Extensor digitorum
Musculus extensor digitorum
MuscularSuperficial musclesArmLeft and right
View left in 3D View right in 3D
- What it is
- Arises from the common extensor origin on the lateral epicondyle; its belly divides into four tendons that cross the back of the hand to the extensor expansions of the index to little fingers.
- Function
- Extends the fingers at the knuckle and, via the expansions, the finger joints; helps extend the wrist.
- Size
- About 25 cm to the knuckles; tendons ~2 mm thick.
- Clinical note
- Its tendons are linked by juncturae tendinum on the back of the hand, which is why the ring finger cannot be lifted fully on its own. The tendons are shown only as far as the knuckles.