Extensor Digitorum
Musculus extensor digitorum
Extensor digitorum is the main extensor of the four fingers, opening the hand and balancing the powerful finger flexors to maintain joint health and grip control. Its tendons are visible on the back of the hand and are trained directly by finger-extension (rubber-band or extensor) work, which is commonly prescribed to offset heavy flexor loading. Its common origin is a contributor to lateral epicondylitis.
- Actions
- Extension of the metacarpophalangeal and interphalangeal joints of digits 2-5, Assists wrist extension
- Origin
- Lateral epicondyle of the humerus via the common extensor tendon
- Insertion
- Extensor expansions of the second to fifth digits, reaching the middle and distal phalanges
- Innervation
- Deep branch of the radial nerve / posterior interosseous nerve (C7-C8)
- Blood supply
- Posterior interosseous artery
Exercises (5)
Trains as a primary mover
Assists in