Origins of Muscles of the Forearm

Question 1

What are the origins of pronator teres?

Answer 1

Humeral head: medial epicondyle of the humerus (above CFO)
Ulnar Head: coronoid process of the ulna (med surface).

Question 2

What is the origin of flexor carpi radialis (FCR)?

Answer 2

Medial epicondyle of humerus via the common flexor tendon

Question 3

What is the origin of palmaris longus (PL)?

Answer 3

Medial epicondyle of humerus via common flexor tendon

Question 4

What are the origins of flexor carpi ulnaris (FCU)?

Answer 4

Humeral head: medial epicondyle via the common flexor tendon.

Ulnar head: olecranon and posterior border of ulna (superior 2/3)

Question 5

What are the origins of flexor digitorum superficialis (FDS)?

Answer 5

Humeroulnar head: Medial epicondyle of humerus and coronoid process of ulna (medial side)

Radial head: Oblique line of radius (anterior surface)

Question 6

What is the origin of flexor digitorum profundus (FDP)?

Answer 6

Proximal 2/3 of anterior surface of ulna and interosseus membrane

Question 7

What is the origin of flexor pollicis longus (FPL)

Answer 7

Anterior surface of radius (middle 1/2), interosseus membrane.

Question 8

What is the origin of pronator quadratus? (PQ)

Answer 8

Distal 1/4 of the anterior surface of ulna

Question 9

What is the origin of brachioradialis? (BR)

Answer 9

Lateral supracondylar ridge of the humerus (and lateral intermuscular septum)

Question 10

What is the origin of extensor carpi radialis longus? (ECRL)

Answer 10

Distal 1/3 of the lateral supracondylar ridge of the humerus

Question 11

What is the origin of extensor carpi radialis brevis? (ECRB)

Answer 11

Lateral epicondyle of humerus via common extensor tendon

Question 12

What is the origin of extensor digitorum? (ED)

Answer 12

Lateral epicondyle of humerus via common extensor tendon

Question 13

What is the origin of extensor digiti minimi? (EDM)

Answer 13

Lateral epicondyle of humerus via common extensor tendon.

Question 14

What is the origin of extensor carpi ulnaris? (ECU)

Answer 14

Lateral epicondyle of humerus via common extensor tendon and posterior border of the ulna

Question 15

What is the origin of Supinator?

Answer 15

Lateral epicondyle of humerus, radial collateral and annular ligaments, and the supinator crest of the ulna

Question 16

What is the origin of abductor pollicis longus? (APL)

Answer 16

Posterior surface of middle of radius and ulna and interosseus membrane

Question 17

What is the origin of extensor pollicis longus? (EPL)

Answer 17

Middle 1/3 of the posterior surface of the ulna and the interosseus membrane (distal to AbdPL)

Question 18

What is the origin of extensor pollicis brevis? (EPB)

Answer 18

Posterior surface of the middle of the radius and interosseus membrane (distal to AbdPL)

Question 19

What is the origin of extensor indicis? (EI)

Answer 19

Distal posterior surface of the ulna and interosseus membrane

Question 20

What is the origin of abductor pollicis brevis?

Answer 20

flexor retinaculum, scaphoid, and tubercle of the trapezium.

Question 21

What is the origin of opponens pollicis?

Answer 21

flexor retinaculum and trapezium

Question 22

What is the origin of flexor pollicis brevis?

Answer 22

flexor retinaculum and trapezium

Question 23

What are the origins of adductor pollicis?

Answer 23

oblique head: capitate and bases of metacarpals 2 and 3.

transverse head: 3rd metacarpal - anterior surface (palmar)

Question 24

What is the origin of palmaris brevis?

Answer 24

flexor retinaculum and palmar aponeurosis

Question 25

What is the origin of abductor digiti minimi?

Answer 25

pisiform

Question 26

What is the origin of flexor digiti minimi brevis?

Answer 26

flexor retinaculum and hook of the hamate

Question 27

What is the origin of opponens digiti minimi?

Answer 27

flexor retinaculum and hook of the hamate

Question 28

What is the origin of lumbricales?

Answer 28

tendons of flexor digitorum profundus (off lateral aspect of 2nd-5th tendons and off medial aspect of 3rd and 4th tendons also.

Question 29

What is the origin of dorsal interosseii?

Answer 29

adjacent sides of the shaft of the metacarpals (2 heads)

Question 30

What is the origin of palmar interosseii?

Answer 30

palmar medial surface of 2nd metacarpal and palmar lateral surface of 4th and 5th metacarpal (1 head)