Brachial Plexus And Axilla (2)

Question 0

What are the 3 parts of the axillary artery?

Answer 0

• Axillary sheath
• Posterior to pectoralis minor
• Pec minor to teres major.

Question 1

What are the contents of the axilla?

Answer 1

• Axillary artery
• Axillary vein
• Lymphatic vessels
• Axillary lymph nodes
• Axillary fat
• Brachial plexus

Question 2

What does the axillary sheath consist of?

Answer 2

• One branch: superior thoracic artery

Question 3

What does the posterior to pec minor consist of?

Answer 3

• 2 branches: - thoracocromial

- lateral thoracic arteries

Question 4

What does the pec minor to teres major consist of?

Answer 4

• 3 branches: - subscapular artery
  - anterior circumflex humeral
  - posterior circumflex humeral

Question 5

Outline the structure and role of the axillary vein.

Answer 5

• Lies on anteromedial side of axillary artery
• Union of basilic and brachial vein at inferior border of teres major
• Role: Collateral route for blood. Allows venous return in obstruction of IVC

Question 6

What is the teres major?

Answer 6

• Origin: dorsal surface of the inferior angle of the scapula
• Inserts: medial lip of the intertubercle sulcus of the humerous
• Action: medial rotator and aids adduction of humerous. Stabilises humeral head in the glenoid cavity.

Question 7

Where are the lymph nodes found in the axilla and what are the 5 different groups?

Answer 7

• Axillary fat
• Pectoral
• Subscapular
• Humeral
• Central
• Apical

Question 8

Which lymph nodes drain into the central nodes?

Answer 8

• Pectoral
• Subscapular
• Humeral

Question 9

Where are the central nodes situated?

Answer 9

• Deep to pectoralis minor

Question 10

Once drained into the central nodes what happens to lymph?

Answer 10

• Efferent vessels from central nodes travel to apical nodes
• Majority then drain into subclavian lymphatic trunk
• RHS - right lymphatic duct
• LHS - thoracic duct

Question 11

How is the brachial plexus split?

Answer 11

• Roots
• Trunks
• Divisions
• Cords
• Branches

Question 12

Which sections of the vertebral column give rise to the trunks and which sections supply which trunks?

Answer 12

• C5 & C6: Superior
• C7: Middle
• C8 & T1: Inferior

Question 13

What are the cords called and which one branches off to the axillary nerve?

Answer 13

(Superior to inferior)

• Lateral
• Proximal - axillary nerve
• Medial

Question 14

Name the terminal nerves from superior to inferior.

Answer 14

• Musculocutaneous
• Medial
• Radial
• Ulnar