Axilla and neurovascular input to the upper arm

Question 1

What forms the anterior wall of the Axilla?

Answer 1

Pectoralis Major + Minor + Subclavius

Question 2

What forms the posterior wall of the axilla?

Answer 2

Latissmus Dorsi + Teres Major + Subscapularis

Question 3

What forms the medial wall of the axilla?

Answer 3

Thoracic wall + Serratus anterior

Question 4

What forms the lateral wall of the axilla?

Answer 4

Intertubercular groove of humerus

Question 5

What are the contents of the axilla?

Answer 5

• Axillary artery
• Axillary vein
• Axillary lymph nodes
• Brachial plexus
• Biceps Brachi (short head) and coracobrachialis

Question 6

At what anatomical point does the axillary artery begin?

Answer 6

Lateral margin of 1st rib

Question 7

At what anatomical point does the brachial artery begin?

Answer 7

Lower margin of teres major

Question 8

What nerve roots constitute the Brachial plexus?

Answer 8

C5-T1

Question 9

What nerve roots form the upper trunk of the brachial plexus?

Answer 9

C5-6

Question 10

What nerve roots form the middle trunk of the brachial plexus?

Answer 10

C7

Question 11

What nerve roots form the lower trunk of the brachial plexus?

Answer 11

C8-T1

Question 12

What is Erb’s point?

Answer 12

• Erb’s point is the convergance of C5+C6 when they form the upper trunk
• If damaged this can cause Erb’s palsy

Question 13

What is Erb’s palsy?

Answer 13

• Injury to the upper trunk of brachial plexus
• Results in “waiters tip” of upper limb
• Arm is medially rotated, wrist flexed

Question 14

What muscles are affected in Erb’s palsy

Answer 14

• Deltoid
• Wrist extensors
• Elbow flexors

Question 15

What can cause Erb’s palsy?

Answer 15

• Hyperextension of head form shoulder
• I.e Fall on shoulder, birth injury or iatrogenic

Question 16

What is Klumpke’s palsy?

Answer 16

• Injry to the lower trunk of the brachial plexus
• Affects intrinisc muscles of hand and ulnar flexors of wrist and fingers

Question 17

What causes klumpkes palsy?

Answer 17

Hyper abduction of the arm

Question 18

What are the cords of the brachial plexus?

Answer 18

Lateral Medial Posterior

Question 19

What are the branches of the lateral cord of the brachial plexus?

Answer 19

• Lateral pectoral nerve
• Median nerve (lateral root)
• Musculocutaneous nerve

Question 20

What are the branches of the medial cord of the brachial plexus?

Answer 20

• Medial pectoral nerve (C8-T1)
• Medial cutaneous nerve of arm (T1)
• Medial cutaneous nerve of forearm (C8-T1)
• Ulnar nerve

Question 21

What are the branches of the posterior cord of the brachial plexus?

Answer 21

• Thoracodorsal
• Axillary nerve
• Radial nerve
• Subscapular nerve

Question 22

What does the lateral pectoral nerve supply?

Answer 22

Pectoralis major

Question 23

What does the medial pectoral nerve supply?

Answer 23

Pectoralis muscles

Question 24

What does the thoracodorsal nerve suply?

Answer 24

Latissimus dorsi

Question 25

What does the subscapular nerve supply?

Answer 25

Teres major + Supsacpularis

Question 26

What is the sensory value + nerve of the badge area?

Answer 26

Axillary nerve - C5/6

Question 27

What are the different axillary lymph nodes?

Answer 27

• Pectoral group
• Subscapular group
• Apical group
• Central group
• Lateral group