Extensor Pollicis Brevis

Question 1

Extensor Pollicis Brevis (ORIGIN)

Answer 1

Posterior surface of the distal third of the radius and interosseous membrane

Question 2

Extensor Pollicis Brevis (INSERTION)

Answer 2

Base of the proximal phalanx of the thumb

Question 3

Extensor Pollicis Brevis (INNERVATION)

Answer 3

Radial nerve (posterior interosseous nerve, C7, C8)

Question 4

Extensor Pollicis Brevis (BLOOD SUPPLY)

Answer 4

Posterior interosseous artery

Question 5

Extensor Pollicis Brevis (ACTION)

Answer 5

Extends the proximal phalanx of the thumb at the metacarpophalangeal joint; extends the carpometacarpal joint