Dorsal Forearm and Dorsum of the Hand

Question 1

Brachioradialis O

Answer 1

proximal two thirds of lateral supraepicondylar ridge of humerus

Question 2

Brachioradialis I

Answer 2

lateral surface of distal end of radius proximal to styloid process

Question 3

Brachioradialis Innervation

Answer 3

radial nerve C5, C6, C7

Question 4

Brachioradialis Action

Answer 4

relatively weak flexion of elbow joint, maximal when forearm is in midpronated position

Question 5

Extensor Carpi Radialis Longus O

Answer 5

lateral supra-epicondylar ridge of humerus

Question 6

Extensor Carpi Radialis Longus I

Answer 6

dorsal aspect of base of 2nd metacarpal

Question 7

Extensor Carpi Radialis Longus Innervation

Answer 7

radial nerve C6, C7

Question 8

Extensor Carpi Radialis Longus Action

Answer 8

extend and abduct wrist joint, extensor carpi radialis brevis active suring fistclenching

Question 9

Extensor Carpi Radialis Brevis O

Answer 9

lateral epicondyle of humerus

Question 10

Extensor Carpi Radialis Brevis I

Answer 10

dorsal aspect of base of 3rd metacarpal

Question 11

Extensor Carpi Radialis Brevis Innervation

Answer 11

deep branch of radial nerve C7, C8

Question 12

Extensor Carpi Radialis Brevis Action

Answer 12

extend and abduct wrist joint, extensor carpi radialis brevis active suring fistclenching

Question 13

Extensor Digitorum O

Answer 13

lateral epicondyle of humerus

Question 14

Extensor Digitorum I

Answer 14

extensor expansions of medial fourfingers

Question 15

Extensor Digitorum Innervation

Answer 15

Posterior interosseous nerve (C7,C8)

Question 16

Extensor Digitorum Action

Answer 16

extend wrist joint

extend medial four fingers primarily at metacarpophalangeal joints, secondarily at interphalangeal joints

Question 17

Extensor Digiti Minimi O

Answer 17

lateral epicondyle of humerus

Question 18

Extensor Digiti Minimi I

Answer 18

extensor expansion of 5th finger

Question 19

Extensor Digiti Minimi Innervation

Answer 19

posterior interosseus nerve (C7, C8) continuation of deep branch of radial nerve

Question 20

Extensor Digiti Minimi Action

Answer 20

extends wrist joint

extends 5th finger primarily at metacarpophalangeal joint, secondarily at interphalangeal joint

Question 21

Extensor carpi Ulnaris O

Answer 21

lateral epicondyle of humerus, posterior border of ulna via a shared aponeurosis

Question 22

Extensor carpi Ulnaris I

Answer 22

dorsal aspect of base of 5th metacarpal

Question 23

Extensor carpi Ulnaris Innervation

Answer 23

posterior interosseus nerve (C7, C8) continuation of deep branch of radial nerve

Question 24

Extensor carpi Ulnaris Action

Answer 24

extends and adducts wrist joint (aslo active during fist clenching)

Question 25

Abductor Pollicis Longus O

Answer 25

posterior surface of proximal halves of ulna, radius, and interossues membrane

Question 26

Abductor Pollicis Longus I

Answer 26

base of 1st metacarpal

Question 27

Abductor Pollicis Longus Innervation

Answer 27

posterior interosseous nerve (C7, C8), continuation of deep branch of radial nerve

Question 28

Abductor Pollicis Longus Action

Answer 28

extends wrist joint

abducts thumb and extends it at carpometacarpal joint

Question 29

Extensor Pollicis Longus O

Answer 29

posterior surface of middle third of ulna and interosseuous membrane

Question 30

Extensor Pollicis Longus I

Answer 30

dorsal aspect of base of distal phalanx thumb

Question 31

Extensor Pollicis Longus Innervation

Answer 31

posterior interosseous nerve (C7, C8), continuation of deep branch of radial nerve

Question 32

Extensor Pollicis Longus Action

Answer 32

extends wrist joint
extends distal phalanx of thumb at interphalangeal joint
extends metacarpophalangeal and carpometacarpal joints

Question 33

Extensor Pollicis Brevis O

Answer 33

posterior surface of distal thirs of radius and interossues membrane

Question 34

Extensor Pollicis Brevis I

Answer 34

dorsal aspect of base of proximal phalanx of thumb

Question 35

Extensor Pollicis Brevis Innervation

Answer 35

posterior interosseous nerve (C7, C8), continuation of deep branch of radial nerve

Question 36

Extensor Pollicis Brevis Action

Answer 36

extends wrist joint
extends proximal phalanx of thumbatmetacarpophalangeal joint
extends carpometacarpal joint

Question 37

Extensor Indicis O

Answer 37

posterior surface of distal third of ulna and interossues membrane

Question 38

Extensor Indicis I

Answer 38

extensor expansion of 2nd finger

Question 39

Extensor Indicis Innervation

Answer 39

posterior interosseous nerve (C7, C8), continuation of deep branch of radial nerve

Question 40

Extensor Indicis Action

Answer 40

extend wrist joint
extends 2ndfinger
helps extend hand at wrist

Question 41

Supinator O

Answer 41

lateral epicondyle of humerus
radial collateral and anular ligaments
supinator fossa
crest of ulna

Question 42

Supinator I

Answer 42

lateral, posterior, and anterior surfaces of proximal third of radius

Question 43

Supinator Innervation

Answer 43

deep branch of radial nerve (C7, C8)

Question 44

Supinator Action

Answer 44

supinates forearm

rotates radius to turn palm anteriorly or superiroly (if elbow is flexed)