Axilla II: Brachial Plexus

Question 1

what does the brachial plexus consist of?

Answer 1

5 VPR roots –> 3 trunks –> 6 divisions
–> 3 cords –> 5 terminal branches

Question 2

what do each of the 3 cords separate into?

Answer 2

1. Posterior cord → Axillary nerve, Radial nerve
2. Lateral cord → Musculocutaneous nerve, Lateral root of median nerve
3. Medial cord → Medial root of median nerve, Ulnar nerve

Question 3

what is the location, innervation, and sensory of the Musculocutaneous nerve?

Answer 3

• Location: Passes through Coracobrachialis muscle
  -Innervation: muscles of anterior compartment of brachium
  -Sensory: to lateral forearm

Question 4

what is the location, innervation, and sensory of the Axillary nerve?

Answer 4

-Location: quadrangular space
-Innervation: deltoid, teres minor
-sensory: shoulder over deltoid muscle

Question 5

what is the location, innervation, and sensory of the Radial nerve?

Answer 5

-Location: triangular interval
-innervation: Posterior compartment of brachium (triceps), antebrachium, and hand
-sensory: posterior of upper limb

Question 6

what is the location of the Median and Ulnar nerve?

Answer 6

forearm and hand

Question 7

what are the supraclavicular branches? where are they?

Answer 7

~above clavicle~
-Long thoracic
-Dorsal scapular
-Suprascapular
-Subclavius

Question 8

where does the long thoracic nerve branch from?

Answer 8

VPR C5-C7

Question 9

where does the dorsal scapular nerve branch from?

Answer 9

VPR C3-5

Question 10

what does the dorsal scapular nerve innervate?

Answer 10

Levator scapulae and Rhomboid major/minor

Question 11

what does the suprascapular nerve branch from?

Answer 11

superior trunk

Question 12

what does the suprascapular nerve innervate?

Answer 12

Supraspinatus, infraspinatus

Question 13

are the supraclavicular branches sensory or motor?

Answer 13

motor

Question 14

what are the infraclavicular branches? (7)

Answer 14

1. Lateral Pectoral nerve
2. Lower Subscapular nerve
3. Upper subscapular nerve
4. Thoracodorsal nerve
5. Medial Pectoral nerve
6. Medial antebrachial nerve
7. `Medial brachial cutaneous nerve

Question 15

which infraclavicular nerve(s) arise from the lateral cord?

Answer 15

lateral pectoral nerve

Question 16

what does the lateral pectoral nerve innervate?

Answer 16

pec major

Question 17

which nerves arise from the posterior cord in the infraclavicular branches?

Answer 17

-Lower Subscapular nerve
-Upper subscapular nerve
-Thoracodorsal nerve

Question 18

what does the Lower Subscapular nerve innervate?

Answer 18

subscapularis and teres major

Question 19

what does the Upper subscapular nerve innervate?

Answer 19

subscapularis

Question 20

what does the thoracodorsal nerve innervate?

Answer 20

latissimus dorsi

Question 21

what nerves arise from the medial cord in the infraclavicular branches?

Answer 21

-Medial Pectoral nerve
-Medial antebrachial nerve
-Medial brachial cutaneous nerve

Question 22

what does the medial pectoral nerve innervate?

Answer 22

pectoralis major and pectoralis minor

Question 23

what does the medial antebrachial nerve innervate?

Answer 23

medial antebrachium (forearm)

Question 24

what does the Medial brachial cutaneous nerve innervate?

Answer 24

medial of brachium

Question 25

the medial pectoral nerve is always ______ to the other medial nerves

Answer 25

proximal

Question 26

________ always branches off posterior cord before the thoracodorsal

Answer 26

upper subscapular nerve