Brachial Plexus

Question 1

What forms the brachial plexus?

Answer 1

The union of the anterior rami of the last 4 cervical and first thoracic

Question 2

Where does the brachial plexus originate and where does it travel?

Answer 2

the neck and passes laterally and inferiorly over rib 1 and enters the axilla

Question 3

Where do the roots of the plexus pass through?

Answer 3

The gap between the anterior and middle scalene muscles

Question 4

What are the three trunks of the brachial plexus and how do they form?

Answer 4

Superior trunk - formed by the union of C5 and C6 roots
Middle trunk formed by a continuation of C7 root
Inferior trunk formed by the union of C8 and T1 ribs

Question 5

What is the order of sections in the brachial plexus?

Answer 5

Roots
Trunks 
Divisions
Cords 
Nerves

Question 6

What do the anterior divisions of the trunks supply?

Answer 6

The anterior (flexor) compartments of the upper limb

Question 7

What do the posterior divisions of the trunks supply?

Answer 7

Posterior compartments

Question 8

What are the three cords of the brachial plexus?

Answer 8

Lateral cord
Medial cord
Posterior cord

Question 9

What is the lateral cord?

Answer 9

A union of anterior divisions of upper and middle trunks

Question 10

What is the medial cord?

Answer 10

Continuation of anterior division of inferior trunk

Question 11

What is the posterior cord?

Answer 11

Union of all three posterior divisions

Question 12

What does the suprascapular nerve innervate?

Answer 12

Supraspinatus and infraspinatus

Question 13

What does the nerve to the subclavius muscle innervate?

Answer 13

Subcvlavius muscle

Question 14

What does the dorsal scapular nerve innervate?

Answer 14

Rhomboid major and minor muscles

Question 15

What does the long thoracic nerve innervate?

Answer 15

Serratus anterior muscle

Question 16

What does the musculocutaneous nerve innervate?

Answer 16

The anterior compartment
Coracobrachialis
Biceps brachii
Brachialis

Question 17

Where does the musculocutaneuos nerve innervate?

Answer 17

Lateral cutaneous nerve of foreman

Question 18

What forms the M over the third part of the axillary artery?

Answer 18

Musculocutaneuos nerve, lateral root of the median nerve,

medial root of the median nerve and ulnar nerve

Question 19

What are the 5 branches of the medial cord?

Answer 19

Medial pectoral nerve
Medial cutaneous nerve of arm 
medial cutaneous nerve of forearm
Ulnar nerve 
Median nerve

Question 20

What muscle does the medial pectoral nerve innervate?

Answer 20

Pectoralis major and minor

Question 21

What muscle does the medial cutaneous nerve of the arm innervate?

Answer 21

Medial 1/3 of distal arm

Question 22

What muscle does the medial cutaneous nerve of the forearm innervate?

Answer 22

Medial surface of the forearm down the wrist

Question 23

What are the five branches of the posterior cord?

Answer 23

Superior subscapular nerve
thoracodorsal nerve 
inferior subscapular nerve 
axillary nerve 
radial nerve

Question 24

What msucle does the superior subscapular nerve innervate?

Answer 24

Subscapularis muscle

Question 25

What muscle does the thoracodorsal nerve innervate?

Answer 25

Lattisimus dorsi

Question 26

What muscle does the inferior subscapular nerve innervate ?

Answer 26

Subscapularis and teres major

Question 27

What muscle does the axillaery nerve innervate?

Answer 27

Deltoid and teres minor

Question 28

What muscles are supplied by the median nerve?

Answer 28

Lateral two lumbricals
Opponens pollicis
Aductor pollicic brevis
Flexor pollicis brevis