Muscles Of The Posterior Compartment Of The Leg

Question 0

Insertion of the gastrocnemius

Answer 0

Posterior surface of calcaneus via calcaneal tendon

Question 1

Origin of the gastrocnemius

Answer 1

Lateral head: lateral aspect of lateral condyle of femur

Medial head: popliteal surface of femur, superior to medial condyle

Question 2

Innervation of the gastrocnemius

Answer 2

Tibial nerve (S1, S2)

Question 3

Actions of the gastrocnemius

Answer 3

Plantarflexes ankle when knee is extended

Raises heel during walking and flexes leg at knee joint

Question 4

Origin of the soleus (SOL)

Answer 4

Posterior aspect of head of fibula
Superior quarter of posterior surface of fibula
Soleal line
Medial border of tibia

Question 5

Insertion of soleus (SOL)

Answer 5

Posterior surface of calcaneus via calcaneal tendon

Question 6

Innervation of the soleus (SOL)

Answer 6

Tibial nerve (S1, S2)

Question 7

Actions of the soleus (SOL)

Answer 7

Plantarflexes ankle

Steadies leg on foot

Question 8

Origin of the plantaris

Answer 8

Inferior end of lateral supracondylar line of femur and oblique popliteal ligament

Question 9

Insertion of the plantaris

Answer 9

Posterior surface of calcaneus via calcaneal tendon

Question 10

Innervation of the plantaris

Answer 10

Tibial nerve (S1, S2)

Question 11

Actions of the plantaris

Answer 11

Weakly assists gastrocnemius in plantarflexing ankle

Question 12

Origin of the popliteus

Answer 12

Lateral surface of lateral condyle of femur and lateral meniscus

Question 13

Insertion of the popliteus

Answer 13

Posterior surface of tibia superior to soleal line

Question 14

Innervation of popliteus

Answer 14

Tibial nerve (L4, L5, S1)

Question 15

Actions of the popliteus

Answer 15

Weakly flexes knee and unlocks it by laterally rotating femur on fixed tibia, or medially rotating tibia of unplanted limb

Question 16

Origin of the flexor hallucis longus (FHL)

Answer 16

Inferior two thirds of posterior surface of fibula and inferior part of interosseous membrane

Question 17

Insertion of the flexor hallucis longus (FHL)

Answer 17

Base of distal phalanx of great toe (hallux)

Question 18

Innervation of the flexor hallucis longus (FHL)

Answer 18

Tibial nerve (S2, S3)

Question 19

Action of the flexor hallucis longus (FHL)

Answer 19

Flexes great toe at all joints
Weakly Plantarflexes ankle
Supports medial longitudinal arch of foot

Question 20

Origin of the flexor digitorum longus (FDL)

Answer 20

Medial part of posterior surface of tibia inferior to soleal line and by a broad tendon to fibula

Question 21

Insertion of the flexor digitorum longus (FDL)

Answer 21

Bases of the distal phalanges of lateral four digits

Question 22

Innervation of the flexor digitorum longus (FDL)

Answer 22

Tibial nerve (S2, S3)

Question 23

Actions of the flexor digitorum longus (FDL)

Answer 23

Flexes lateral four digits
Plantarflexes ankle
Supports longitudinal arches of foot

Question 24

Origin of the tibialis posterior

Answer 24

Interosseous membrane
Posterior surface of tibia inferior to soleal line
Posterior surface of fibula

Question 25

Insertion of tibialis posterior

Answer 25

Primarily to tuberosity of navicular

Also to cuneiforms, cuboid, and bases of 2nd-4th metatarsals

Question 26

Innervation of the tibialis posterior

Answer 26

Tibial nerve (L4, L5)

Question 27

Actions of the tibialis posterior

Answer 27

Plantarflexes ankle
Inverts foot
Supports medial longitudinal arch of foot