Posterior Forearm Muscles

Question 1

Origin of the brachioradialis

Answer 1

Proximal 2/3 of lateral supracondylar ridge of humerus

Question 2

Insertion of the brachioradialis

Answer 2

Lateral surface of distal end of radius, proximal to styloid process

Question 3

What does the brachioradialis do?

Answer 3

Flexes the forearm at the elbow joint

Question 4

What innervates the brachioradialis?

Answer 4

Radial nerve

Question 5

Origin of the extensor carpi radialis longus

Answer 5

Lateral supracondylar ridge of humerus

Question 6

Insertion of the extensor carpi radialis longus

Answer 6

Base of 2nd metacarpal

Question 7

What does the extensor carpi radialis longus do?

Answer 7

Extend and abduct hand at wrist joint

Question 8

What innervates the extensor carpi radialis longus?

Answer 8

Radial nerve

Question 9

Origin of the Extensor Carpi Radialis Brevis

Answer 9

Lateral epicondyle of humerus

Question 10

Insertion of the Extensor Carpi Radialis Brevis

Answer 10

Base of 3rd metacarpal

Question 11

What does the Extensor Carpi Radialis Brevis do?

Answer 11

Extend and abduct (radial deviation) hand at wrist joint

Question 12

What innervates the Extensor Carpi Radialis Brevis?

Answer 12

Radial nerve

Question 13

Origin of the Extensor Digitorum

Answer 13

Lateral epicondyle of humerus

Question 14

Insertion of the Extensor Digitorum

Answer 14

Extensor expansions of medial four digits

Question 15

What does the extensor digitorum do?

Answer 15

Extends medial four digits at metacarpophalangeal joints

Extends hand at wrist joint

Question 16

What innervates the extensor digitorum?

Answer 16

Radial nerve

Question 17

Origin of the extensor digitorum minimi

Answer 17

Lateral epicondyle of humerus

Question 18

Insertion of the extensor digitorum minimi

Answer 18

Extensor expansion of 5th digit

Question 19

What does the extensor digitorum minimi do?

Answer 19

Extends 5th digit at metacarpophalangeal and interphalangeal joints

Question 20

What innervates the extensor digitroum minimi?

Answer 20

Radial nerve

Question 21

Origin of the extensor carpi ulnaris

Answer 21

Lateral epicondyle of humerus

Posterior border of ulna

Question 22

Insertion of the extensor carpi ulnaris

Answer 22

Base of 5th metacarpal

Question 23

What does the extensor carpi ulnaris do?

Answer 23

Extends and adducts (ulnar deviation) hand at wrist joint

Question 24

What innervates the extensor carpi ulnaris?

Answer 24

Radial nerve

Question 25

Origin of the supinator

Answer 25

Lateral epicondyle of humerus Radial collateral and annular ligaments Supinator fossa Crest of ulna

Question 26

Insertion of the supinator

Answer 26

Lateral, posterior and anterior surfaces of proximal third of radius

Question 27

What does the supinator do?

Answer 27

Supinates forearm (i.e. rotates radius to turn palm anteriorly)

Question 28

What innervates the supinator?

Answer 28

Radial nerve

Question 29

Origin of the extensor indicis

Answer 29

Posterior surface of ulna and interosseous membrane

Question 30

Insertion of the extensor indicis

Answer 30

Extensor expansion of 2nd digit

Question 31

What does the Extensor Indicis do?

Answer 31

Extends 2nd digit and helps to extend hand

Question 32

What innervates the extensor indicis?

Answer 32

Radial nerve

Question 33

Origin of the abductor pollicis longus

Answer 33

Posterior surface of proximal ½ of ulna, radius and interosseous membrane

Question 34

Insertion of the abductor pollicis longus

Answer 34

Base of 1st metacarpal

Question 35

What does the abductor pollicis longus do?

Answer 35

Abducts thumb and extends it at carpometacarpal joint

Question 36

What innervates the abductor pollicis longus?

Answer 36

Radial nerve

Question 37

Origin of the extensor pollicis longus

Answer 37

Posterior surface of middle third of ulna and interosseous membrane

Question 38

Insertion of the extensor pollicis longus

Answer 38

Base of distal phalanx of thumb

Question 39

What does the extensor pollicis longus do?

Answer 39

Extends distal phalanx of thumb at carpometacarpal and interphalangeal joints

Question 40

What innervates the extensor pollicis longus?

Answer 40

Radial nerve

Question 41

Origin of the extensor pollicis brevis

Answer 41

Posterior surface of distal third of radius and interosseous membrane

Question 42

Insertion of the extensor pollicis brevis

Answer 42

Base of proximal phalanx of thumb

Question 43

What does the extensor pollicis brevis do?

Answer 43

Extends proximal phalanx of thumb at carpometacarpal joint

Question 44

What innervates the extensor pollicis brevis?

Answer 44

Radial nerve