Extensor digitorum brevis muscle

Extensor digitorum brevis muscle

The mucous sheaths of the tendons around the ankle. Lateral aspect. (Extensor dig. brevis labeled at upper right.)
Details
Origin Dorsal surface of calcaneus
Insertion Proximal dorsal region of middle phalanges 2, 3 and 4
Artery Dorsalis pedis artery
Nerve Deep fibular nerve
Actions Extends digits 2 through 4
Antagonist Flexor digitorum longus, Flexor digitorum brevis
Identifiers
Latin Musculus extensor digitorum brevis
TA A04.7.02.055
FMA 51140

Anatomical terms of muscle

The extensor digitorum brevis muscle (sometimes EDB) is a muscle on the upper surface of the foot that helps extend digits 2 through 4.

Structure

Origin: forepart of upper and lateral surface of calcaneus, in front of groove for peroneus brevis, from interosseous talocalcaneal ligament, stem of inferior extensor retinaculum.

Course

Course: fibres pass obliquely forwards and medially cross dorsum of foot and end in four tendons. The medial part of muscle ends in tendon which crosses the dorsalis pedis artery, inserts into dorsal surface base of PPX of great toe and is termed extensor hallucis brevis. The other three tendons insert into lateral sides of tendon of extensor digitorum longus which insert into the 2nd, 3rd and 4th toes.

Innervation

Nerve supply: lateral terminal branch of Deep Peroneal Nerve (deep fibular nerve) (proximal sciatic branches L4-L5, but most clinically relevant L5 with L4/L5 spinal disc herniation causing L5 lesion). Same innervation of Extensor Hallucis Brevis

Action

Action: extends MTP of 1st to 4th digits and assists in extending the IP joints of 2nd, 3rd, and 4th digits.

Note: without EDL there is no extension of 5th digit.

Additional images

See also

External links


This article is issued from Wikipedia - version of the 10/15/2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.