dorsal interosseous manus

Introduction

One of 4 intrinsic muscles of the hand.

Origin

sides of the adjacent metacarpal bones

Insertion

(proximal phalanges & extensor expansion)

• 1st: into radial side of index finger
• 2nd: into radial side of middle finger
• 3rd: into ulnar side of middle finger
• 4th: into ulnar side of ring finger

Action

abducts fingers 2-4 from an axis through the middle finger

Innervation

ulnar nerve

More general terms

• skeletal muscle (voluntary muscle)