Lecture 19: Posterior Compartment (lower leg)

Question 1

gastrocnemius

Answer 1

• P: medial and lateral condyles of femur
• D: heel via calcaneal tendon
• Action: flex at knee and ankle
• I: tibial n (S1,S2)

Question 2

soleus

Answer 2

• P: fibula, tibia, interosseous membrane
• D: calcaneus via Achilles tendon
• Action: plantar flex @ ankle
• I: tibial n (S1,S2)

Question 3

popliteus

Answer 3

• P: lateral condyle of femur and lateral meniscus
• D: post surface of tibia
• Action: externally rotate femur, internally rotate tibia, counterrotation of femur and tibia to unlock knee (kind of destabilize knee)
• I: tibial n. (L4-S1)

Question 4

tibialis posterior (“Tom”)

Answer 4

• P: tib/fib/interosseous mem
• D: calcaneus, cuboid, cuneiforms, base of metatarsals 2-4
• A: plantarflex @ ankle, inversion of intertarsal joint, synergize w/ fib. longus to maintain transverse arch
• I: tibial n. (L4, L5)

Question 5

flexor hallucis longus (“Harry”)

Answer 5

-P: fibula, interosseous membrane, little tibia
-D: distal phalanx of digit 1
-Action: plantarflex @ ankle & flex digit 1 (toe off when you walk), inversion of intertarsal
I: tibial N. (S2, S3)

Question 6

flexor digitorum longus (“Dick”)

Answer 6

• P: tib/fib/interosseous mem
• D: distal phalanx of digits 2-5
• A: plantarflex @ ankle, flex digits 2-5, inversion of intertarsal joint
• I: Tibial n. (S2, S3)