Opponens pollicis muscle

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Opponens pollicis muscle
Musculusopponenspollicis.png
origin
Flexor retinaculum and trapezium
approach
Lateral side of the first metacarpal
function
Rotation of the thumb towards the palm of the hand
Innervation
Median nerve
Spinal segments
C6-C8

The opponens pollicis muscle ( Latin for "counterpart of the thumb") is one of the muscles of the metacarpal in the area of ​​the ball of the thumb . For pets the muscle does not occur.

function

The opponens pollicis muscle, located very laterally on the ball of the thumb ( thenar ), turns the thumb towards the palm of the hand and thus places it opposite the remaining fingers (so-called opposition ). This turns the human hand (in interaction with the medially adjacent flexor pollicis brevis muscle ) into a gripping hand.

This is also made possible by the special anatomy of the thumb (pollex). The proximal articulatio carpometacarpale functions here as a saddle joint with two-dimensional freedom of movement. The thumb is shorter than the other phalanx and has only two free-standing bone elements due to the two basic joints (see wrist ).