7N6 THE VASCULAR SYSTEMS 



with the long thoracic artery. The afferents of this group drain the skin and 

 muscles of the pectoral and subaxillary regions of the thorax and part of the 

 mammary gland; their efferents pass to the central and subdavicular nodes. 



(3) A posterior group, the subscapular chain, lying along the subscapular artery. 

 Their afferents drain the skin and muscles of the lower part of the neck and of the 

 posterior thoracic wall; their efferents pass to the central axillary group of nodes. 



(4) A central or intermediate group of three or four large nodes situated in the adi- 

 pose tissue near the base of the axilla, their afferents draining all the preceding 

 groups of axillary nodes; their efferent vessels end in the subdavicular nodes. 

 The nodes of the central group in many individuals protrude through the opening 

 in the axillary fascia known as the foramen of Langer. (5) A subdavicular group, 

 situated behind the upper margin of the Pectoralis minor. From the axillary 

 nodes come many vessels which, by anastomosing, form the infraclavicular plexus; 

 they then unite into a trunk, the subclavian trunk (truncus subclavius), which 

 courses between the subclavian vein and Subclavius muscle. On the right side 

 it empties into the junction of the internal jugular and subclavian vein or unites 

 with the jugular trunk to form the right lymphatic duct. On the left side it may 

 empty into the venous junction or into the thoracic duct. 



SUPRA- 

 CLAVICULAR 



LINE OFTHE 

 CLAVICLE 



SUBCLAVICULAR 



HUMERAL 



SCAPULAR 

 CHAIN 



PECTORAL GROUP 



FIG. 563. Scheme of the axillary nodes. The dotted line indicates the position of the clavicle. 



(Poirier and Charpy.) 



The Lymphatic Vessels of the Upper Extremity (Figs. 561, 504). 



The lymphatic vessels of the upper extremity are divided into the superficial 

 and the deep. 



The superficial lymphatic vessels of the upper extremity begin as plexuses 

 in the skin and form vessels which ascend in the subcutaneous tissue. These 

 plexuses are particularly plentiful in the palm and palmar surface of the digits 

 (Fig. 564). On each side of each finger two lymph vessels are formed; they 

 ascend toward the hand, cross the dorsum, and anastomose frequently with each 

 other. The vessels from the dorsum of the hand join the lymph vessels of the 

 forearm, which ascend chiefly along the superficial veins. The lymph vessels 

 which ascend with the superficial ulnar vein pass into the supratrochlear node. 

 The vessels which accompany the median veins pass into the antecubital or 

 supratrochlear nodes. Some of the lymph vessels on the radial side of the fore- 

 arm run up along the cephalic vein and terminate in the infraclavicular nodes. 

 All the other lymph vessels of the upper extremity pass direct to the axillary 



