muscles of the forearm

Question 1

Pronator teres

Answer 1

O: medial epicondyle of humerus, coronoid process of ulna

I: lateral surface of radius

Question 2

Flexor carpi ulnaris

Answer 2

O: medial epicondyle of humerus, olecranon and posterior border of the ulna

I: pisiform, hamate, base of metacarpal 5

Question 3

Flexor carpi radialis

Answer 3

O: medial epicondyle of the humerus

I: base of metacarpals 2 and 3

Question 4

Palmaris longus

Answer 4

O: medial epicondyle of the humerus

I: palmar aponeurosis of the hand, flexor retinaculum of the wrist

Question 5

Flexor digitorum superficialis

Answer 5

O: medial epicondyle of the humerus, coronoid process of the ulna, anterior surface of the radius

I: middle phalanges of digits 2-5 (splits into 4 tendons)

Question 6

Flexor digitorum profundus

Answer 6

O: anterior surface of the ulna, interosseous membrane of the forearm

I: distal phalanges of digits 2-5 (splits into 4 tendons)

Question 7

Flexor pollicis longus

Answer 7

O: anterior surface of the radius, interosseous membrane of the forearm

I: distal phalanx of the thumb

Question 8

Pronator quadratus

Answer 8

O: anterior aspect of the ulna

I: anterior aspect of the radius

Question 9

Innervation of the anterior compartment?

Answer 9

Median nerve, except:
- flexor carpi ulnaris (ulnar nerve)
- ulnar part of flexor digitorum profundus (ulnar nerve)

Question 10

List the 6 superficial muscles of the posterior compartment of the forearm.

Answer 10

Brachioradialis, extensor carpi radialis longus, extensor carpi radialis brevis, extensor digitorum, extensor digiti minimi, extensor carpi ulnaris

Question 11

Innervation of the posterior compartment?

Answer 11

Radial nerve, deep radial nerve (of radial), posterior interosseous nerve (of radial)

Question 12

Brachioradialis

Answer 12

O: lateral supracondylar ridge of the humerus

I: styloid process of the radius

Question 13

Extensor carpi radialis longus

Answer 13

O: lateral supracondylar ridge of the humerus

I: base of metacarpal 2

Question 14

Extensor carpi radialis brevis

Answer 14

O: lateral epicondyle of the humerus

I: base of metacarpal 3

Question 15

Extensor digitorum

Answer 15

O: lateral epicondyle of the humerus

I: extensor expansions of digits 2-5

Question 16

Extensor digiti minimi

Answer 16

O: lateral epicondyle of the humerus

I: extensor expansion of digit 5

Question 17

Extensor carpi ulnaris

Answer 17

O: lateral epicondyle of the humerus, posterior border of the ulna

I: base of metacarpal 5

Question 18

List the 5 deep muscles of the posterior compartment of the forearm.

Answer 18

Supinator, abductor pollicis longus, extensor pollicis longus, extensor pollicis brevis, extensor indicis

Question 19

Supinator

Answer 19

O: lateral epicondyle of the humerus, supinator fossa and supinator crest of the ulna

I: posterior, lateral, and anterior aspects of the radius (wrapping around)

Question 20

Abductor pollicis longus

Answer 20

O: posterior surface of the ulna and radius, interosseous membrane

I: base of metacarpal 1 (tendon forms lateral border of anatomical snuff box), trapezium

Question 21

Extensor pollicis longus

Answer 21

O: posterior surface of the ulna, interosseous membrane

I: base of distal phalanx of the thumb (tendon forms the medial border of anatomical snuff box)

Question 22

Extensor pollicis brevis

Answer 22

O: posterior surface of the radius, interosseous membrane

I: base of proximal phalanx of the thumb (tendon forms lateral border of anatomical snuff box)

Question 23

Extensor indicis

Answer 23

O: posterior surface of the ulna, interosseous membrane

I: extensor expansion of digit 2