Brachial Plexus

Question 1

From proximal to distal, the brachial plexus consists of? (5)

Answer 1

1. Randy – Roots
2. Travis – Trunks
3. Drinks – Divisions
4. Cold – Cords
5. Beer – Branches

Question 2

How many roots and which ones?

Answer 2

1. 5 Roots

2. C5, C6, C7, C8,T1

Question 3

How many trunks? Names?

Answer 3

1. 3

2. Upper, middle and lower trunk

Question 4

How are trunks divided?

Answer 4

1. C5+C6 = Upper trunk
2. C7 = Middle trunk
3. C8+T1 = Lower trunk

Question 5

Which nerves come form the roots?(2)

Answer 5

1. Dorsal scapular N. (C4, C5)

2. Long thoracic N. (C5, C6, C7)

Question 6

Dorsal scapular N innervates what? Roots?

Answer 6

1. Rhomboid muscles and Levator scapulae

2. C4,C6,C5

Question 7

Long thoracic N innervates what? Roots?

Answer 7

1. Serratus anterior

2. C5, C6, C7

Question 8

How do the trunks divide to form divisions? Where?

Answer 8

1. Each trunk splits into Anterior and Posterior divisions 2.Just behind and above the clavicle.

Question 9

Which nerves come form the divisions?(2)

Answer 9

1. Nerve to the subclavius C5, C6

2. Suprascapular nerve C5, C6

Question 10

Nerve to the subclavius innervates what? Roots?

Answer 10

1. Subclavius muscle

2. C5,C6

Question 11

Suprascapular N innervates what? Roots?

Answer 11

1. Supraspinatus and Infraspinatus

2. C5, C6

Question 12

How do the divisions form the cords?

Answer 12

1. Anterior divisions of Upper and Middle trunks = Lateral cord (C5-C7)
2. Posterior divisions of All 3 trunks = Posterior cord (C5-T1)
3. Anterior division of Lower trunks = Medial cord (C8-T1)

Question 13

What does the Posterior cord turn in to? (5)

Answer 13

1. Axillary: C5, C6
2. Radial: C6, C7, C8, 1 T
3. Upper subscapular: C5, C6
4. Lower subscapular: C5, C6
5. Thoracodorsal: C5, C6, C7

Question 14

What is the lateral core formed form?

Answer 14

The anterior divisions of the upper (C5-C6) and middle trunks (C7).

Question 15

What does the lateral cord turn in to? (3)

Answer 15

1. Lateral pectoral nerve (C5, C6, C7)
2. Musculocutaneous nerve (C5, C6)
3. Median nerve (partial; C6, C7)

Question 16

Axillary N innervates what? Roots?

Answer 16

1. Deltoid and Teres minor

2. C5, C6

Question 17

Radial N innervates what?(12) Roots?

Answer 17

Triceps
Anconeus
Brachialis (lateral third)
Extensor carpi radialis longus

-Deep branch 
Supinator
Extensor carpi radialis brevis 
Extensor digitorum 
Extensor carpi ulnaris
Extensor pollicis longus 
Extensor pollicis brevis 
Extensor indicis 
Abductor pollicis longus

2.C6, C7, C8, 1 T