Extensor Hallucis Longus
The structure indicated is the extensor hallucis longus muscle.
The extensor hallucis longus is one of the four muscles of the anterior compartment of the leg. The muscles of the leg consist of three compartments:
In the anterior compartment are the four following muscles:
- Tibialis anterior
- Extensor hallucis longus
- Extensor digitorum longus
- Fibularis tertius
The muscles of the anterior compartment of the leg serve to dorsiflex the ankle joint, extend the toes and invert the foot, and they are supplied by the deep fibular (peroneal) nerve.
Origin: Middle half of medial fibula and interosseous membrane
Insertion: Dorsal base of distal phalanx of great toe
Innervation: Deep fibular nerve
Action: Extension of great toe. Dorsiflexion of foot.
Learn more about the anatomy of the leg muscles in this tutorial!