Anatomy Of The Extensor Hallucis Longus Muscle

Courtesy: Prof Nabil Ebraheim, University of Toledo, Ohio, USA

 

Anatomy of Extensor Hallucis Longus

• The extensor hallucis longs muscle lies in the anterior extensor compartment of the leg.
• There are four muscle compartments within the leg (Q: “How many muscle compartments are present in the leg”)

1. Anterior Compartment
2. Lateral Compartment
3. Superficial posterior compartment
4. Deep posterior compartment

Anterior compartment

There are four muscles located within the anterior compartment of the leg supplied by Deep Peroneal Nerve (Q: “Which are the muscles supplied by the deep peroneal nerve”)

o Tibialis Anterior
o Extensor Hallucis longus
o Extensor Digitorum Longus
o Peroneus Teritius

Extensor Hallucis Longus
Origin -Arises from the middle 2/4 of the anterior surface of the fibula.
Insertion -The extensor hallucis longus inserts in the distal phalanx of the big toe.

The muscle makes a tendon above the superior extensor retinaculum and this tendon passes under the superior extensor retinaculum and
the inferior extensor retinaculum .It inserts into the distal phalanx of the big toe.

FUNCTION
Dorsiflexion of the ankle and extension of the big toe toe.

Relationship of the Anterior Tibial Artery to the Extensor Hallucis Longus Muscle (Q:” What is the relation between the Anterior Tibial Artery and the Extensor Hallucis Longus)
o Initially, the artery runs proximally between the tibialis anterior medially and the extensor digitorum Longus laterally.
o As the extensor hallucis longus muscle takes origin from the middle 2/4 of the anterior fibula, then the anterior tibial artery lies between the the tibialis anterior muscle and the extensor hallucis longus muscle.
o The extensor hallucis longus muscle then crosses the leg medially to take a position in the medial side, to go to the big toe.
o The anterior tibial artery will be between the Extensor Hallucis Longus and the Extensor Digitorum Longus tendons in the distal part of the leg and in front of the ankle.

Dorsalis pedis, which is a continuation of the anterior tibial artery is in the first web space. It is between the extensor hallucis longs medially and the extensor digitorum longs laterally. (Q: “Where is the dorsalis pedis artery located”)