OIAN 15

Question 1

Flexor pollicis longus

Answer 1

Origin:
- Middle of anterior radius and interosseous membrane (sometimes as high as the coronoid process of ulna)
Insertion:
- Palmar aspect of base of the distal phalanx of thumb
Action:
- Flexes the distal phalanx of thumb
- Helps flex the other joints to the wrist (McP, CMC)
Nerve:
- Median
- C8, T1

Question 2

Pronator quadratus

Answer 2

Origin:
- Distal ¼ anteromedial surface of ulna
Insertion:
- Distal ¼ anterolateral surface of radius
Action:
- Pronates the forearm 
Nerve:
- Median
- C8, T1

Question 3

Brachioradialis

Answer 3

Origin:
- Lateral supracondylar ridge of humerus
Insertion:
- Styloid process of radius
- Lateral side of distal 1/3 of radius
Action:
- Flexes the elbow (most when thumb up)
- Pronates the forearm when supinated
- Supinates the forearm when pronated
Nerve:
- Radial 
- C6,7,8

Question 4

Extensor carpi radialis longus

Answer 4

Origin:
- Lower lateral supracondylar ridge (below the brachioradialis)
Insertion:
- Base of 2nd metacarpal (dorsum)
Action:
- Extends the wrist
- Radially deviates the wrist
- Weakly flexes the elbow
- Weakly supinates the forearm
Nerve:
- Radial 
- C6,7,8

Question 5

Extensor carpi radialis brevis

Answer 5

Origin:
- Lateral epicondyle via the CET
Insertion:
- Base of 3rd metacarpal (dorsum)
Action:
- Extends the wrist
- Radially deviates the wrist
Nerve:
- Radial 
- C6,7,8

Question 6

Extensor carpi ulnaris

Answer 6

Origin:
- Lateral epicondyle via the CET
Insertion:
- Medial side of base of the 5th metacarpal
Action:
- Extends the wrist
- Ulnarly deviates the wrist
Nerve:
- Radial 
- C6,7,8