answer 32

Proximal: Inferior two thirds of posterior surface of fibula; inferior part of interosseous membrane Distal: Base of distal phalanx of great toe (Hallux)

Question 33

What nerve innervates Flexor Hallucis Longus?

Answer 33

Tibial Nerve (L4-S3)

Question 34

What are the actions of Flexor Hallucis Longus?

Answer 34

Flexes great toe at all joint; weakly planterflexes ankle; supports medial longitudinal arch of foot

Question 35

What are the attachments of Flexor Digitorum Longus?

Answer 35

Proximal: Medial part of posterior surface of tibia inferior to soleal line; by a broad tendon to fibula Distal: Bases of distal phalanges of lateral four digits

Question 36

What nerve innervates Flexor Digitorum Longus?

Answer 36

Tibial Nerve (L4-S3)

Question 37

What are the actions for Flexor Digitorum Longus?

Answer 37

Flexes lateral four digits; planterflexes ankle; supports longitudinal arches of foot

Question 38

What are the attachments for Tibialis Posterior?

Answer 38

Proximal: Interosseous membrane; posterior surface of tibia inferior to soleal line; posterior surface of fibula Distal: Tuberosity of navicular(*only one we need*), cuneiform, cuboid, and sustentaculum tali of calcaneus; bases of 2nd, 3rd, and 4th metatarsals

Question 39

What nerve innervates Tibialis Posterior?

Answer 39

Tibial Nerve (L4-S3)

Question 40

What is the actions for Tibialis Posterior?

Answer 40

Planterflexes ankle; inverts foot