Abductor pollicis longus muscle

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Abductor pollicis longus muscle
Front of right upper extremity. (Abductor pollicis longus labeled at upper left.)
The mucous sheaths of the tendons on the back of the wrist. (Abductor pollicis longus and brevis visible at center right, going into thumb.)
Latin	musculus abductor pollicis longus
Gray's	subject #125 455
Origin	ulna, radial styloid process
Insertion	first metacarpal
Artery:
Nerve:	Posterior interosseous nerve
Action:	abduction, extension of thumb
Antagonist:	Adductor pollicis muscle
Dorlands /Elsevier	m_22/12548315

The Abductor pollicis longus lies immediately below the Supinator and is sometimes united with it.

Contents 1 Origin and insertion 2 Action 3 Variations 4 See also 5 Additional images 6 External links

[edit] Origin and insertion

It arises from the lateral part of the dorsal surface of the body of the ulna below the insertion of the Anconæus, from the interosseous membrane, and from the middle third of the dorsal surface of the body of the radius.

Passing obliquely downward and lateralward, it ends in a tendon, which runs through a groove on the lateral side of the lower end of the radius, accompanied by the tendon of the Extensor pollicis brevis, and is inserted into the radial side of the base of the first metacarpal bone.

It occasionally gives off two slips near its insertion: one to the greater multangular bone and the other to blend with the origin of the Abductor pollicis brevis.

[edit] Action

The chief action of the Abductor pollicis longus is to carry the thumb laterally from the palm of the hand.

By its continued action it helps to extend and abduct the wrist.

[edit] Variations

More or less doubling of muscle and tendon with insertion of the extra tendon into the first metacarpal, the greater multangular, or into the Abductor pollicis brevis or Opponens pollicis.

[edit] See also

• Anatomical snuffbox
• Extensor pollicis longus

[edit] Additional images

Anatomical snuff box	Bones of left forearm. Posterior aspect.	Bones of the left hand. Volar surface.	Tendons of forefinger and vincula tendina.
Cross-section through the middle of the forearm.	Posterior surface of the forearm. Superficial muscles.	Posterior surface of the forearm. Deep muscles.	Transverse section across distal ends of radius and ulna.
Transverse section across the wrist and digits.	The muscles of the thumb.	The radial and ulnar arteries.	Deep palmar nerves.

[edit] External links

• LUC abpl
• 731512832 at GPnotebook
• Abductor+pollicis+longus+muscle at eMedicine Dictionary
• PTCentral

v • d • e List of muscles of upper limbs VERTEBRAL COLUMN trapezius - latissimus dorsi - rhomboid (major, minor) - levator scapulae THORACIC WALLS pectoralis major - pectoralis minor - subclavius - serratus anterior SHOULDER deltoid - rotator cuff (supraspinatus, infraspinatus, teres minor, subscapularis) - teres major ARM anterior compartment: coracobrachialis - biceps brachii - brachialis posterior compartment: triceps brachii - anconeus FOREARM anterior compartment: superf. - pronator teres - palmaris longus - flexor carpi radialis - flexor carpi ulnaris - flexor digitorum superficialis anterior compartment: deep - pronator quadratus - flexor digitorum profundus - flexor pollicis longus posterior compartment: superf. - mobile wad (brachioradialis, extensor carpi radialis longus and brevis) - extensor digitorum, - extensor digiti minimi - extensor carpi ulnaris posterior compartment: deep - supinator - anatomical snuff box (abductor pollicis longus, extensor pollicis brevis, extensor pollicis longus) - extensor indicis HAND lateral volar - thenar (opponens pollicis, flexor pollicis brevis, abductor pollicis brevis) - adductor pollicis medial volar - hypothenar (opponens digiti minimi, flexor digiti minimi brevis, abductor minimi digiti) - palmaris brevis intermediate - lumbrical - interossei (dorsal, palmar)