Posterior compartment of the forearm

Question 1

What is the action of most of the muscles in the posterior compartment of the forearm

Answer 1

Extension

Question 2

What innervates all of the muscles in the posterior compartment of the forearm and where do most of there muscles originate

Answer 2

Innervated: Radial nerve

Origin for most is the lateral epicondyle of the humerus

Question 3

Name the 6 muscles of the of the superficial posterior forearm

Answer 3

1. Brachioradialis
2. Extensor Carpi Radialis Longus
3. Extensor Carpi Radialis Brevis
4. Extensor Carpi Ulnaris
5. Extensor Digiti Minimi
6. Extensor Digitorum

Question 4

What is the origin, insertion, action and innervation of Brachioradialis

Answer 4

Origin: Humerus

Insertion: radius

Action: supinate and protonate back to neutral aid in flexation of the elbow

Innervation: radial

Question 5

What is the origin, insertion, action and innervation of Extensor Carpi Radialis Longus

Answer 5

Origin: Distal humerus

Insertion: radial base of the posterior 2nd metacarpal

Action: extends wrist and radial deviation (along with flexor carpi radius)

Innervation: radial

Question 6

What is the origin, insertion, action and innervation of Extensor Carpi Radialis Brevis

Answer 6

Origin: lateral epicondyle of the humerus

Insertion: radial base of the posterior 3rd metacarpal

Action: extends wrist and radial deviation (along with extensor carpi longus and flexor carpi radius)

Innervation: radial nerve

Question 7

What is the origin, insertion, action and innervation of Extensor Carpi Ulnaris

Answer 7

Origin: lateral epicondyle of the humerus

Insertion: ulnar base of the posterior 5th metacarpal

Action: extends wrist and ulnar deviation (along with flexor carpi ulnaris)

Innervation: radial nerve

Question 8

What is the origin, insertion, action and innervation of Extensor Digiti Minimi

Answer 8

Origin: lateral epicondyle of the humerus

Insertion: phalanx of pinky (5th digit)

Action: extends 5th digit ( like Dr. Evil)

Innervation: radial nerve

Question 9

What is the origin, insertion, action and innervation of Extensor Digitorum

Answer 9

Origin: lateral epicondyle of the humerus

Insertion: phalanges 2-5

Action: extends phalanges 2-5

Innervation: radial nerve

Question 10

Name the 5 muscles of the of the deep posterior forearm

Answer 10

3 move the thumb, 1 move index finger (#2 finger), and 1 supinator

1. Abductor Pollicis Longus
2. Extensor Pollicis Longus
3. Extensor Pollicis Brevis
4. Extensor indicis
5. Supinator

Question 11

What is the origin, insertion, action and innervation of Abductor Pollicis Longus

Answer 11

Origin: Interosseous, posterior radius and ulna

Insertion: base of the thumb (1st metacarpal

Action: abducts the thumb

Innervation: radial nerve

Question 12

What is the origin, insertion, action and innervation of Extensor Pollicis Longus

Answer 12

Origin: posterior ulnar and interosseous

Insertion: distal phalanx of the thumb

Action: extends thumbs

Innervation: radial nerve

Question 13

What is the origin, insertion, action and innervation of Extensor Pollicis Brevis

Answer 13

Origin: posterior radius and interosseous

Insertion: proximal phalanx of the thumb

Action: extends the thumb

Innervation: radial nerve

Question 14

What is the origin, insertion, action and innervation of Extensor indicis

Answer 14

Origin: ulna and interosseous

Insertion: index finger

Action: extends the index finger

Innervation: radial nerve

Question 15

What is the origin, insertion, action and innervation of Supinator

Answer 15

Origin: lateral epicondyle of the radius and proximal ulna

Insertion: proximal radius

Action: supinates forearm

Innervation: radial nerve

Question 16

What arteries does the brachial artery split into after the cubital fossa

Answer 16

The radial and ulnar arteries

Question 17

What are the superficial veins of the forearm

Answer 17

the cephalic, basilic and median antebrachial