Extensor pollicis brevis
The extensor pollicis brevis muscle is located on the dorsal side of the forearm. It originates from the trapezium and the flexor retinaculum. It is connected with the extensor pollicis longus to make up the interosseous membrane. It inserts at the base of the proximal phalanx of the thumb. This muscle also forms the radial side of the anatomical snuff box at the wrist. Working with the extensor pollicis longus, this muscle allows the thumb, wrist, and fingers to straighten and bend. It gets its nerve supply from the posterior interosseus nerve. Its arterial supply comes from the posterior interosseous artery.
In Depth: Extensor pollicis brevis
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