axilla & brachial plexus

Question 1

Boundaries of the axilla

Answer 1

Anterior: Pectoralis major and minor
Posterior:scapula, latissimus dorsi, teres major
medial: ribs 1-4 and intercostal spaces
lateral intertubercular groove of the humerus
base: skin and fascia of arm
apex: convergence of clavicle, scapula and rib 1

Question 2

What are the contents of the axilla?

Answer 2

Axillary artery, axillary vein, brachial plexus, lymphatics

Question 3

Where does the axillary artery come from ?

Answer 3

The subclavian artery

Question 4

where does the axillary artery begin and end?

Answer 4

Lateral border of rib 1 and ends at the inferior border of the teres major

Question 5

Where is part 1 of the axillary artery?

Answer 5

Between the lateral border of 1st rib and medial border of the pectoralis minor

Question 6

Where is part 2 of the axillary artery?

Answer 6

Lies posterior to pectoralis minor

Question 7

Where is part 3 of the axillary artery?

Answer 7

From lateral border of the pectoralis minor to the inferior border of the teres major

Question 8

what are the branches off part 1 of the axillary artery?

Answer 8

superior thoracic artery

Question 9

what are the branches off part 2 of the axillary artery?

Answer 9

thoracoacromial trunk

lateral thoracic arteries

Question 10

what are the branches off part 3 of the axillary artery?

Answer 10

subscapular artery
anterior humeral circumflex
posterior humeral circumflex

Question 11

what joins to for the axillary vein?

Answer 11

The brachial veins and basilica vein

Question 12

Where does the axillary vein start?

Answer 12

at the inferior border of the teres major

Question 13

What are the 5 major groups of axillary lymph nodes?

Answer 13

• pectoral nodes
• subscapular node
• humeral node
• central group
• apical nodes

Question 14

Where do the pectoral nodes receive lymph?

Answer 14

mainly from the anterior thoracic wall including most of the breast

Question 15

Where do the subscapular nodes receive lymph?

Answer 15

posterior aspect of the thoracic wall and scapular region

Question 16

Where do the humeral nodes receive lymph?

Answer 16

nearly all lymph from upper limb

Question 17

Where do the central group of lymph nodes receive lymph?

Answer 17

from the pectoral, subscapular, and humeral nodes

Question 18

Where do the apical nodes receive lymph?

Answer 18

From the central nodes

Question 19

What forms the brachial plexus?

Answer 19

Ventral rami of spinal nerves C5-C8 and T1

Question 20

what info do the posterior roots transmit?

Answer 20

Sensory info

Question 21

what info do the anterior roots transmit?

Answer 21

Motor

Question 22

dermatome

Answer 22

innervating a segment of skin (think dermatology-skin)

Question 23

myotome

Answer 23

innervating specific muscles (think myocytes, muscle cells)

Question 24

what does dorsal rami innervate?

Answer 24

deep back muscles/skin

Question 25

what does ventral rami innervate?

Answer 25

Trunk/limbs

Question 26

Branching pattern of the brachial plexus

Answer 26

Roots
trunks
divisions
Cords 
Branches(terminal)