Extensor pollicis brevis muscle

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Extensor pollicis brevis muscle
Gray1231.png
Front of right upper extremity. (Extensor pollicis brevis labeled at upper left.)
Musculusextensorpollicisbrevis.png
Posterior surface of the forearm. Deep muscles. (Extensor pollicis brevis visible at left.)
Details
Latin musculus extensor pollicis brevis
radius and the interosseous membrane
thumb, proximal phalanx
posterior interosseous artery
posterior interosseous nerve
Actions extension of thumb at metacarpophalangeal joint
Flexor pollicis longus muscle, Flexor pollicis brevis muscle
Identifiers
Gray's p.455
Dorlands
/Elsevier
m_22/12548946
TA A04.6.02.050
FMA FMA:38518
Anatomical terms of muscle

In human anatomy, the extensor pollicis brevis is a skeletal muscle on the dorsal side of the forearm. It lies on the medial side of, and is closely connected with, the abductor pollicis longus.

Structure[edit]

The extensor pollicis brevis arises from the radius distal to the abductor pollicis longus, from the interosseous membrane, and from the dorsal surface of the radius. [1]

Its direction is similar to that of the abductor pollicis longus, its tendon passing the same groove on the lateral side of the lower end of the radius, to be inserted into the base of the first phalanx of the thumb.

Variation[edit]

Absence; fusion of tendon with that of the extensor pollicis longus.

Function[edit]

In a close relationship to the abductor pollicis longus, the extensor pollicis brevis both extends and abducts the thumb[1] at the carpometacarpal and metacarpophalangeal joints.[2]

Additional images[edit]

Bones of left forearm. Posterior aspect. 
Bones of the left hand. Dorsal surface. 
Tendons of forefinger and vincula tendina. 
Transverse section across distal ends of radius and ulna. 
Transverse section across the wrist and digits. 
The mucous sheaths of the tendons on the back of the wrist. 
The radial and ulnar arteries. 
Arteries of the back of the forearm and hand. 
Extensor carpi radialis brevis muscle 
Extensor pollicis brevis muscle 
Extensor pollicis brevis muscle 
Extensor pollicis brevis muscle 
Extensor pollicis brevis muscle 
Extensor pollicis brevis muscle 
Extensor pollicis brevis muscle 
Extensor pollicis brevis muscle 
Muscle of the hand.Posterior view. 

References[edit]

This article incorporates text from a public domain edition of Gray's Anatomy.

  1. ^ a b Platzer 2004, p. 168
  2. ^ "Thumb Articulations". ExRx.net. Retrieved June 2010. 

Sources[edit]

  • Platzer, Werner (2004). Color Atlas of Human Anatomy, Vol. 1: Locomotor System (5th ed.). Thieme. ISBN 3-13-533305-1. 

External links[edit]