Posterior

Question 1

Brachioradialis

Answer 1

O- Lateral supracondylar ridge of humerus; lateral intermuscular septum of arm
I- Lateral side of distal end of radius
A- Flexion of forearm
Inn- Radial Nerve (C5, C6)

Question 2

Extensor carpi radialis longus

Answer 2

O- Lateral supracondylar ridge and lateral intermuscular septum; epicondyle of humerus (common extensor tendon)
I- Base of second metacarpal
A- Extension and abduction (radial deviation) of hand
Inn- Radial nerve (C6, C7)

Question 3

Extensor carpi radialis brevis

Answer 3

O- Lateral epicondyle of humerus (common extensor tendon); intermuscular septa; antebrachial fascia
I- Base of third metacarpal
A- Extension of hand
Inn- Radial nerve (C6, C7)

Question 4

Extensor digiti minimi

Answer 4

O- Lateral epicondyle of humerus (common extensor tendon) and intermuscular septa in common with the extensor digitorum
I- Middle and distal phalanges of little finger
A- Extension and abduction of little finger
Inn- Radial nerve (C6-C8)

Question 5

Extensor digitorum

Answer 5

O- Lateral epicondyle of humerus (common extensor tendon); intermuscular septa; antebrachial fascia
I- Middle and distal phalanges of each of four fingers (medial four digits)
A- Extension of MCP joints of each four fingers (medial four digits)
Inn- Radial nerve (C6-C8)

Question 6

Extensor carpi ulnaris

Answer 6

O- Lateral epicondyle of humerus (common extensor tendon); proximal half of posterior border of ulna
I- Base of fifth metacarpal
A- Extension and adduction (ulnar deviation) of hand
Inn- Radial nerve (C7,C8)

Question 7

Supinator

Answer 7

O- Posterolateral surface of ulna below radial notch; lateral epicondyle; radial collateral and annular ligaments
I- Lateral and adjacent posterior and anterior aspects of proximal shaft of radius
A- supination of forearm (and hand)
Inn- Radial nerve (C5,C6)

Question 8

Abductor pollicis longus

Answer 8

O- Posterior surface of ulna and radius; interosseous membrane
I- Base of first metacarpal
A- Abduction and extension of thumb; abduction and flexion of hand at wrist
Inn- Radial nerve (C6-C8)

Question 9

Extensor pollicis brevis

Answer 9

O- Posterior surface of radius; interosseous membrane
I- Proximal phalanx of thumb
A- Extension of proximal phalanx and metacarpal of thumb; abduction of hand at wrist
Inn- Radial nerve (C7,C8)

Question 10

Extensor pollicic longus

Answer 10

O- Posterior surface of middle third of ulna; interosseous membrane
I- Distal phalanx of thumb
A- Extension of proximal and distal phalanges of thumb; extension and adduction of metacarpal of thumb
Inn- Radial nerve (C7,C8)

Question 11

Extensor indicis

Answer 11

O- Posterior surface of ulna; interosseous membrane
I- Extensor expansion of index finger
A- Extension and adduction of index finger
Inn- Radial nerve (C7,C8)