Posterior compartment of the leg

Question 1

What is the proximal attachment of the gastrocnemius?

Answer 1

Lateral head: lateral condyle of femur

Medial head: popliteal surface of femur

Question 2

What is the distal attachment of the gastrocnemius, soleus, and plantaris?

Answer 2

Posterior surface of calcaneus via calcaneal tendon

Question 3

What nerve innervates the gastrocnemius, soleus, and plantaris?

Answer 3

Tibial nerve (S1,S2)

Question 4

What is the main action of the gastrocnemius?

Answer 4

• Plantarflexes ankle
• Raises heal when walking
• Flexes leg at knee joint

Question 5

What is the proximal attachment of the soleus?

Answer 5

Head of fibula, soleal line and medial border of tibia, tendinous arch

Question 6

What is the main action of the soleus?

Answer 6

• Plantarflexes ankle independent of position of knee

- Steadies leg on foot

Question 7

What is the proximal attchment of the plantaris?

Answer 7

Supracondylar line of femur and oblique popliteal ligament

Question 8

What is the main action of the plantaris?

Answer 8

Weakly assists gastrocnemius in plantarflexing ankle

Question 9

What is the proximal attachment of the popliteus?

Answer 9

Lateral surface of condyle of femur and lateral meniscus

Question 10

What is the distal attachment of the popliteus?

Answer 10

Tibia superior to soleal line

Question 11

What nerve innervates the popliteus?

Answer 11

Tibial nerve (L4,L5,S1)

Question 12

What is the main action of the popliteus?

Answer 12

• Weakly flexes knee

- Medially rotates tibia of unplanted limb

Question 13

What is the proximal attachment of the flexor hallucis longus?

Answer 13

Posterior surface of fibula; inferior part of interosseous membrane.

Question 14

What is the distal attachment of the flexor hallucis longus?

Answer 14

Distal phalanx of great toe (hallux)

Question 15

What nerve innervates the flexor hallucis longus and flexor digitorum longus?

Answer 15

Tibial nerve (S2,S3)

Question 16

What is the main action of the flexor hallucis longus?

Answer 16

• Flexes great toe
• Weakly plantarflexes ankle
• Supports medial longitudinal arch of foot

Question 17

What is the proximal attachment of the flexor digitorum longus?

Answer 17

Tibia inferior to soleal line, by a broad tendon of fibula

Question 18

What is the distal attachment of the flexor digitorum longus?

Answer 18

Distal phalanges of lateral four digits

Question 19

What is the main action of the flexor digitorum longus?

Answer 19

• Flexes lateral 4 digits
• Plantarflexes ankle
• Supports longitundinal arches of foot

Question 20

What is the proximal attachment of the tibialis posterior?

Answer 20

Interosseous membrane, tibia, posterior surface of fibula

Question 21

What is the distal attachment of the tibialis posterior?

Answer 21

Tuberosity of navicular, cuneiform, cuboid, and sustentaculum tali of calcaneus; bases of 2nd, 3rd, and 4th metatarsals

Question 22

What nerve innervates the tibialis posterior?

Answer 22

Tibial nerve (L4,L5)

Question 23

What is the main action of the tibialis posterior?

Answer 23

• Plantarfelxes ankle

- Inverts foot