Name

# Extensor Pollicis Brevis

Pronunciation

(eks-TEN-sor POL-uh-sus BREV-is)

Origin/Proximal Attachment

Posterior surface of radius (below abductor pollicis longus) Interosseous membraneAntebrachial fascia

Insertion/Distal Attachment

Base of proximal phalanx of thumb

Action/Relevance

Extends the proximal phalanx & 1st metacarpal of the thumbRadially deviates the hand at the wrist

Innervation

Radial nerve - posterior interosseous (C6, 7+/-8))

Notes

Short muscle for extension of thumb. Origin: dorsal surface of radius and interosseous membrane of the forearm . Insertion: dorsal aspect of the base of the proximal phalanx of the thumb.