1350 



THE URINOGENITAL OUGANS 



abdomen. On the left side it is in contact, at its upper part, with the spleen 

 (Fig. 1087). 



The internal border (margo medialis) (Figs. 1088 and 1089) is concave, and is 

 directed forward, inward, and a little downward. It presents a deep longitudinal 

 fissure, bounded by a prominent overhanging anterior and posterior lip. This 

 fissure is named the hilum (hilus renalis) (Fig. 1089), and allows of the passage 

 of the vessels, nerves, and ureter into and out of the kidney. 



At the hilum of the kidney the relative position of the main structures passing 

 into and out of the kidney is as follows: The vein is in front, the artery in the 

 middle, and the duct or ureter behind and toward the lower part (Fig 1088). 

 By~a4tiiuwli!dg'i! of these relations LluTstudent may distinguish between the right 

 and left kidney. The kidney is to be laid on the table before the student on its 

 posterior surface, with its lower extremity toward the observer that is to say, 

 with the ureter behind and below the other vessels; the hilum will then be directed 

 to the side to which the kidney belongs. Frequently, however, the branches of 

 both artery and vein are placed behind the ureter. 



Extremities. The superior extremity (extremitas superior} (Figs. 1088 and 

 1089) is directed slightly inward as well as upward, being situated about 4 cm. 

 from the mesal plane. It is thick, broad, bulky, and rounded, and is surmounted 



by the suprarenal gland (Fig. 1094), which 

 covers also a small portion of the anterior 

 surface. 



The inferior extremity (extremitas inferior) 

 (Figs. 1088 and 1089), directed a little out- 

 ward as well as downward, is smaller and 

 thinner and usually more pointed than the 

 superior. It is situated about 6 cm. from the 

 mesal plane, and extends to within two inches 

 (5 cm.) of the crest of the ilium. 



Fixation of the Kidney (Figs. 1092 and 

 1093). The kidney and its vessels are em- 

 bedded in a mass of fatty tissue termed the 

 capsula adiposa (perirenal fat), which is thickest 

 at the margins of the kidney and is prolonged 

 through the hilum into the renal sinus. The 

 kidney and the capsula adiposa are enclosed in 

 a sheath of fibrous tissue continuous with the 

 subperitoneal fascia, and named the fascia 

 renalis. At the outer border of the kidney the 

 fascia renalis splits into an anterior and a pos- 

 terior layer. The anterior layer is carried in- 

 ward in front of the kidney and its vessels, and 

 is continuous over the aorta with the correspond- 

 ing layer of the opposite side. The posterior 

 layer extends inward behind the kidney and 

 blends with the fascia on the Quadratus lumborum and Psoas muscles and through 

 this fascia is attached to the vertebral column. At the upper margin of the supra- 

 renal gland the two layers of the fascia renalis fuse, and unite with the fascia of 

 the Diaphragm; below they remain separate, and are gradually lost in the sub- 

 peritoneal fascia of the iliac fossa (Fig. 1092). The fascia renalis is connected 

 to the fibrous capsule of the kidney by numerous trabeculse, which traverse the 

 adipose capsule and are strongest near the lower end of the organ. The perirenal 

 fat does not look like the fat in other regions, but is soft, delicate, and of a canary- 

 yellow color. Behind the fascia renalis is a considerable quantity of fat which 



FIG. 1094. Vertical section of kidney. 



