Anatomy, Shoulder and Upper Limb, Hand Opponens Pollicis Muscle

Excerpt

Motor skills of the hand result from many structures working in sync to produce certain motions for daily living. The hands are just a small part of the human body but contribute significantly to the functionality. Even though the hands are only a small part of a human, they are held together by the largest number of bones. Hand movements are influenced by hand and forearm muscles. Opposition is a small hand movement consisting of the thumb touching the tips of the other digits.

Opposition is defined as positioning something near or close to each other. In medicine, the opposition of the hand is a motion created by several muscles, bones, and nerves working in sync. The muscles that create this primary movement are the opponens muscles. There are two opponens muscles; one muscle appears in the thenar eminence and the other in the hypothenar eminence. The action of the thumb touching the tip of the fifth digit takes place from the contraction of both opponens muscles, while the action required for the thumb to touch the second, third, and fourth digits gets produced from several muscles in the hand and forearm. The lumbrical muscles, flexor digitorum superficialis muscle, and the flexor digitorum profundus muscle contract in the second, third, and fourth digits during the opposition of the hand.