Muscles of the Posterior Leg (Superficial and Deep)

Question 1

Gastrocnemius

Answer 1

O: lat head- alt aspect of lat. condyle of femur; med head-popliteal surface of femur, sup. to medial condyle

I:post. surface of calcaneus via. tendocalcaneus

A: plantar flexion, raises heel during walking, flexes knee

N: tibial n. (S1, S2)

Question 2

Soleus

Answer 2

O: post. sup aspect of head of fibula; soleal line; medial border of tibia

I: post. surface of calcaneus via tendocalcaneus

A: plantar flexion, raises heel during walking

N: tibial nerve (S1, S2)

Question 3

Plantaris

Answer 3

O: inf lat. supracondylar line of femur and oblique popliteal ligament

I: fuses with tendocalcaneus

A: weakly helps with plantar flexion and flexion of the knee

N: tibial nerve (S1, S2)

Question 4

Popliteus

Answer 4

O: lat. surface of lat. condyle of femur and lat. meniscus

I: post. surface of tibia; sup. to soleal line

A: weakly flexes knee; unlocks knee (laterally rotates femur on fixed tibia; medially rotates femur on fixed femur)

N: tibial n. (L4, L5, S1)

Question 5

Tibialis Posterior

Answer 5

O: interosseous membrane, post. surface of tibia inf. to soleal line; post. fibula

I: tuberosity of navicular, all three cuneiform bones, bases of 2, 3, 4 metatarsals

A: plantarflexes and inverts foot; supports transverse and med. longitudinal arch

Question 6

Flexor Digitorum Longus

Answer 6

O: med. post surface of tibia inf. to soleal line; aponeurosis to fibula

I: bases of distal phalanges of lat. 4 digits

A: flexes lateral 4 digits; plantar flexes foot; supports medial longitudinal arch of foot

N: tibial n. (S2, S3)

Question 7

Flexor Hallucis Longus

Answer 7

O: inf post. surface of fibula and inf. part of interosseus membrane

I: base of distal phalanx of hallux

A: flexes hallux at all joints and plantar flexes foot; supports longitudinal arch of foot

N: tibial n. (S2, S3)