L9_The Axilla (1) Flashcards
What are the borders of the axilla?
- superior: clavicle, scapula and 1st rib
- inferior (base): axillary skin, fascia at the lower border of the pectoralis major and teres major/latissimus dorsi
- anterior: pectoralis major and minor muscles
- posterior: subscapularis muscle, teres major and latissimus dorsi
- medial: serratus anterior
- lateral: humerus (intertubercular groove)
Contents of the axilla (3 main)
1- Axillary Sheath Containing: axillary artery, vein, brachial plexus ->main vessels that are going to supply the upper limb with blood or drain venous blood from the upper limb and also to provide motor and some cutaneous innervation to the upper limb. 2- Axillary Lymph Nodes (part of the lymphatic system) 3- Tendons of Biceps brachii and Coracobrachialis
Tell me the trajectory of the vasculature of the upper extremity (arteries)
1- subclavian artery transitions into axillary artery
2-Axillary artery has 3 parts (superior thoracic artery, lateral thoracic artery, subscapular artery) can be found by locating pectoralis minor
3- axillary artery transitions into the Brachial artery
4- the Brachial artery splits into 2 arteries (Ulnar artery and Radial artery)
What are the branches of the Subclavian Artery
VITC & D
V: vertebral artery
I: Internal artery
T: Thyrocervical Trunk
C: Costocervical Trunk (the superior intercostal artery originates from here and will divide into the posterior intercostal artery to do an anastamosis with the 1st and 2nd anterior intercostal artery)
& sometimes
D: Dorsal Scapular artery (sometimes it’s a branch from the sublcavian artery but sometimes it’a branch from the thyrocervical trunk
What are the branches of the Axillary artery?
First part(1) ->just superior to the superior border of the pectoralis minor muscle : Superior thoracic artery
Second part(2) -> deep to the pectoralis minor muscle: Thoracoacromial Trunk
- Clavicular (c)
- Acromial (A)
- Deltoid (D)
- Pectoral (P)
Lateral Thoracic artery
Third part(3) -> inferior surface of the pectoralis inferior minos muscle: Subscapular artery
- Circumflex scapular artery
- Thoracodorsal artery
Anterior and Posterior Humeral Circumflex arteries (they go around the humerus)
What passes through the quadrangular space?
- posterior humeral circumflex artery
What passes through the triangular space?
- Circumflex scapular artery
The dorsal scapular artery gives blodd innervation to which muscles?
- levator scapulae
- Rhomboid major and minor
The suprascapular artery gives blood innervation to which muscles?
- supraspinatus muscle
- infraspinatus muscle
The Thoracodorsal artery gives motor innervation to which muscle?
- Latissimus dorsi
The Circumflex Scapular artery gives blood innervation to which muscles?
- Infraspinatus
- Teres minor
Explain the superficial venous drainage of the upper limb
Anterior:
- The blood from the basilic vein can either travel along the median cubital vein or continue into the axillary vein
- The blood from the cephalic vein can also decide to travel along the median cubital vein or continue with the cephalic vien into the deltopectoral groove
Posterior:
- On the posterior side, the basilic vein and the cephalic vein merge together by the dorsal venous arch (DVA) on the dorsum of the hand
Tell me the trajectory of the Axillary vein
1- Paires brachial veins merge into the Basilic vein
2- The posterior humeral circumflex vein merge into the Basilic vein
3- The Cephalic vein (needs to peirce through the fascia) merge into the axillary vein
4- The basilic vein merge into the axillary vein
5- The axillary vein merge into the the subclavian vein
…
Tell me the functions of valves in the veins
- Valves in veins prevent backflow of venous blood due to gravity or internal pressure.
- When skeletal muscles contracts it shortens in length but increases in girth
Whats the functions of the lymphatic system?
- Removal of interstitial fluids
- Transports white blood cells
- Large role in immune system
What’s the name of the axillary lymph nodes?
(A) Apical nodes
(C) Central nodes
(H) Humeral Nodes
(S) Subscapular Nodes
(P) Pectoral Nodes
