Extensor digiti minimi muscle
| Extensor digiti minimi | |
|---|---|
 The mucous sheaths of the tendons on the back of the wrist. (Extensor digiti quinti proprius labeled at center left.) | |
| Details | |
| Origin | the anterior portion of the lateral epicondyle of the humerus (common extensor tendon) |
| Insertion | at the extensor expansion, located at the base of the proximal phalanx of digit V on the dorsal side |
| Artery | posterior interosseous artery |
| Nerve | posterior interosseous nerve (C7, 8) |
| Actions | extends the little finger at all joints |
| Antagonist | Flexor digiti minimi brevis |
| Identifiers | |
| Latin | musculus extensor digiti minimi |
| TA98 | A04.6.02.044 |
| TA2 | 2506 |
| FMA | 38503 |
| Anatomical terms of muscle | |
The extensor minimi digiti (extensor digiti quinti proprius) is a slender muscle of the forearm, placed on the ulnar side of the Extensor digitorum communis, with which it is generally connected.
It arises from the common Extensor tendon by a thin tendinous slip, from the intermuscular septa between it and the adjacent muscles.
Its tendon runs through a compartment of the dorsal carpal ligament behind the distal radio-ulnar joint, then divides into two as it crosses the hand, and finally joins the expansion of the Extensor digitorum communis tendon on the dorsum of the first phalanx of the little finger.
Variations
An additional fibrous slip from the lateral epicondyle; the tendon of insertion may not divide or may send a slip to the ring finger.
Absence of muscle rare; fusion of the belly with the Extensor digitorum communis not uncommon.
Additional images
-
Bones of left forearm. Posterior aspect. -
Posterior surface of the forearm. Superficial muscles. -
Transverse section across distal ends of radius and ulna. -
Transverse section across the wrist and digits.
External links
- Template:MuscleLoyola
- Illustration: extdigitiminimi from The Department of Radiology at the University of Washington
- Hand kinesiology at the University of Kansas Medical Center
This article incorporates text in the public domain from page 451 of the 20th edition of Gray's Anatomy (1918)