Muscles of the Anterior Leg

Question 1

Muscles

Answer 1

Tibialis anterior
Extensor digitorum longus
Extensor hallucis longus
Fibularis tertius

Question 2

Innervation

Answer 2

Deep fibular nerve

Question 3

Blood supply

Answer 3

Anterior tibial artery

Question 4

Tibialis anterior

Answer 4

• Origin - lateral surface of tibia
• Attachment - medial cuneiform and base of metatarsal I
• Actions - dorsiflexion and inversion of the foot
• Innervation - deep fibular nerve

Question 5

Extensor digitorum longus

Answer 5

• Origin - lateral condyle of the tibia and medial surface of fibula
• Insertion - splits into 4 tendons and each inserts onto a toe
• Actions - extension of lateral 4 toes, dorsiflexion of foot
• Innervation - deep fibular nerve

Question 6

Extensor hallucis longus

Answer 6

• Origin - medial surface of fibular sheath
• Attachment - base of distal phalanx of big toe
• Actions - extension of big toe, dorsiflexion of foot
• Innervation - deep fibular nerve

Question 7

Fibularis tertius

Answer 7

• Origin - medial surface of fibula
• Attachment - metatarsal V
• Actions - eversion and dorsiflexion of the foot
• Innervation - deep fibular nerve

Question 8

Footdrop

Answer 8

Paralysis of the muscles in anterior compartment of the leg
Common fibular nerve damage (where the deep fibular nerve arises)
Unopposed pull of plantarflexor muscles -> permanent plantarflexion
Patient flicks foot outwards while walking known as eversion flick (slap gait)