Muscles of the Antebrachium

Question 1

Flexor Digitorum Superficialis

Answer 1

Origin: Medial epicondyle of humerus, coronoid process of ulna
Insertion: side of middle phalanges 2-5
Action: flex wrist, flex MCP and PIP 2-5, (flex elbow)
Innervation: Median N

Question 2

Flexor Carpi Radialis

Answer 2

Origin: Medial epicondyle of humerus
Insertion: Base of 2nd MC
Action: Flex wrist, radially deviate
Innervation: Median N

Question 3

Flexor carpi ulnaris

Answer 3

Origin: Medial epicondyle of humerus, olecranon
Insertion: Pisiform, hook of Hamate
Action: Flex wrist, ulnar deviation
Innervation: Ulnar N

Question 4

Palmaris Longus

Answer 4

Origin: Medial epicondyle of humerus
Insertion: Palmar aponeurosis
Action: Flex wrist, (tighten palmar aponeurosis), (flex elbow)
Innervation: Median N

Question 5

Pronator Teres

Answer 5

Origin: Medial epicondyle humerus, coronoid process of ulna
Insertion: lat. surface radius
Action: Pronate RU joint, (flex elbow)
Innervation: Median N

Question 6

Flexor Digitorum Profundus

Answer 6

Origin: prox. anterior ulna, IO membrane
Insertion: Distal phalanges 2-5
Action: Flex wrist, Flex MCP, PIP, and DIP 2-5
Innervation: Anterior Interosseous N for digits 2-3, Ulnar N for digits 4-5

Question 7

Flexor Pollicis Longus

Answer 7

Origin: anterior radius, IO membrane
Insertion: Distal 1st phalanx
Action: flex wrist, flex 1st CMC, MCP, IP, (oppose CMC)(radially deviate wrist)
Innervation: Anterior Interosseous N

Question 8

Pronator Quadratus

Answer 8

Origin: Distal anterior surface of ulna
Insertion: Distal anterior surface radius
Action: Pronate RU
Innervation: Anterior interosseous N

Question 9

Brachioradialis

Answer 9

Origin: Lateral supracondylar ridge of humerus
Insertion: Styloid process of radius
Action: Supinate/pronate RU joint, flex elbow
Innervation: Radial N

Question 10

Extensor carpi radialis longus

Answer 10

Origin: Lateral supracondylar ridge of humerus
Insertion: Base of 2nd MC
Action: extend wrist, radially deviate, (flex elbow)
Innervation: Deep radial N

Question 11

Extensor carpi radialis brevis

Answer 11

Origin: Lateral epicondyle humerus
Insertion: Base of 3rd MC
Action: Extend wrist, radially deviate wrist, (flex elbow)
Innervation: Deep radial N

Question 12

Supinator

Answer 12

Origin: Supinator crest, Lateral epicondyle humerus
Insertion: lateral radius
Action: Supinate RU joint
Innervation: Deep radial N

Question 13

Extensor Digitorum (communis)

Answer 13

Origin: Lateral epicondyle humerus
Insertion: middle and distal phalanges 2-5
Action: Extend wrist, ext. MCP, PIP, DIP 2-5, (abd digits 2-5)
Innervation: Post. Interosseous N

Question 14

Extensor Digiti Minimi

Answer 14

Origin: Lateral epicondyle humerus
Insertion: 5th middle and distal phalanx
Action: (extend and ulnarly deviate wrist), Ext 5th MCP, PIP, and DIP (abd 5th)
Innervation: Post. Interosseous N

Question 15

Extensor carpi ulnaris

Answer 15

Origin: Lateral epicondyle humerus and post. ulna
Insertion: Base of 5th MC
Action: Extend and ulnarly deviate wrist
Innervation: Post. Interosseous N

Question 16

Abductor Pollicis Longus

Answer 16

Origin: Posterior ulna, posterior radius, IO membrane
Insertion: Base of 1st MC
Action: Abd 1st CMC (radially deviate wr)
Innervation: Post. Interosseous N

Question 17

Extensor pollicis brevis

Answer 17

Origin: Post. radius and IO membrane
Insertion: Base of 1st proximal phalanx
Action: Extend 1st CMC, MCP, (ext, radially deviate wr)
Innervation: Post. Interosseous N

Question 18

Extensor pollicis longus

Answer 18

Origin: Post. ulna and IO membrane
Insertion: Base of 1st distal phalanx
Action: Extend 1st CMC, MCP, IP, (add. 1st CMC)(extend and radially deviate wr)
Innervation: Post. Interosseous N

Question 19

Extensor Indicis

Answer 19

Origin: Post. ulna and IO membrane
Insertion: 2nd middle and distal phalanges
Action: Extend 2nd MCP, PIP, DIP, ext. wrist
Innervation: Post. Interosseous N