abductor pollicis longus muscle


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abductor pollicis longus muscle

A long hand muscle that abducts the thumb, which arises from the dorsolateral surface of the ulna.
 
Action
Moves thumb anteriorly (from anatomic position of the body in space) toward the base of the fifth finger.

Critical for
Thumb manoeuvrability, precision and power grip.

Nerve
Posterior interosseous nerve—a continuation of the deep branch of the radial nerve.

Origin
Lateral dorsal surface of the body of the ulna below the anconeus insertion, from the interosseous membrane, and the middle third of the dorsal surface of the body of the radius.

Insertion
Radial side of the base of the first metacarpal bone.

ab·duc·tor pol·li·cis long·us mus·cle

(ab-dŭk'tŏr pol'li-sis long'gŭs mŭs'ĕl)
Outcropping muscle of posterior compartment of forearm; origin, interosseous membrane and posterior surfaces of radius and ulna; insertion, lateral side of base of first metacarpal bone; action, abducts and assists in extending thumb; nerve supply, radial.
Synonym(s): long abductor muscle of thumb, musculus abductor pollicis longus, musculus extensor ossis metacarpi pollicis.