The extensor digitorum brevis muscle (sometimes EDB) is a

muscle Skeletal muscles (commonly referred to as muscles) are organs of the vertebrate muscular system and typically are attached by tendons to bones of a skeleton. The muscle cells of skeletal muscles are much longer than in the other types of mus ...

on the upper surface of the foot that helps extend digits 2 through 4.

Structure

The muscle originates from the forepart of the upper and lateral surface of the

calcaneus In humans and many other primates, the calcaneus (; from the Latin ''calcaneus'' or ''calcaneum'', meaning heel) or heel bone is a bone of the tarsus of the foot which constitutes the heel. In some other animals, it is the point of the hock. ...

(in front of the groove for the

peroneus brevis In human anatomy, the fibularis brevis (or peroneus brevis) is a muscle that lies underneath the fibularis longus within the lateral compartment of the leg. It acts to tilt the sole of the foot away from the midline of the body (eversion) and to ...

tendon), from the interosseous talocalcaneal ligament and the stem of the inferior extensor retinaculum. The fibres pass obliquely forwards and medially across the dorsum of the foot and end in four tendons. The medial part of the muscle, also known as

extensor hallucis brevis The extensor hallucis brevis is a muscle on the top of the foot that helps to extend the big toe. Structure The extensor hallucis brevis is essentially the medial part of the extensor digitorum brevis muscle. Some anatomists have debated whethe ...

, ends in a tendon which crosses the dorsalis pedis artery and inserts into the dorsal surface of the base of the proximal phalanx of the great toe. The other three tendons insert into the lateral sides of the tendons of

extensor digitorum longus The extensor digitorum longus is a pennate muscle, situated at the lateral part of the front of the leg. Origin and insertion It arises from the lateral condyle of the tibia; from the upper three-quarters of the anterior surface of the body of ...

for the second, third and fourth toes.

Nerve supply

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 Spinal disc herniation is an injury to the cushioning and connective tissue between vertebrae, usually caused by excessive strain or trauma to the spine. It may result in back pain, pain or sensation in different parts of the body, and physical ...

causing L5 lesion). Same innervation of

Extensor Hallucis Brevis The extensor hallucis brevis is a muscle on the top of the foot that helps to extend the big toe. Structure The extensor hallucis brevis is essentially the medial part of the extensor digitorum brevis muscle. Some anatomists have debated whethe ...

Function

Extensor digitorum brevis extends the first four digits at the

metatarsophalangeal joint The metatarsophalangeal joints (MTP joints), also informally known as toe knuckles, are the joints between the metatarsal bones of the foot and the proximal bones ( proximal phalanges) of the toes. They are condyloid joints, meaning that an elli ...

and assists in extending the second, third and fourth digits at the interphalangeal joint. The fifth digit, lacking any insertion from extensor digitorum brevis, can only be raised by the long extensor.

Additional images

File:Gray268.png, Bones of the right foot. Dorsal surface. File:Gray437.png, Muscles of the front of the leg. File:Gray440_color.png, Cross-section through middle of leg. File:Slide1ABBAA.JPG, Dorsum of Foot. Deep dissection. File:Slide2ABBAA.JPG, Dorsum of Foot. Deep dissection.

External links

* - "The Foot: Muscles" *
PTCentral
{{Authority control Calf muscles Muscles of the lower limb

Structure

Nerve supply

Function

Additional images

See also

External links