The abductor pollicis brevis muscle is a flat & thin muscle located just under the skin. It is a thenar muscle and consequently contributes to the bulk of the palm’s thenar eminence.
Attachment of the Abductor Pollicis Brevis
Origin: The abductor pollicis brevis muscle originates from the flexor retinaculum of the hand, the tubercle of the scaphoid bone, and additionally sometimes from the tubercle of the trapezium bone.
Insertion: Moving lateralward and downward, it is inserted by 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 of the Abductor Pollicis Brevis
The abductor pollicis brevis is innervated by the recurrent branch of the median nerve (C8 and T1)
Arterial Supply of the Abductor Pollicis Brevis
Superficial palmar branch of the radial artery
Function of the Abductor Pollicis Brevis
Abducts thumb and helps also assists in opposition and extension of the thumb.
