Axilla Flashcards
What makes up the apex of the axilla?
Apex: cervico-axillary canal
-bounded by 1st rib, clavicle and superior border of scapula.
What makes up the base of the axilla?
Base: formed by concave skin, subcutaneous tissue and axillary fascia extending from arm to thoracic wall.
- Forms axillary fossa (armpit)
- bounded by anterior and posterior axillary folds, thoracic wall and medal aspect of arm.
What makes up the anterior wall of axilla?
Anterior wall: formedby pectoralis major/minor mm. and deep fascias.
-anterior axial fold: inferior most part of anterior wall that can be grasped which is formed by pectoralis major m. and overlying skin.
What makes up the posterior wall of axilla?
Posterior wall: formed by scapula, subscapularis, trees major and latissimus dorsi mm.
-Posterior axial fold: inferior most part of posterior wall that may be grasped , extends further inferior than anterior wall, formed by latissimus corse and trees major mm. and skin.
What makes up the medial wall of axilla?
Medial wall: formed by thoracic wall.
-1st-4th ribs and intercostal mm. and serratus anterior m.
What makes up the lateral wall of axilla?
Lateral wall: formed by inter tubercular groove of humerus (narrow wall)
What does the axilla contain?
contains:
- axillary blood vessels
- lymphatic vessels and nodes
- axillary fat
- cords and branchesof brachial plexus
What is the axillary artery continuous with and what does it become?
Continuos with Subclavian a. and becomes brachial a.
In the 1st part of the axillary artery what is branches off in this section?
- From lateral border of 1st rib to medial border of pectoralis minor m.
- Superior (supreme) thoracic a.
What are the branches in the 2nd part of the axillary artery?
- Posterior to pectoralis minor
- Thoracoacromial trunk which was four branches-> clavicular, acormial deltoid, pectoral.
- Lateral thoracic a
What are the branches of the 3rd part of the axillary artery?
- From lateral border of pectoralis minor to inferior border of teres major
- subscapular a.
- anterior humeral circumflex a.
- posterior humeral circumflex a. ->found in quadrangular space.
Scapular anastomoses involves what arteries?
- Dorsal scapular a.
- Suprascapular a.
- Circumflex scapular a. (via subscapular a.)
What is the key player in scapular anastomosis?
Circumflex scapular a.
-it is via its anastomoses with supra scapular, dorsal scapular and even intrecostal aa. that allow bloode flow to be reversed through the sub scapular a. thus reaching the 3rd part of the axillary a.
The surgical ligation of the axillary a. between what two arteries will cut off blood supply to arm?
between subscapular a. and profunda brachii a.
The axillary vein is formed by the union of….. and it occurs where?
Brachial vv. (venae comitatnates) and basilic v.
-occurs at inferior border of trees major m.
The axillary vein ends at….. and becomes what?
Ends at lateral border of 1st rib and becomes subclavian v.
What does the axillary vein receive?
Cephalic v.
Where are the axillary lymph nodes (arranged in 5 groups)?
- Pectoral (anterior) nodes:lie along medal wall of axilla
- Subscapular (posterior) nodes: lie along posterior axillary fold
- Humeral (lateral) nodes: lie along lateral wall of axilla
- Central nodes: lie dep to pectoralis minor m.
- Apical nodes: located at apex of axilla
Where do pectoral, subscapular, humeral, central and apical nodes receive lymph?
- Pectoral receive lymph mainly from anterior thoracic wall and scapular region
- Subscapular receive lymph from posterior thoracic wall and scapular region.
- Humeral receives nearly all lymph from upper limb
- Central receive lymph from the above 3 groups
- Apical receives lymph from all groups of axillary nodes as well as those accompanying cephalic v.
Where does the brachial plexus begin and end?
Begins in neck and extends to axilla.
What forms the union of brachial plexus…. VPR of?
VPR of C5-C8 and T1
-often C4 and T2 will contribute
What do C5-C6 primarily innervate?
Primarily innervate mm. that act at shoulder or flex elbow.
What do C7-8 innervate?
innervate mm. that extend elbow or are part of forearm
What does T1 primarily innervate?
primarily innervates intrinsic mm. of hand
Where do almost all branches of the brachial plexus arise?
Almost all branches arise in axilla
Brachial Roots unite to form 3 trunks, what are they and what forms them?
- Superior trunk: formed by union of C5 and C6 (sometimes C4)
- Middle trunk: continuation of C7
- Inferior trunk: formed by union of C8 and T1 (sometimes T2)
Where are the following located:
- roots and trunks
- Divisions
- Cords and branches
- Roots and trunks: are in the neck
- Divisions: are deep to the clavicle
- Cords and branches: are in the axilla
