Dorsal Forearm

Question 1

• muscle originate from lateral epicondyle and epicondyle ridge of humerus
• extensors and supinators
• radial nerve innervates

Answer 1

posterior compartment of forearm

Question 2

• origin: supraepicondylar ridge
• insertion: lateral surface of radius
• flexes elbow joint when drinking (Popeye muscle)

Answer 2

brachioradialis

Question 3

• origin: lateral supraepicondylar ridge
• insertion: base of 2nd metacarpal
• extends and abduct/radially deviate wrist, steady wrist when clenching fist

Answer 3

extensor carpi radialis longus

Question 4

• origin: lateral epicondylar ridge
• inserts: base of 3rd metacarpal
• extends and abduct/radially deviate wrist, steady wrist when clenching fist

Answer 4

extensor carpi radialis brevis

Question 5

• origin: posterior surface of ulna, radius, interosseus membrnae
• inserts: base of 1st metacarpal
• abducts thumb

Answer 5

adbuctor pollicis longus

Question 6

• origin: posterior radius, interosseus membrane
• insertion: inserts on base of proximal phalanx of thumb
• extends thumb, forms lateral (palm side) border of anatomical snuffbox

Answer 6

extensor pollicis brevis

Question 7

• origin: posterior radius, interosseus membrane
• inserts: base of distal phalanx
• extends thumb
• forms medial/dorsal side of anatomical snuffbox

Answer 7

extensor pollicis longus

Question 8

Anatomical snuffbox is boarded by?

Answer 8

extensor pollicis longus (dorsally) and extensor pollicis brevis (palmar)

Question 9

What artery lies of floor of anatomical snuffbox?

Answer 9

radial

Question 10

What can be palpated in the floor of anatomical snuffbox?

Answer 10

scaphoid, trapezium, 1st metacarpal joint

Question 11

• origin: lateral epicondyle
• insertion: extensor expansion
• principal extensor of medial four digits
• tendons enter hand through common synovial sheath deep to extensor retinaculum
• intertendinous connection

Answer 11

extensor digitorum

Question 12

• origin: lateral epicondyle
• inserts onto extensor expansion of 5th digit
• extends 5th digit

Answer 12

extensor digit minimi

Question 13

• origin: lateral epicondyle
• inserts: base of 5th metacarpal
• most medial (ulnar)
• extends and adducts wrist, steadies wrist when clenching fist

Answer 13

extensor carpi ulnaris

Question 14

• origin: ulna, interosseus membrane
• inserts: 2nd extensor expansion
• extends index finger

Answer 14

extensor indicis

Question 15

• origin: lateral epicondyle
• inserts: lateral, ant/post surface of radius
• supinates forearm by rotating radius

Answer 15

supinator

Question 16

• repetitive forceful flexion and extension of wrsit (backhand in tennis, tree cutting, painting, butchers)
• inflammation of periosteum of lateral epicondyle
• pain at lateral epicondyle and radiates down posterior forearm
• pain when open door or lift glass

Answer 16

elbow tendinits (lateral epicondylitis)

Question 17

• unknown cause
• mucinous fluid, may communicate with synovial sheaths
• may cause median nerve compression

Answer 17

synovial cyst of the wrist

Question 18

-supplies skin of dorsal radial side of hand

Answer 18

superficial branch of radial nerve

Question 19

branch from radial nerve above elbow, supplies posterior forearm skin

Answer 19

posterior cutanoues nerve

Question 20

wrist drop

Answer 20

radial nerve injury