Posterior Forearm Outcomes

Question 1

P, D, A, I Abductor pollicis longus

Answer 1

P: proximal post. radius, ulna & interosseous membrane
D: base of 1st metacarpal & trapezium
A: abducts & extends thumb @ carpometacarpal joint and radial deviation (C6-8)

Question 2

P, D, A, I Extensor carpi radialis brevis

Answer 2

P: lateral epicondyle of humerus
D: base of 3rd metacarpal
A: extends hand at wrist & radial deviation
I: radial n. (C6-8)

Question 3

P, D, A, I Extensor carpi radialis longus

Answer 3

P: lateral supracondylar ridge of humerus
D: base of 2nd metacarpal
A: extends hand @ wrist, radial deviation, assists in elbow flexion
I: radial . (C6-8)

Question 4

P, D, A, I Extensor carpi ulnaris

Answer 4

P: lateral epicondyle of humerus
D: base of 5th metacarpal
A: extends hand @ wrist & ulnar deviation
I: radial n. (C6-8)

Question 5

P, D, A, I Extensor digitorum

Answer 5

P: lateral epicondyle of humerus
D: extenosr expansions of digits 2-5
A: extends phalanges (primary-metacarpophalangeal & secondary-interphalangeal) & hand @wrist
I: radial n. (C6-8)

Question 6

P, D, A, I Extensor digiti minimi

Answer 6

P: lateral epicondyle of humerus
D: digital expansion 5th digit
A: extends 5th digit primary and secondary
I: radial n. (C7-8)

Question 7

P, D, A, I Extensor indicis

Answer 7

P: posterior surface of ulna & interosseous membrane
D: digital expansion of 2nd digit
A: extends 2nd digit primary and secondary
I: radial n. (C7-8)

Question 8

P, D, A, I Extensor pollicis brevis

Answer 8

P: posterior radial surface & interosseous membrane
D: base of 1st procimal phalanx
A: extends thumb (primary) and extends & adducts CMC joint
I: radial n. (C6-8)

Question 9

P, D, A, I Extensor pollicis longus

Answer 9

P: middle 1/3rd of posterior surface of ulna & interosseous membrane
D: base of 1st distal phalanx
A: extends thumb (CMC, primary, & secondary) (C6-8)

Question 10

P, D, A, I Supinator

Answer 10

P: lateral epicondyle of humerus, radial collateral lig & supinator crest of ulna
D: lateral surface of proximal radius
A: supinates forearm
I: radial n. (C5-6)

Question 11

How many layers does the posterior compartment have?

Answer 11

2: Superficial & Deep

Question 12

Describe the contents, actions, and neurovascular of the superficial layer of the posterior compartment of forearm?

Answer 12

Muscles: Brachioradialis, extensor carpi radialis longus & brevis, extensor digitorum, extensor digiti minimi, extensor carpi ulnaris
Actions: extensior of wrist & hand
I: radial n.
Arterial supply: radial & post interosseous aa.

Question 13

Describe the contents, actions, and neurovascular of the deep layer of the posterior compartment of the forearm?

Answer 13

Mm: Supinator, extensor indicis, Abductor pollicis longus, extensor pollicis brevis, extensor pollicis longus*
*outcropping thumb muscles
Actions: extend wrist and hand
I: radial n.
Arterial supply: radial & post interosseous aa.