Sources
Help build the largest human-edited directory on the web.
Submit a site - Become an editor
Wikipedia. Licensed under the GNU Free Documentation License.
Are you an expert in this subject? Join the discussion and share your knowledge at Wikipedia.org.
Extensor pollicis longus muscle
From Wikipedia, the free encyclopedia
| Extensor pollicis longus muscle | ||
|---|---|---|
 |
||
| The mucous sheaths of the tendons on the back of the wrist. (Extensor pollicis longus visible at center right.) | ||
| Latin | musculus extensor pollicis longus | |
| Gray's | subject #125 455 | |
| Origin: | ulna | |
| Insertion: | thumb, distal phalanx | |
| Artery: | ||
| Nerve: | posterior interosseus nerve (branching from the radial nerve) | |
| Action: | extension of the thumb (metacarpophalangeal and interphalangeal) | |
| Antagonist: | Flexor pollicis longus muscle, Flexor pollicis brevis muscle | |
| Dorlands/Elsevier | m_22/12548955 | |
The Extensor pollicis longus is much larger than the Extensor pollicis brevis muscle, the origin of which it partly covers.
Contents |
It arises from the lateral part of the middle third of the dorsal surface of the body of the ulna below the origin of the Abductor pollicis longus, and from the interosseous membrane.
It ends in a tendon, which passes through a separate compartment in the dorsal carpal ligament, lying in a narrow, oblique groove on the back of the lower end of the radius.
It then crosses obliquely the tendons of the Extensores carpi radialis longus and brevis, and is separated from the Extensor brevis pollicis by a triangular interval, the anatomical snuff box in which the radial artery is found; and is finally inserted into the base of the last phalanx of the thumb.
The radial artery is crossed by the tendons of the Abductor pollicis longus and of the Extensores pollicis longus and brevis.
The extends the proximal phalanx, and the
Extensor pollicis longus extends the terminal phalanx of the thumb; in combination with the Extensor pollicis brevis, it helps to extend and abduct the wrist.
 Bones of left forearm. Posterior aspect. |
 Bones of the left hand. Dorsal surface. |
 Tendons of forefinger and vincula tendina. |
|
 Cross-section through the middle of the forearm. |
 Posterior surface of the forearm. Superficial muscles. |
 Posterior surface of the forearm. Deep muscles. |
 Transverse section across the wrist and digits. |
 Arteries of the back of the forearm and hand. |
- LUC epl
- 33947649 at GPnotebook
- Extensor+pollicis+longus+muscle at eMedicine Dictionary
- PTCentral
This article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained herein may be outdated. Please edit the article if this is the case, and feel free to remove this notice when it is no longer relevant.
 |
This muscle article is a stub. You can help Wikipedia by expanding it. |