Muscles of Forearm (Posterior Compartment)

Question 1

Brachioradialis - Attachments

Answer 1

FROM
*lateral supracondylar ridge of the humerus

TO
*distal radius lateral to the styloid process

Question 2

Brachioradialis - Actions

Answer 2

flexes the elbow

Question 3

Brachioradialis - Innervation

Answer 3

Radial Nerve
C5-6

Question 4

Extensor carpi radialis brevis - Attachments

Answer 4

FROM
*lateral epicondyle of the humerus (common extensor origin) to

TO
*base of the 3rd metacarpal

Question 5

Extensor carpi radialis brevis - Actions

Answer 5

extends & abducts hand at wrist (radial deviation)

Question 6

Extensor carpi radialis brevis - Innervation

Answer 6

Radial Nerve
C6-8

Question 7

Extensor carpi radialis longus - Attachments

Answer 7

FROM
*lateral supracondylar ridge of the humerus

TO
*base of the 2nd metacarpal

Question 8

Extensor carpi radialis longus - Actions

Answer 8

*extends & abducts hand at wrist (radial deviation)
*assists in flexion of the elbow

Question 9

Extensor carpi radialis longus - Innervation

Answer 9

Radial Nerve
C6-8

Question 10

Extensor carpi ulnaris - Attachments

Answer 10

FROM
*lateral epicondyle of the humerus (common extensor origin)

TO
*base of the 5th metacarpal

Question 11

Extensor carpi ulnaris - Actions

Answer 11

extends & adducts hand at wrist (ulnar deviation)

Question 12

Extensor carpi ulnaris - Innervation

Answer 12

Radial Nerve
C6-8

Question 13

Extensor digitorum - Attachments

Answer 13

FROM
*lateral epicondyle of the humerus (common extensor origin)

TO
*extensor expansions of digits 2-5

Question 14

Extensor digitorum - Actions

Answer 14

*extends phalanges (primarily at metacarpophalangeal, secondarily at interphalangeal)
*extends hand at wrist

Question 15

Extensor digitorum - Innervation

Answer 15

Radial Nerve
C6-8

Question 16

Extensor digiti minimi - Attachments

Answer 16

FROM
*lateral epicondyle of the humerus (common extensor origin)

TO
*digital expansion of the 5th digit

Question 17

Extensor digiti minimi - Actions

Answer 17

extends 5th digit (metacarpophalangeal & interphalangeal)

Question 18

Extensor digiti minimi - Innervation

Answer 18

Radial Nerve
C7-8

Question 19

Abductor pollicis longus - Attachments

Answer 19

FROM
*proximal posterior radius, ulna & interosseous membrane

TO
*base of the 1st metacarpal & trapezium

Question 20

Abductor pollicis longus - Actions

Answer 20

*abducts & extends thumb at carpometacarpal joint
*abducts hand at wrist (radial deviation)

Question 21

Abductor pollicis longus - Innervation

Answer 21

Radial Nerve
C6-8

Question 22

Extensor indicis - Attachments

Answer 22

FROM
*posterior surface of the ulna & interosseous membrane

TO
*digital expansion of the 2nd digit

Question 23

Extensor indicis - Actions

Answer 23

extends 2nd digit (metacarpophalangeal & interphalangeal)

Question 24

Extensor indicis - Innervation

Answer 24

Radial Nerve
C7-8

Question 25

Extensor pollicis brevis - Attachments

Answer 25

FROM *posterior radial surface & interosseous membrane TO *base of the 1st proximal phalanx

Question 26

Extensor pollicis brevis - Actions

Answer 26

*extends thumb (metacarpophalangeal) *extends & abducts CMC joint

Question 27

Extensor pollicis brevis - Innervation

Answer 27

Radial Nerve C6-8

Question 28

Extensor pollicis longus - Attachments

Answer 28

FROM *middle 1/3rd of the posterior surface of the ulna & interosseous membrane TO *base of the 1st distal phalanx

Question 29

Extensor pollicis longus - Actions

Answer 29

extends thumb (CMC & metacarpophalangeal & interphalangeal)

Question 30

Extensor pollicis longus - Innervation

Answer 30

Radial Nerve C6-8

Question 31

Supinator - Attachments

Answer 31

FROM *lateral epicondyle of the humerus, radial collateral ligament & supinator crest of the ulna TO *lateral surface of the proximal radius

Question 32

Supinator - Actions

Answer 32

supinates forearm

Question 33

Supinator - Innervation

Answer 33

Radial Nerve C5-6