Extensor hallucis longus muscle

The extensor hallucis longus muscle is a thin skeletal muscle, situated between the tibialis anterior and the extensor digitorum longus. It extends the big toe and dorsiflects the foot. It also assists with foot eversion and inversion.

Extensor hallucis longus muscle
The mucous sheaths of the tendons around the ankle. Lateral aspect. (Ext. hall. long. labeled at upper left.)
Animation
Details
OriginArises from the middle portion of the fibula on the anterior surface and the interosseous membrane
InsertionInserts on the dorsal side of the base of the distal phalanx of the big toe
ArteryAnterior tibial artery
NerveDeep fibular nerve, L5 (L4-S1)
ActionsExtends (raises) the big toe and assists in dorsiflexion of the foot at the ankle. Also is a weak evertor/invertor
AntagonistFlexor hallucis longus, flexor hallucis brevis
Identifiers
Latinmusculus extensor hallucis longus
TA98A04.7.02.040
TA22650
FMA22533
Anatomical terms of muscle

Structure

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The muscle ends as a tendon of insertion. The tendon passes through a distinct compartment in the inferior extensor retinaculum of foot. It crosses anterior tibial vessels lateromedially near the bend of the ankle.[citation needed] In the foot, its tendon is situated at along the medial side of the dorsum of the foot.[1] Opposite the metatarsophalangeal articulation, the tendon gives off a thin prolongation on either side, to cover the surface of the joint. An expansion from the medial side of the tendon is usually inserted into the base of the proximal phalanx.[citation needed]

Origin

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The extensor hallucis longus muscle arises from the middle portion of[2] the anterior surface[citation needed] of the fibula and adjacent interosseous membrane of the leg.[3] Its origin is medial to the origin of the extensor digitorum longus muscle.[citation needed]

Insertion

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The muscle inserts at the base of the distal phalanx of the great toe.[4]

Nerve supply

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The muscle receives motor innervation from the deep fibular nerve (L5)[3] (a branch of common fibular nerve).

Relations

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The anterior tibial vessels and deep fibular nerve pass between this muscle and the tibialis anterior muscle.

Variation

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Occasionally united at its origin with the extensor digitorum longus.

The extensor ossis metatarsi hallucis, a small muscle, sometimes found as a slip from the extensor hallucis longus, or from the tibialis anterior, or from the extensor digitorum longus, or as a distinct muscle; it traverses the same compartment of the transverse ligament with the extensor hallucis longus.

Actions/movements

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The muscle extends/dorsiflects the big toe (primary action), and dorsiflects the foot (secondary action).[3]

Additional Images

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References

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  This article incorporates text in the public domain from page 481 of the 20th edition of Gray's Anatomy (1918)

  1. ^ Sinnatamby, Chummy (2011). Last's Anatomy (12th ed.). p. 144. ISBN 978-0-7295-3752-0.
  2. ^ Sinnatamby, Chummy (2011). Last's Anatomy (12th ed.). p. 144. ISBN 978-0-7295-3752-0.
  3. ^ a b c Sinnatamby, Chummy (2011). Last's Anatomy (12th ed.). p. 144. ISBN 978-0-7295-3752-0.
  4. ^ Sinnatamby, Chummy (2011). Last's Anatomy (12th ed.). p. 144. ISBN 978-0-7295-3752-0.
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