Abductor pollicis brevis
Abductor pollicis brevis - Definition
The abductor pollicis brevis is a flat, thin muscle that belong to the thenar group of hand muscles. It is also called:
Abductor pollicis brevis - Location
It can be found just beneath the skin of an area near the thumb in the human body.
Abductor pollicis brevis - Origin and Insertion
The muscle has its origin in:
The muscle runs laterally and downwards, and is inserted by a flat, thin tendon on radial side at the base of proximal phalanx and the extensor expansion of the thumb.
Abductor pollicis brevis - Innervation
The recurrent branch of the median nerve (T1 and C8) innervates this muscle. It is supplied blood by the superficial palmar branch of the radial artery as well as a tiny muscular branch of the radial artery.
Abductor pollicis brevis - Functions
It acts as an abductor and draws the thumb away from the palm. It also helps in the extension and opposition of the thumb. As it belongs to the thenar group, the muscle also adds to the volume of thenar eminence of the palm.
Abductor pollicis brevis - Pain and Disorders
Those suffering from repetitive motion injuries to this muscle may experience pain, inflammation and soreness. A swollen abductor pollicis brevis can cause stiffness and difficulty in thumb movement. Acute inflammation may cause inability to rotate thumb, and severe disability as a consequence. Carpal thunnel syndrome often involves this thumb muscle.
Abductor pollicis brevis - Pictures
The images underneath show the position and appearance of the muscle in the human body.
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