Flashcards in 1. The axilla Deck (8)
What is the axilla?
area that lies beneath the GH joint, at junction of upper limb and thorax
name the borders of the axilla.
- apex = cervico-axillary canal bounded by 1st rib, clavicle and superior edge of scapula
- posterior wall = subscapularis (overlying scapula), teres major and latissimus dorsi
- anterior wall = pec. major and minor
- medial wall = seratus anterior overlying thoracic wall
- lateral wall = intertubercular groove of humerus
describe the contents of the axilla
lateral to medial:
- tendons of biceps brachii and coracobrachialis
- brachial plexus (deep)
- axillary artery
- axillary vein
- axillary lymph nodes
what are the 3 main routes by which structures leave the axilla?
1- immediately inferiorly and laterally into upper limb - main route of exit
2- via quadrangular space - gap in posterior wall of axilla, allowing access to posterior arm and shoulder area (e.g. axillary n. and posterior circumflex humeral artery)
3- via clavipectoral triangle - opening into anterior wall of axilla (e.g. entrance of cephalic vein, exit of lateral pectoral nerves)
What are the 5 principal groups of axillary lymph nodes.
1. pectoral (anterior) nodes: 3-5 nodes along medial wall of axilla, around lateral thoracic vein and inferior borders of pectoralis minor
2. subscapular (posterior) nodes: 6-7 nodes along posterior axillary fold and subscapular blood vessels
3. humeral (lateral) nodes: 4-6 nodes along lateral wall of axilla, medial and posterior to axillary vein
4. central nodes: 3-4 large nodes deep to pectoralis minor, associated with 2nd part of axillary artery
5. apical nodes: at axilla apex
Describe the drainage of lymph by the axillary nodes.
1. pectoral nodes: receive lymph from anterior thoracic wall, inc. most of breast
2. subscapular nodes: receive lymph from posterior aspect of thoracic wall and scapular region
3. humeral nodes: receive nearly all lymph from upper arm
4. central nodes: receive lymph from pectoral, subscapular and humeral nodes
5. apical nodes: receive lymph from all other groups of axillary nodes as well as from lymphatics accompanying proximal cephalic vein
What happens to the efferent vessels from apical nodes?
traverse the cervicoaxillary canal and unite to form the subclavian lymphatic trunk