has muscle origin interosseous muscle of manus dorsal interosseous of manus dorsal interosseous muscle of hand Action: abducts medial digits SCTID:245002007 NCIT:C52703 UBERON:0001503 MA:0002314 dorsal interosseous of hand Wikipedia:Dorsal_interossei_muscles_(hand) dorsal manus interosseous muscle The dorsal interossei of the hand are muscles that occupy the space between the metacarpals. There are four dorsal interossei in each hand. They are specified as 'dorsal' to contrast them with the palmar interossei, which are located on the anterior side of the metacarpals. The dorsal interosseous muscles are bipennate, with each muscle arising by two heads from the adjacent sides of the metacarpal bones, but more extensively from the metacarpal bone of the finger into which the muscle is inserted. They are inserted into the bases of the proximal phalanges and into the extensor expansion of the corresponding extensor digitorum tendon. The middle digit has two dorsal interossei insert onto it while the first digit (thumb) and the fifth digit (little finger) have none[WP]. musculi interossei dorsales manus FMA:37418 dorsal hand interosseus muscle metacarpus skeleton