Dorsal Forearm

Question 0

Extensor carpi radialis longus

Answer 0

PA: lateral supra-epicondylar ridge of humerus
DA: dorsal aspect of base 2nd metacarpal
N: Radial N. (C6,7)
MA: extends and abduct wrist joint

Question 1

Brachioradialis

Answer 1

PA: proximal 2/3 of lateral supraepicondylar ridge
DA: lateral surface of distal end of radius
N: radial nerve (C5,6,7)
MA: weak flexion of elbow (maximum flexion when midpronated)

Question 2

Extensor carpi radialis brevis

Answer 2

PA: lateral epicondyle of humerus
DA: Dorsal aspect of base of 3rd meta carpal
N: deep branch of radial nerve (C7,C8)
MA: extend and abduct wrist joint; active during fist clenching

Question 3

extensor digitorum

Answer 3

PA: lateral epicondyle of humerus
DA: extensor expansion of middle 4 fingers
N: posterior interosseous N. (C7,C8) continuation of deep branch of radial nerve
MA: extend wrist; extends 4 fingers

Question 4

extensor digiti minimi

Answer 4

PA: lateral epicondyle of humerus
DA: extensor expansion of 5th finger
N: Posterior interosseous N (C7,8) continuation of deep branch of radial nerve
MA: extend wrist; extend 5th finger

Question 5

extensor carpi ulnaris

Answer 5

PA: lateral epicondyle of humerus
DA: dorsal aspect of base of 5th metacarpal
N: posterior interosseous N. (C7,8), continuation of deep branch of radial N.
MA: extends and adducts wrist (also active during fist clenching)

Question 6

supinator

Answer 6

PA: lateral epicondyle of humerus, radial collateral and anular ligaments, supinator fossa, crest of ulna
DA: lateral, posterior and anterior surfaces of proximal third of radius
N: deep branch of radial N. (C7,8)
MA: supinates forearm

Question 7

abductor pollicis longus

Answer 7

PA: posterior surface of proximal halves of ulna, radius, and interosseous membrane
DA: base of 1st metacarpal
N: posterior interosseous N. (C7,8), continuation of deep branch of radial N.
MA: extends wrist; abducts and extends thumb

Question 8

extensor pollicis longus

Answer 8

PA: posterior surface of middle 1/3 of ulna and interosseous membrane
DA: base of distal phalanx of thumb
N: posterior interosseous N. (C7,8), continuation of deep branch of radial N.
MA: extends wrist; extends distal phalanx of thumb

Question 9

extensor pollicis brevis

Answer 9

PA: posterior surface of distal 1/3 of radius and interosseous membrane
DA: proximal phalanx of thumb
N: posterior interosseous N. (C7,8), continuation of deep branch of radial N.
MA: extends wrist; extends proximal phalanx of thumb

Question 10

extensor indicis

Answer 10

PA: posterior surface of distal 1/3 of ulna and interosseous membrane
DA: extensor expansion of 2nd finger
N: posterior interosseous N. (C7,8), continuation of deep branch of radial N.
MA: extends wrist; extends 2nd finger, helps extend hand at wrist