Week 2 Extensors

Question 1

Brachioradialis Origin

Answer 1

proximal two thirds of lateral supra-epicondylar ridge of humerus

Question 2

Brachioradialis Insertion

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

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

Question 5

Brachioradialis Arterial Supply

Answer 5

radial recurrent, radial collateral, and radial arteries

Question 6

Extensor Carpi Radialis Longus Origin

Answer 6

lateral supra-epicondylar ridge of humerus

Question 7

Extensor Carpi Radialis Longus Insertion

Answer 7

dorsal aspect of base of 2nd metacarpal

Question 8

Extensor Carpi Radialis Longus Innervation

Answer 8

Radial nerve (C6, C7)

Question 9

Extensor Carpi Radialis Longus Action

Answer 9

extends and abduct wrist joint; extend carpometacarpal joints

Question 10

Extensor Carpi Radialis Longus Arterial Supply

Answer 10

radial recurrent, radial collateral, and radial arteries

Question 11

Extensor Carpi Radialis Brevis Origin

Answer 11

lateral epicondyle of humerus (common extensor origin)

Question 12

Extensor Carpi Radialis Brevis Insertion

Answer 12

dorsal aspect of base of 3rd metacarpal

Question 13

Extensor Carpi Radialis Brevis Innervation

Answer 13

deep branch of radial nerve (C7, C8)

Question 14

Extensor Carpi Radialis Brevis Action

Answer 14

extends and abducts wrist joint, extends carpometacarpal joints (active during first clenching)

Question 15

Extensor Carpi Radialis Brevis Arterial Supply

Answer 15

radial recurrent and radial arteries

Question 16

Extensor Carpi Ulnaris Origin

Answer 16

lateral epicondyle of humerus

Question 17

Extensor Carpi Ulnaris Insertion

Answer 17

dorsal aspect of base of 5th metacarpal

Question 18

Extensor Carpi Ulnaris Innervation

Answer 18

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

Question 19

Extensor Carpi Ulnaris Action

Answer 19

extends and adducts wrist, carpometacarpal joints (active during first clenching)

Question 20

Extensor Carpi Ulnaris Arterial Supply

Answer 20

radial recurrent and posterior interosseous arteries

Question 21

Extensor digitorum Origin

Answer 21

lateral epicondyle of humerus (common extensor origin)

Question 22

Extensor digitorum Insertion

Answer 22

extensor expansions of medial four fingers

Question 23

Extensor digitorum Innervation

Answer 23

Posterior interosseous nerve (C7, C8), continuation of the deep radial nerve

Question 24

Extensor digitorum Action

Answer 24

extends wrist joint, carpometacarpal joints, extends medial four fingers primarily at metacarpophalangeal joints, secondary at interphalangeal joints

Question 25

Extensor digitorum Arterial Supply

Answer 25

radial recurrent, anterior and posterior interosseous arteries

Question 26

Extensor Digiti Minimi Origin

Answer 26

lateral epicondyle of humerus (common extensor origin)

Question 27

Extensor Digiti Minimi Insertion

Answer 27

extensor expansion of 5th finger

Question 28

Extensor Digiti Minimi Innervation

Answer 28

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

Question 29

Extensor Digiti Minimi Action

Answer 29

extends wrist join, carpometacarpal joints, extends 5th finger primarily at metacarpophalangeal joint, secondarily at interphalangeal joint

Question 30

Extensor Digiti Minimi Arterial Supply

Answer 30

radial recurrent, anterior and posterior interosseous arteries

Question 31

Extensor Indicis Origin

Answer 31

posterior surface of distal third of ulna and interosseous membrane

Question 32

Extensor Indicis Insertion

Answer 32

extensor expansion of 2nd finger

Question 33

Extensor Indicis Innervation

Answer 33

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

Question 34

Extensor Indicis Action

Answer 34

extends wrist joint, carpometacarpal joints, extends 2nd finger; helps extend hand at wrist

Question 35

Extensor Indicis Arterial Supply

Answer 35

anterior and posterior interosseous arteries

Question 36

Supinator Origin

Answer 36

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

Question 37

Supinator Insertion

Answer 37

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

Question 38

Supinator Innervation

Answer 38

Deep branch of radial nerve (C7, C8)

Question 39

Supinator Action

Answer 39

supinates forearm, rotates radius to turn palm anteriorly or superiorly

Question 40

Supinator Arterial Supply

Answer 40

radial recurrent, posterior interosseous, and recurrent interosseous arteriesposterior surface of proximal halves of ulna, radius, and interosseous membrane

Question 41

Abductor Pollicis Longus Origin

Answer 41

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

Question 42

Abductor Pollicis Longus Insertion

Answer 42

base of 1st metacarpal

Question 43

Abductor Pollicis Longus Innervation

Answer 43

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

Question 44

Abductor Pollicis Longus Action

Answer 44

extends wrist joint, carpometacarpal joint, abducts thumb and extends thumb at carpometacarpal joint

Question 45

Abductor Pollicis Longus Arterial Supply

Answer 45

anterior and posterior interosseous arteries

Question 46

Extensor Pollicis Longus Origin

Answer 46

posterior surface of middle third of ulna and interosseous membrane

Question 47

Extensor Pollicis Longus Insertion

Answer 47

dorsal aspect of base of distal phalanx of thumb

Question 48

Extensor Pollicis Longus Innervation

Answer 48

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

Question 49

Extensor Pollicis Longus Action

Answer 49

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

Question 50

Extensor Pollicis Longus Arterial Supply

Answer 50

anterior and posterior interosseous arteries

Question 51

Extensor Pollicis Brevis Origin

Answer 51

posterior surface of distal third of radius and interosseous membrane

Question 52

Extensor Pollicis Brevis Insertion

Answer 52

dorsal aspect of base of proximal phalanx of thumb

Question 53

Extensor Pollicis Brevis Innervation

Answer 53

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

Question 54

Extensor Pollicis Brevis Action

Answer 54

extends wrist joint , carpometacarpal joints, extends proximal phalanx of thumb and metacarpophalangeal joint, extends carpometacarpal joint

Question 55

Extensor Pollicis Brevis Arterial Supply

Answer 55

anterior and posterior interosseous arteries