Extensor digitorum brevis muscle

From Wikipedia, the free encyclopedia
Jump to: navigation, search
Extensor digitorum brevis muscle
The mucous sheaths of the tendons around the ankle. Lateral aspect. (Extensor dig. brevis labeled at upper right.)
Latin Musculus extensor digitorum brevis
Origin Dorsal surface of calcaneus
Insertion Proximal dorsal region of middle phalanges 2, 3 and 4
Dorsalis pedis artery
Deep fibular nerve
Actions Extends digits 2 through 4
Antagonist Flexor digitorum longus, Flexor digitorum brevis
Gray's p.490
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.


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


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 HNP causing L5 lesion). Same innervation of Extensor Hallucis Brevis


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[edit]

See also[edit]

External links[edit]