A&P 1.11

Question 1

Lateral Arm Muscles - L, O, I, A

Deltoid

Answer 1

L: Lateral shoulder superficial
O: - Anterior: Lateral 1/3 of clavicle
- Middle: Acromion
- Posterior: Spine of scapula
- I: Deltoid tuberosity of humerus
- A: - Anterior: Flexion, medial rotation
- Mid: ABduction
- Posterior: Extension & lateral rotation of arm at shoulder

Question 2

Deep Posterior/Lateral Forearm Muscles - L, O, I, A

Supinator

Answer 2

L: Posterior, lateral forearm deep
O: Lateral epicondyle of humerus & posterior border of ulna
I: Proximal 1/3 of radius
A: Supination of forearm at elbow

Question 3

Superficial Posterior Forearm Muscles - L, O, I, A

Extensor Carpi Radialis Brevis

Answer 3

L: Posterior forearm superficial
O: Kateral epicondyle of humerus
I: Base of 3rd metacarpal
A: Extension & radial deviation of hand at wrist

Question 4

Deep Posterior Forearm Muscles - L, O, I, A

Extensor Indicis

Answer 4

L: Posterior forearm deep
O: Ulna & interosseous membrane
I: Base of intermediate phalanx of index finger
A: Extension of index finger

Question 5

Deep Posterior Forearm Muscles - L, O, I, A

Extensor Pollicis Brevis

Answer 5

L: Posterior forearm deep
O: Radius & interosseous membrane
I: Base of proximal phalanx of thumb
A: Extension of thumb

Part of anatomical snuff box

Question 6

Deep Posterior Forearm Muscles - L, O, I, A

Extensor Pollicis Longus

Answer 6

L: Posterior forearm deep
O: Middle 1/3 of ulna & interosseous membrane
I: Base of distal phalanx of thumb
A: Extension of thumb

Part of anatomical snuff box

Question 7

Deep Posterior Forearm Muscles - L, O, I, A

Abductor Pollicis Longus

Answer 7

L: Posterior forearm deep
O: Ulna, radius & interosseous membrane
I: Base of 1st metacarpal
A: Abduction & extension of thumb

Part of anatomical snuff box

Question 8

Superficial Posterior Forearm Muscles - L, O, I, A

Extensor Digitorum

Answer 8

L: Posterior forearm superficial
O: Lateral epicondyle of humerus
I: Distal phalanges of medial 4 digits
A: Extension of phalanges

Question 9

Superficial Posterior Forearm Muscles - L, O, I, A

Extensor Carpi Ulnaris

Answer 9

L: Posterior forearm superficial
O: Lateral epicondyle of humerus
I: Base of 5th metacarpal
A: Extension & ulnar deviation of hand at wrist

Question 10

Superficial Posterior Forearm Muscles - L, O, I, A

Extensor Retinaculum (not a muscle)

Answer 10

L: CT band around posterior wrist
O: Attaches at distal radius & ulna
I: n/a
A: Keeps extensor tendons from bowing out

Question 11

Superficial Posterior Forearm Muscles - L, O, I, A

Anconeus

Answer 11

L: Posterior forearm superficial
O: Lateral epicondyle of humerus
I: Olecranon process & lateral edge of ulna shaft
A: Extends elbow (ABducts ulna during supination)