Axillary Artery PDF

Axilla Axillary Artery - Beginning (Fig. 59): it begins at the outer border of the first rib as the continuation of the subclavian artery. - Course and parts (Figs. 59, 60): It enters the axilla through its apex. Then it runs downwards and laterally along...

Axilla Axillary Artery - Beginning (Fig. 59): it begins at the outer border of the first rib as the continuation of the subclavian artery. - Course and parts (Figs. 59, 60): It enters the axilla through its apex. Then it runs downwards and laterally along the lateral wall of the axilla. The axillary artery passes deep to the pectoralis minor muscle which divides it into three parts: First part: above pectoralis minor. Second part: deep to pectoralis minor. Third part (the longest part): below pectoralis minor. - End: it ends at the lower border of the teres major muscle (lower limit of axilla) where it becomes the brachial artery. - Relations (Figs. 60, 61): : Relations of the First part: * Medially: axillary vein * Laterally: the lateral and posterior cords of brachial plexus. * Anteriorly: anterior-wall of axilla. * Posteriorly: Medial cord of brachial plexus and medial wall of axilla : Relations of the second part * Anteriorly: Pectoralis major and minor muscles. * Posteriorly: Posterior cord of brachial plexus Subscapularis muscle * Medially: Medial cord of brachial plexus A Axillary vein ML * Laterally: Lateral cord & B Coraco-brachialis muscle ⑭ s  Axilla ! Relations of the third part: it is partly superficial and its pulsations can be felt at the posterior fold of axilla. *Anteriorly: Medial root of median nerve crossing from medial to lateral. Pectoralis major muscle. N.B. Since the anterior wall of the axilla is slightly shorter than its posterior wall, the lowermost part of the axillary artery becomes superficial (only covered by skin and fascia) below the lower border ofpectoralis major. * Posteriorly: Radial and axillary nerves The posterior wall of axilla: subscapularis, teres major and latissimus dorsi (from above downwards). * Laterally. · Branches of lateral cord and median nerve. * Medially, branches of medial cord and axillary vein. :. common c;urotfd o. Rodml ModiCll ontcbrochiQI cutoneou1 n. Fig. 61: Relations of the axillary artery to bracxhial plexus (Ant. View)  Axilla Suoclavlus PectOtalls minOt ⑪ Superior thoracic artery ② Thoraco-acromial artery Subscapularis ③ Subscapular artery ③ Anterior circumflex humeral artery · · Posterior circumflex humeral artery (quadrangular Latissimus d o r s i - - - -- - - - + - + - Circumflex scapular branch - -1---4--..---'1-""""-':.1.' (triangular space) Teres major _ _ _ _ _ _ __,_ _-P-r. Thoracodorsal artery _ _ ③ Profunda brachil artel'{ Mangular intervarJ ② Fig. 59: Axillary artery course & branches Middl;e........+--·C4 Lower ,,. Metllal eord Pos.tenor cord--...,....-.............._ · Lateral oor(j T1 B Fig. 60: Relations of axillary artery  Axilla - Branches of the axillary artery (Fig. 59): ! First part, gives one branch: The superior thoracic artery: arises at the lower border of subclavius muscle to supply it and anastomoses with intercostal arteries. ! Second part gives two branches: 1. Acromio-thoracic artery: It is a short trunk arising behind the upper border of pectoralis minor. It pierces the clavi-pectoral fascia and ends by dividing into four branches: a. Acromial branch: runs towards the acromion b. Pectoral branch (the largest branch): descends between the two pectoral muscles supplying them and the breast. c. Clavicular branch: supplies subclavius muscle and sterno- clavicular joint. d. Deltoid branch: passes in the deltopectoral groove and supplies the deltoid and pectoralis major muscle. 2. Lateral thoracic artery: It arises behind the lower border of pectoralis minor and runs along this lower border to reach the side of the chest. It supplies the serratus anterior, the pectoral muscles and subscapularis. In females, it is large and gives lateral mammary branches supplying the lateral part of the gland. ! Third part: Gives three arteries: 1. Subscapular Artery (the largest branch): It arises at the lower border of subscapularis muscle where it gives a large branch called circumflex scapular artery. Below this branch the artery continues as thoraco-dorsal artery, it supplies latissimus muscle, and sharing in the anastomosis around the scapula. * The circumflex scapular artery: is usually larger than the continuation of the subscapular artery (the thoraco-dorsal artery). It curves around the lateral border of scapula traversing the upper triangular space. It shares in the anastomosis around the scapula. 2. Anterior circumflex humeral artery (a very small artery): arises at the lower border of subscapularis muscle. It runs in front of the surgical neck of humerus. It gives off an ascending branch to supply shoulder joint and ends by anastomosing with the posterior circumflex humeral artery.