1010 THE VASCULAR SYSTEM. 



the elbow the vessels of the two streams anastomose together and some pass through the fascia 

 and join the deep cubital glands. 



As they pass from the forearm to the arm, the majority of the lymph vessels converge 

 towards the medial side. Some join the superficial cubital glands, but others pass those glands 

 and accompany their efferents, along the basilic vein, to the axilla where they join the lateral 

 group of axillary glands. There is, however, a varying number of lymph vessels, from the 

 lateral stream of the forearm, which accompany the cephalic vein in the arm. Some of these 

 terminate in the delto-pectoral gland, if it is present, but, whether it is present or not, some 

 pass directly to the infra-clavicular glands. 



The superficial lymph vessels of the arm terminate, for the most part, in the lateral group 

 of axillary glands. 



The deep lymph vessels of the upper extremity accompany the deeper blood-vessels. Some 

 of the lymph vessels of the hand and forearm end in the deep glands, which are occasionally 

 present in the forearm, but the majority either end in the deep cubital glands, or they pass 

 directly to the lateral group of axillary glands. 



The Lymph Vessels of the Mamma. As the mamma is a modified skin gland, 

 and as it is embedded in the superficial fascia, the lymph vessels which issue from it 

 pass first into the superficial fascia and thence into the deep fascia. Having traversed 

 the deep fascia, more or less obliquely, they either end in lymph glands or enter and 

 traverse other layers of the body wall. 



The main outflow of lymph from the substance of the mamma is towards the areola, 

 where a subcutaneous plexus of lymph vessels is formed. From that plexus two or more 

 main vessels of large size pass laterally (Fig. 806), pierce the deep fascia and join the anterior 

 group of axillary glands. There are, however, other groups of vessels by which lymph 

 may pass from the rnamma. Some vessels issue from the medial border of the gland and 

 run along the lines of the neighbouring anterior perforating branches of the internal 

 mammary artery to the anterior ends of the intercostal spaces ; there they pass 

 through the deeper parts of the thoracic wall and end in the sternal lymph glands. 

 Clinical evidence (Sampson Handley) has shown that some vessels, from the lower 

 and medial part of the gland, pass to the angle between the seventh rib and the 

 xiphoid process, where they pierce the fibrous layers of the abdominal wall and join 

 the lymph vessels in the extra-peritoneal fascia of the upper part of the abdomen. It is 

 through those vessels that cancer cells not uncommonly travel from the mamma to the 

 abdomen (Fig. 806). 



Lymph vessels pass also from the deep part of the mammary gland, through 

 the deep fascia and the pectoralis major, and then ascend, along the line of the pectoral 

 branches of the thoraco-acromial artery, to the infra-clavicular region, where they 

 terminate either in the inter-pectoral or the infra-clavicular glands, or in both groups. 

 It is possible that some of those vessels, after piercing the costo-coracoid membrane, 

 may pass directly to the inferior deep cervical glands (Fig. 806). 



It is stated, further, that some of the lymph vessels which issue from the mamma 

 pierce the whole thickness of the thoracic wall and join the lymph vessels which lie 

 in the endo-thoracic fascia, which intervenes between the ribs and the intercostal muscles 

 externally and the pleural membrane internally. 



THE LYMPH GLANDS OF THE THOKAX. 



The lymph glands of the thorax form 5 named groups, with subdivisions. 



(1) Lymphoglandulse Sternales. The sternal lymph glands form two groups 

 each of which lies at the corresponding margin of the sternum along the line of the 

 internal mammary artery. The glands are variable in number (4-18) and in size. 

 They receive afferents from the upper part of the muscles of the abdominal wall, 

 from the diaphragm, from the anterior part of the wall of the thorax, and from the 

 medial portions of the mammae. Their efferents communicate with the upper 

 anterior mediastinal glands and with the inferior deep cervical glands, and they 

 terminate on the right side in the right lymphatic or the right broncho-mediastinal 

 duct and on the left in the thoracic duct. Occasionally, also, they end directly in 

 the internal jugular or the subclavian vein. 



(2) Lymphoglandulse Intercostales. The intercostal lymph glands are lateral 

 and medial. The lateral glands lie in the posterior parts of the intercostal spaces, 

 the medial are placed in front of the heads of the ribs. Their afferents are derived 

 from the boundaries and contents of the spaces. The efferents of the glands of the 

 upper spaces pass either to the posterior mediastinal glarids or to the thoracic 



