Anterior and lateral leg muscles

Question 1

Tibialis anterior
* origin
* insertion
* action
* innervation

Answer 1

• origin: lateral condyle of tibia; lateral aspect of tibia; interosseous membrane of the leg
• insertion: base of first metatarsal; medial cuneiform bone
• action: dorsiflexion of the foot; inversion of the foot
• innervation: deep peroneal nerve

Question 2

Extensor digitorum longus
* origin
* insertion
* action
* innervation

Answer 2

• origin: lateral condyle of the tibia; upper fibula; interosseous membrane of leg
• insertion: middle and distal phalanges of lateral four digits
• action: dorsiflexion of the foot; extension of digits 2-5
• innervation: deep peroneal nerve

Question 3

Extensor hallucis longus
* origin
* insertion
* action
* innervation

Answer 3

• origin: medial aspect of fibula; interosseous membrane of leg
• insertion: dorsal surface of first distal phalanx
• action: extension of digit 1; dorsiflexion of the foot; inversion of foot
• innervation: deep peroneal nerve

Question 4

Peroneus/fibularis longus
* origin
* insertion
* action
* innervation

Answer 4

• origin: head of fibula; upper fibula
• insertion: base of first metatarsal, medial cuneiform
• action: eversion of foot; (weak) plantarflexion of foot
• innervation: superficial peroneal nerve

Question 5

Peroneus/fibularis brevis
* origin
* insertion
* action
* innervation

Answer 5

• origin: lateral distal fibula
• insertion: lateral side of fifth metatarsal
• action: eversion of foot; (weak) plantarflexion of the foot
• innervation: superficial peroneal nerve