Axilla and Brachial Plexus Flashcards
What are the contents of the axilla?
- Axillary artery
- Scapular Anastomoses
- Axillary vein
- Axillary lymph nodes
- Cords and branches of the brachial plexus
What are the superior boundaries of the axilla?
- Cervicoaxillary canal
- 1st rib and clavicle
What are the inferior boundries of the axilla?
Axillary fascia
What are the medial boundaries of the axilla?
Upper ribs
-Serratus anterior
What is the lateral boundary of the axilla?
-intertubercular groove
What is the anterior boundary of the axilla?
- Attaches to the lateral lip
- Pectoralis Major
What is the posterior boundary of the axilla?
-Scapula
What are the branches of the axillary artery?
- Superior Thoracic Branch
- Thoracoacromial Branch
- Subscapular Branch
- Humeral Circumflex (posterior and anterior)
What branches/arteries come off of the Superior Thoracic Branch?
-Superior Thoracic Artery
What branches/arteries come off of the thoracoacromial branch?
DCPA
- Deltoid Artery
- Clavicular Artery
- Pectoral Artery
- Acromial Artery
- Lateral Thoracic Artery
What are the branches of Subscapular Trunk?
- Subscapular artery
- Thoracodorsal Artery
- Posterior Circumflex Artery
- Anterior Circumflex Artery
Where does the superior thoracic branch lie?
In the 1st and 2nd intercostal spaces
Where does the pectoral artery lie?
Under the pectoralis minor
Where does the thoracodorsal artery go?
It follows the thoracodorsal nerve and it goes to the Latissimus dorsi
What is the goal of the scapular anastomoses?
-Recurring pattern of redundant blood supply so if you have an injury to one artery- the blood still gets to the scapula
What are the 4 arteries that make up the scapular anastomose?
- suprascapular artery
- dorsal scapular artery
- posterior intercostalis artery
- circumflex scapular artery
What are the types of lymph nodes in the axilla?
- Humeral
- Pectoral
- Scapular
- Central
- Apical
What lymph nodes drain into the central lymph node?
- Humeral
- Pectoral
- Scapular
What lymph node drains into the apical lymph node?
Central (and all other previous contents)
Where does the apical lymph node drain into?
The venous angle to go back into circulation
Describe the brachial plexus
- Major nerve network of the upper extremity
- This expanded enlargements causes the cervical enlargement
- consists of anterior rami of spinal nerves
T/F- The roots of the brachial plexus are bidirectional?
True
What is the order of divisions of the brachial plexus?
- Roots
- Trucks
- Divisions
- Cords
- Branches
What are the roots that make up the brachial plexus?
C5-T1
What are the 3 trucks of the brachial plexus?
- Superior
- Middle
- Inferior
Where are the divisions located in the brachial plexus?
under the clavicle
Where do the anterior divisions innervate?
Anterior parts of the arm
Where do the posterior divisions innervate?
The posterior parts of the arm
What are the 3 cords?
Lateral
Posterior
Medial
What does the posterior cord turn into?
Divides into axillary and radial branches
What does the medial cord turn into?
Ulnar Nerve
What are 4 supraclavicaluar side branches?
- Dorsal Scapular
- Long Thoracic Nerve
- Suprascapular
- Nerve to Subclavius
What are the subclavicular side branches?
- Lateral Pectoral Nerve
- Upper subscapular
- Middle subscapular (thoracodorsal)
- Lower subscapular
- Medial Pectoral
- Medial cutaneous nerve of the arm
- Medial cutaneous nerve of the forearm
What branches come off the posterior cord?
- Upper subscapular
- Middle subscapular (thoracodorsal)
- Lower subscapular
What branches come off the medial cord?
- Medial Pectoral
- Medial cutaneous nerve of the arm
- Medial cutaneous nerve of the forearm
What happens in a upper brachial plexus injury?
- Caused- tearing or ripping or thrashing neck trauma
- Results in lack of abduction and external rotation
- Soooo symptoms would be that your arm is adducted and medially rotated slightly
What happens in a lower brachial plexus injury?
Klumpke Paralysis
- upper extremity is forcefully pulled away from the thorax
- C8 or T1
- Symptoms- claw hand (the 4th and 5th digits are extended and the other 3 are more fist like)
- Ulnar nerve paralysis