Unit 5 - Lower Limb: Muscles of A Compartment of Leg (Ex. IV)

Question 1

extensor hallucis longus

Answer 1

O: middle 1/3 of M surface of fibula; interosseous membrane
I: dorsal aponeurosis @ and base of distal phalanx of 1st toe
Inn: deep fibular n. (L4, L5)
A: dorsiflexion @ talocrural joint; subtalar joint - active in eversion and inversion (pronation/supination), depending on initial position of foot; extends MTP and IP joints of big toe

Question 2

extensor digitorum longus

Answer 2

O: head and M surface of fibula; L condyle of tibia; interosseous membrane
I: @ dorsal aponeuroses at bases of distal phalanges of toes 2-5
Inn: deep fibular n. (L4, L5)
A: dorsiflexion @ talocrural joint; eversion (pronation) @ subtalar joint; extends MTP and IP joints of toes 2-5

Question 3

fibularis tertius

Answer 3

O: A border of distal fibula
I: base of 5th metatarsal
Inn: deep fibular n. (L4, L5)
A: dorsiflexion @ talocrural joint; eversion (pronation) @ subtalar joint

Question 4

tibialis A

Answer 4

O: upper 2/3 of L surface of tibia; interosseous membrane; highest part of superficial crural fascia
I: M and plantar surfaces of M cuneiform; M base of 1st metatarsal
Inn: deep fibular n. (L4, L5)
A: dorsiflexion @ talocrural joint; inversion (supination) @ subtalar joint