Leg

Question 0

What are the four muscles of the anterior compartment?

Answer 0

Tibialis anterior, extensor digitorum longus, extensor hallucis longus, and fibularis tertius

Question 1

What are the three compartments of the leg?

Answer 1

Anterior, lateral, and posterior compartments

Question 2

What are the two muscles of the lateral compartment?

Answer 2

Fibularis longus and fibularis brevis

Question 3

What does the deep fibular nerve pierce as it goes deep?

Answer 3

Intermuscular septum

Question 4

What does the anterior tibial artery pierce as it goes deep?

Answer 4

Interosseous membrane

Question 5

What divides the superificial and deep compartments of the posterior leg?

Answer 5

Transverse intermuscular septum

Question 6

What are the superficial muscles of the posterior compartment of the leg?

Answer 6

Gastrocnemius, soleus, and plantaris

Question 7

Triceps surae

Answer 7

Tendons of the gastrocnemius and soleus come together to form the calcaneal tendon

Question 8

What is the most superficial muscle in the posterior compartment of the leg?

Answer 8

Gastrocnemius

Question 10

What are the four muscles of the deep compartment of the posterior leg?

Answer 10

Popliteus, flexor digitorum longus, flexor hallucis longus, and tibialis posterior

Question 11

What is the only muscle of the deep compartment of the posterior thigh to act on the knee joint?

Answer 11

Popliteus

Question 12

How do the popliteal artery and tibial nerve exit the popliteal fossa?

Answer 12

Tendinous arch of soleus

Question 13

Tibialis anterior

Answer 13

Origin: lateral condyle and superior half of the lateral surface of the tibia and interosseous membrance

Insertion: medial and inferior surfaces of medial cuneiform and base of 1st metatarsal

Innervation: deep fibular nerve (L4,L5)

Action: dorsiflexes ankle, inverts ankle, and supports medial longitudinal arch of foot

Question 14

Extensor hallucis longus

Answer 14

Origin: middle part of the anterior surface of the fibula and the interosseous membrane

Insertion: dorsal aspect of base of the distal phalanx of the great toe

Innervation: deep fibular nerve (L5,S1)

Action: extend great toe and dorsiflex ankle

Question 15

Extensor digitorum longus

Answer 15

Origin: lateral condyle of tibia and superior three fourths of the anterior surface of the interosseous membrane

Insertion: middle and distal phalanges of the lateral four digits

Innervation: deep fibular nerve (L5,S1)

Action: extend lateral four digits and dorsiflex ankle

Question 16

Fibularis tertius

Answer 16

Origin: inferior third of the anterior surface of the fibula and interosseous membrane

Insertion: dorsum of base of 5th metatarsal

Innervation: deep fibular nerve (L5,S1)

Action: dorsiflex the ankle and aid in eversion of foot

Question 17

Fibularis longus

Answer 17

Origin: superior two thirds of the lateral surface of the fibula

Insertion: medial cuneiform and base of the the 1st metatarsal

Innervation: superficial fibular nerve (L5,S1,S2)

Action: everts foot, weakly plantarflexes ankle, and supports transverse arch of foot

Question 18

Fibularis brevis

Answer 18

Origin: inferior two thirds of the lateral surface of the fibula

Insertion: dorsal surface of tuberosity of base of 5th metatarsal

Innervation: superficial fibular nerve (L5,S1,S2)

Action: none

Question 19

Gastrocnemius

Answer 19

Origin: (lateral head) lateral aspect of lateral condyle of femur (medial head) popliteal surface of femur superior to medial condyle

Insertion: posterior surface of calcaneous via calcaneal tendon

Innervation: tibial nerve (S1,S2)

Action: plantarflexes ankle when knee is extended, raises heel during walking, and flexes leg at knee joint

Question 20

Soleus

Answer 20

Origin: posterior aspect of head of fibula, superior quarter of posterior surface of fibula, soleal line, and medial border of tibia

Insertion: posterior surface of calcaneous via calcaneal tendon

Innervation: tibial nerve (S1,S2)

Action: plantarflexes ankle

Question 21

Plantaris

Answer 21

Origin: inferior end of lateral supracondylar line of femur and oblique popliteal ligament

Insertion: posterior surface of calcaneous via calcaneal tendon

Innervation: tibial nerve (S1,S2)

Action: assists gastrocnemius with plantarflexion of ankle

Question 22

Popliteus

Answer 22

Origin: lateral surface of lateral condyle of femur and lateral meniscus

Insertion: posterior surface of tibia superior to soleal line

Innervation: tibial nerve (L4,L5,S1)

Action: weakly flexes knee and unlocks knee joint by laterally rotating femur on fixed tibia

Question 23

Flexor hallucis longus

Answer 23

Origin: inferior 2/3 of posterior surface of fibula and inferior part of interosseous membrane

Insertion: base of distal phalanx of great toe

Innervation: tibial nerve (S2,S3)

Action: flexes great toe, weakly plantarflexes ankle, and supports medial longitudinal arch of foot

Question 24

Flexor digitorum longus

Answer 24

Origin: medial part of posterior surface of tibia inferior to soleal line and by a broad tendon to the fibula

Insertion: bases of distal phalanges of lateral four digits

Innervation: tibial nerve (S2,S3)

Action: flexes lateral four digits, plantarflexes ankle, and supports longitudinal arch of foot

Question 25

Tibialis posterior

Answer 25

Origin: interosseous membrane, posterior surface of tibia inferior to soleal line, and posterior surface of fibula

Insertion: tuberosity of navicular, cuneiforms, cuboid, and bases of 2-4th metatarsals

Innervation: tibial nerve (L4,L5)

Action: plantarflexes ankle, inverts foot, and supports medial longitudinal arch of foot

Question 26

What are the muscles of the tarsal tunnel?

Answer 26

Tibialis posterior, flexor digitorum longus, and flexor hallucis longus