Hand interossei
"Part of the "small muscles for idiots" series
"DAB/PAD"
innervation: deep branch of ulnar nerve
| Dorsal interossei: superficially palpable | |
|---|---|
| Action | Abduction of index, middle, and ring fingers at the metacarpophalangeal joints |
| Origin | adjacent sides of metacarpals |
| Insertion | extensor hoods and base of proximal phalanges of index, middle, and ring fingers |
| Innervation | deep branch of ulnar nerve |
Dorsal interosseous muscles are not associated with the thumb or little finger; these digits possess their own abductors. (Netter's Flash Cards 5th ed.)
- i.e., does not insert into proximal phalanges of thumb or 5th finger
| Palmar interossei: the one that's nowhere near the middle finger | |
|---|---|
| Action | Adduction of the thumb, index, ring, and little fingers at the metacarpophalangeal joints |
| Origin | Sides of metacarpals |
| Insertion | extensor hoods of the thumb, index, ring, and little fingers and the proximal phalanx of thumb |
| Innervation | Deep branch of ulnar nerve |