THE LYMPHATICS OF THE THORAX 715 



THE LYMPHATICS OF THE THORAX. 



The lymph glands of the thorax may be divided into parietal and visceral the 

 former being situated in the thoracic wall, the latter in relation to the viscera. 



The parietal lymph glands include the sternal, intercostal, and diaphragmatic 

 glands. 



1. The Sternal Glands (lymphoglandula? sternales; internal mammary glands} are 

 placed at the anterior ends of the intercostal spaces, by the side of the internal 

 mammary artery. They derive afferents from the mamma, from the deeper struc- 

 tures of the anterior abdominal wall above the level of the umbilicus, from the 

 upper surface of the liver through a small group of glands which lie behind the 

 xiphoid process, and from the deeper parts of the anterior portion of the thoracic 

 wall. Their efferents usually unite to form a single trunk on either side; this may 

 open directly into the junction of the internal jugular and subclavian veins, or 

 that of the right side may join the right subclavian trunk, and that of the left 

 the thoracic duct. 



2. The Intercostal Glands (lymphoglandulce intercoslales) occupy the posterior 

 parts of the intercostal spaces, in relation to the intercostal vessels. They receive 

 the deep lymphatics from the postero- lateral aspect of the chest; some of these 

 vessels are interrupted by small lateral intercostal glands. The efferents of the 

 glands in the lower four or five spaces unite to form a trunk, which descends and 

 opens either into the cisterna chyli or into the commencement of the thoracic duct. 

 The efferents of the glands in the upper spaces of the left side end in the thoracic 

 duct; those of the corresponding right spaces, in the right lymphatic duct. 



3. The Diaphragmatic Glands lie on the thoracic aspect of the diaphragm, 

 and consist of three sets, anterior, middle, and posterior. 



The anterior set comprises (a) two or three small glands behind the base of the 

 xiphoid process, which receive afferents from the convex surface of the liver, and 

 (6) one or two glands on either side near the junction of the seventh rib with its 

 cartilage, which receive lymphatic vessels from the front part of the diaphragm. 

 The efferent vessels of the anterior set pass to the sternal glands. 



The middle set consists of two or three glands on either side close to where the 

 phrenic nerves enter the diaphragm. On the right side some of the glands of this 

 group lie within the fibrous sac of the pericardium, on the front of the termination 

 of the inferior vena cava. The afferents of this set are derived from the middle 

 part of the diaphragm, those on the right side also receiving afferents from the 

 convex surface of the liver. Their efferents pass to the posterior mediastinal glands. 



The posterior set consists of a few glands situated on the back of the crura of 

 the diaphragm, and connected on the one hand with the lumbar glands and on 

 the other with the posterior mediastinal glands. 



The superficial lymphatic vessels of the thoracic wall ramify beneath the skin 

 and converge to the axillary glands. Those over the Trapezius and Latissimus 

 dorsi run forward and unite to form about ten or twelve trunks which end in the 

 subscapular group. Those over the pectoral region, including the vessels from the 

 skin covering the peripheral part of the mamma, run backward, and those over 

 the Serratus anterior upward, to the pectoral group. Others near the lateral margin 

 of the sternum pass inward between the rib cartilages and end in the sternal glands, 

 while the vessels of opposite sides anastomose across the front of the sternum. A 

 few vessels from the upper part of the pectoral region ascend over the clavicle to 

 the supraclavicular group of cervical glands. 



The Lymphatic Vessels of the Mamma originate in a plexus in the interlobular 

 spaces and on the walls of the galactophorous ducts. Those from the central part 

 of the gland pass to an intricate plexus situated beneath the areola, a plexus which 

 receives also the lymphatics from the skin over the central part of the gland and 





