THE KIDNEYS. 1135 



the renal artery and its branches, but their exact mode of termination is not 

 known. 



The lymphatics consist of a superficial and deep set which terminate in the 

 lumbar glands. 



Connective Tissue, or Intertubular Stroma. Although the tubules and vessels 

 are closely packed, a certain small amount of connective tissue, continuous with 

 the capsule, binds them firmly together. This tissue was first described by Goodsir, 

 and subsequently by Bowman. Ludwig and Zawarykin have observed distinct 

 fibres passing around the Malpighian bodies, and Henle has seen them between 

 the straight tubes composing the medullary structure. 



Surface Form. The kidneys, being situated at the back part of the abdominal cavity and 

 deeply placed, cannot be felt unless enlarged or misplaced. They are situated on the confines 

 of the epigastric and umbilical regions internally, with the hypochondriac and lumbar regions 

 externally. The left is somewhat higher than the right. According to Morris, the position of 

 the kidney may be thus defined: Anteriorly: "1. A horizontal line through the umbilicus is 

 below the lower edge of each kidney. 2. A vertical line carried upward to the costal arch from 

 the middle of Poupart's ligament has one-third of the kidney to its outer side and two-thirds to 

 its inner side i. e. between this line and the median line of the body." In adopting these lines 

 it must be borne in mind that the axes of the kidneys are not vertical, but oblique, and if con- 

 tinued upward would meet about the ninth dorsal vertebra. Posteriorly : The upper end of the 

 left kidney would be defined by a line drawn horizontally outward from the spinous process of the 

 eleventh dorsal vertebra, and its lower end by a point two inches above the iliac crest. The right 

 kidney would be half to three-quarters of an inch lower. Morris lays down the following rules 

 for indicating the position of the kidney on the posterior surface of the body : "1. A line par- 

 allel with, and one inch from, the spine, between the lower edge of the tip of the spinous pro- 

 it' the eleventh dorsal vertebra and the lower edge of the spinous process of the third 

 lumbar vertebra. '2. A line from the top of this first line outward at right angles to it for 

 2f inches. 3. A line from the lower end of the first transversely outward for 2f inches. 4. A 

 line parallel to the first and connecting the outer extremities of the second and third lines just 

 described. 



The hilum of the kidney lies about two inches from the middle line of the back, at the level 

 of the spinous process of the first lumbar vertebra. 



Surgical Anatomy. The kidney is imbedded in a large quantity of loose fatty tissue, and 

 is but slightly covered by peritoneum ; hence rupture of this organ is not nearly so serious an 

 accident as rupture of the liver or spleen, since the extravasation of blood and urine which 

 follows is outside the peritoneal cavity. Occasionally the kidney may be bruised by blows in the 

 loin or by being compressed between the lower ribs and the ilium when the body is violently bent 

 forward. This is followed by a little transient haematuria. which, however, speedily passes off. 

 Occasionally, when rupture involves the pelvis of the kidney or the commencement of the ureter, 

 this duct may become blocked, and hydronephrosis follow. 



The loose cellular tissue around the kidney may be the seat of suppuration, constituting 

 parinephritie <il>*c?ss. This may be due to injury, to disease of the kidney itself, or to extension 

 of inflammation from neighboring parts. It may burst into the pleura, constituting empyema ; 

 into the colon or bladder ; or may point externally in the groin or loin. Tumors of the kidney, 

 of which, perhaps, sarcoma in children is the most common, maybe recognized by their position 

 and fixity ; by the resonant colon lying in front of it ; by their not moving with respiration ; and 

 by their rounded outline, not presenting a notched anterior margin like the spleen, with which 

 they are most likely to be confounded. The examination of the kidney should be bimanual ; 

 that is to say. one hand should be placed in the flank and firm pressure made forward, while the 

 other hand is buried in the abdominal wall just external to the semilunar line. Manipulation of 

 the kidney frequently produces a peculiar sickening sensation, with sometimes faintness. 



The kidney is mainly held in position by the mass of fatty matter in which it is imbedded 

 and over which the peritoneum is stretched. If this fatty matter is loose or lax or is absorbed, 

 the kidney may become movable and may give rise to great pain. This condition occurs, there- 

 fore, in badly-nourished people or in those who have become emaciated from any cause, and is 

 more common in women than in men. It must not be confounded with the floating kidney : this 

 is a congenital condition due to the development of a meso-nephron, which permits the organ to 

 move more or less freely. The two conditions cannot, however, be distinguished until the 

 abdomen is opened or the kidney explored from the loin. 



The kidney has, of late years, been frequently the seat of surgical interference. It may be 

 exposed for exploration or the evacuation of pus (nephrotomy) ; it may be incised for the 

 removal of stone (nephro-lithotomy) ; it may be sutured when movable or floating (nephrorraphy) ; 

 or it may be removed (nephrectomy). 



The kidney may be exposed either by a lumbar or abdominal incision. The lumbar opera- 

 tion is the one which is generally adopted, unless in cases of very large tumors or of wandering 

 kidneys with a loose meso-nephron, on account of the advantages which it possesses of not 

 opening the peritoneum and of affording admirable drainage. It may be performed either by 

 an oblique, a vertical, or a transverse incision. Perhaps the preferable, as affording the best 



