Name Extensor pollicis brevisPronunciation (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)) | 
