AXILLARY SPACE 



A. thoracalis 

 suprema 



\from the first 

 / part. 



. Ifsecond 

 A. thoracalis lateralisl P artl 



A. subscapularis . 

 A. circumflexa 



humeri anterior 

 A. circumflexa 



humeri posterior ^ 



from the 

 third part. 



A. Thoracalis Suprema (O.T. Superior Thoracic). This is 

 a small branch which springs from the axillary at the 

 lower border of the subclavius. It ramifies upon the upper 

 part of the medial wall of the axilla and supplies twigs to 

 adjacent structures. 



A. Thoracoacromialis (O.T. Acromio-thoracic or Thoracic 

 Axis). The thoraco-acromial artery is a short, wide trunk, 

 which takes origin under cover of the pectoralis minor. It 

 winds round the upper border of that muscle, pierces the costo- 

 coracoid membrane, and immediately divides into numerous 

 branches, which diverge widely from each other. These re- 

 ceive different names, and are arranged as follows : (a) The 

 ramus clavicularis, a small twig, which runs up wards to the clavicle 

 and then turns medially along that bone between the clavicular 

 part of the pectoralis major and the costocoracoid membrane. 

 (ft) The rami perforates, of larger size, proceed downwards be- 

 tween the two pectoral muscles, give branches to both, and 

 they anastomose with the lateral thoracic and the lateral 

 branches of the intercostal arteries, (c] The ramus acromialis 

 runs laterally upon the tendon of the pectoralis minor and 

 the coracoid process. Some of its twigs supply the deltoid, 

 whilst others pierce it to reach the superior surface of the 

 acromion. It anastomoses with the transverse scapular 

 (suprascapular) and posterior circumflex humeral arteries. 

 (d) The ramus deltoideus, as a rule, takes origin from a 

 trunk common to it and the preceding artery. It runs 

 distally in the intermuscular interval between the pectoralis 

 major and the deltoid and supplies both muscles. 



A. Thoracalis lateralis (O.T. Long Thoracic). This vessel 

 takes the lower border of the pectoralis rm'nor as its guide, 

 and proceeds distally and medially to the side of the 

 thorax. It gives branches to the neighbouring muscles, and 

 it anastomoses with twigs from the intercostal arteries. It 

 also supplies the mamma, giving off, as a rule, an external 

 mammary branch, which winds round or pierces the lower 

 border of the pectoralis major on its way to the gland. 



Alar Thoracic. This small artery supplies the fat and lymph glands 



