Thenar eminence muscle :-
Abductor pollicis brevis muscle :-
Muscle details :-
- The abductor pollicis brevis is a flat, thin muscle located just under the skin. It is a thenar muscle, and therefore contributes to the bulk of the palm’s thenar eminence.
- the flexor retinaculum of the hand, the tubercle of the scaphoid bone, and additionally sometimes from the tubercle of the trapezium.
- a thin, flat tendon into the lateral side of the base of the first phalanx of the thumb and the capsule of the metacarpophalangeal joint.
Nerve supply :-
- The abductor pollicis brevis is innervated by the recurrent branch of the median nerve (Roots C5- C7 and C8-T1 in the brachial plexus lateral and medial cords respectively) .
- Abduction of the thumb is defined as the movement of the thumb anteriorly, a direction perpendicular to the palm. The abductor pollicis brevis does this by acting across both the carpometacarpal joint and the metacarpophalangeal joint.
- It also assists in opposition and extension of the thumb.