Axilla

Question 1

Where is the axilla?

Answer 1

Inferior to the glenohumeral joint and superior to the skin and axillary fascia at the junction of the arm and thorax

Question 2

Which are the main parts that compose the axilla?

Answer 2

Apex, base, and 4 walls (3 are muscular)

Question 3

How is the apex of the axilla bounded?

Answer 3

Is the cervico-axillary canal (passageway between neck and axilla).
Bounded by: 1st rib, clavicle, and superior edge of the scapula

Question 4

How is the base of the axilla formed?

Answer 4

By concave skin, subcutaneous tissue, and axillary (deep) fascia extending from the arm to the thoracic wall (form the axillary fossa)

Question 5

How is the anterior wall of axilla formed?

Answer 5

By pectoralis major and minor and the pectoral and clavipectoral fascia associated with them
- “Anterior axillary fold” is the inferiormost part of the anterior wall

Question 6

How is the posterior wall of axilla formed?

Answer 6

Chiefly by the scapula and scapularis on anterior surface and inferiorly by teres major and latissimus dorsi
- “Posterior axillary fold” is the inferiormost part of the posterior wall

Question 7

How is the medial wall of the axilla formed?

Answer 7

By thoracic wall and the overlying serratus anterior

Question 8

How is the lateral wall of the axilla formed?

Answer 8

Narrow bony wall formed by intertubular sulcus of the humerus

Question 9

What is the course of the axillary artery?

Answer 9

1. Begins at lateral border of 1º rib as continuation of subclavian
2. Passes posterior to pectoralis minor into arm
3. Becomes brachial artery when passes distal to inferior border of teres major
4. Ends at inferior border of teres major

Question 10

Where is the 1º part of the axillary artery located?

Answer 10

Betweem lateral border of 1º rib and medial border of pectoralis minor; enclosed in axillary sheath

Question 11

Name the branch(or branches) of the 1º part of the axillary artery

Answer 11

Only 1 - superior thoracic artery

Question 12

Where is the 2º part of the axillary artery located?

Answer 12

Lies posterior to pectoralis minor

Question 13

Name the branch(or branches) of the 2º part of the axillary artery

Answer 13

2 branches - thoraco-acromial artery and lateral thoracic artery

Question 14

Where is the 3º part of the axillary artery located?

Answer 14

Extends from lateral border of pectoralis minor - inferior border of teres major

Question 15

Name the branch(or branches) of the 3º part of the axillary artery

Answer 15

3 branches - subscapular, anterior/posterior circumflex humeral artery (opposite to origin of subscapular)

Question 16

Describe the course of the axillary vein

Answer 16

1. Lies initially (distally) on the anteromedial side of the axillary artery, with its terminal part antero-inferior to the artery