"A Study of the Etiology of Floating Kidney, With Suggestions Changing the Operative Technique of Nephropexy.

The condition of nephroptosis has been the subject of much thought and speculation for many years, and its etiology widely discussed. The facts that 85 per cent. of all cases occur in women and that fifteen kidneys of the right side, to one of the left, become movable, and that the left kidney is almost never singly displaced, and when it does become. displaced gives no such serious symptoms as are attributed to the rightsided displacement; form a sort of tough entree beside the equally tough piece de resistance the fact that the kidney does come down of the etiologic repast.

The causes of these conditions have never, in the opinion of the writer, been satisfactorily explained in the literature at his command, so that when an incident occurred to draw his attention to this question he followed the lead, so to speak, and now will attempt to give a preliminary report of his work along the lines mentioned. The report must, of necessity, be unfinished at this writing, as sufficient time has not yet elapsed to prove certain operative work by the test of permanence, beside, more work on the cadaver is desirable to establish, by the proof of greater numbers, the facts already apparently in evidence.

On December 17, 1903, while operating on a young girl of sixteen years of age, for appendiceal disease, at the Solvay Hospital in Delray, the writer accidentally discovered that the right kidney, which was normally placed, could be easily pulled down and held in a firm position of complete prolapse, by making traction on the cecum. This led to farther observation on the etiology of displaced loose or floating kidney, both on the cadaver and the living subject, and afterwards, as a result of those observations, to efforts to devise an operation that should have for its object the retention of the kidney in its normal position as well as the anchoring of the ascending colon in such a manner as to remedy the prolapse of the cecum, which usually obtains in these cases, so that it should not exert further traction on the kidney and, through it, on the duodenum and renal vessels. The object of this address is to record the results, though unfinished, of these observations.

The fact that the kidney in question could be pulled down and held firmly in this position by traction on the cecum and ascending colon was an indication that there exists a more firm and positive attachment of this viscus to the kidney than is generally believed. Gerrish says: "The non-serous areas (of the kidney) are connected with the various organs with which they are related by areolar tissue." This author also says of the supports of the kidneys: "The kidneys are kept in place by their vessels, the peritoneum, and the abundant fatty tissue in which they are embedded." Another (Ref. Hand Book of the Med. Sciences) says: "The chief support of the kidneys is the fibrous capsule which surrounds the gland as far as the hilus and sends a firm prolongation behind the renal vessels with the sheath of the aorta, and the fascia, which covers the pillars of the diaphragm. The fibrous prolongation acts as a suspenscry ligament to maintain the kidney in position."

We are still farther told that "the kidneys are held in place mainly by the connections of the peritoneum with the perinephric fat." (Am. Text Book of Surgery.)

A third capsule has been described by Grota, called the renal or perirenal fascia, lying outside the fatty capsule. Its anterior layer passes across the front of the kidney and meets the same layer of the opposite kidney. The posterior layer is attached to the periosteum of the vertebrae. This fascia is adherent anteriorly to the peritoneum. This is apparently a continuation of the parietal subperitoneal fascia and should also tend to support the kidney to a limited extent.

Thus the supports of the kidney are seen to be of a rather uncertain and indefinite character, and yet apparently sufficient to maintain an organ weighing but from four to five ounces (Gerrish). Why this small organ, weighing so little, is pulled or pushed, as the case may be, out of its normal position, and why the right one so much more frequently than the left, are questions that have many and diverse answers by many and diverse authorities. The etiologic factors, as outlined by the many recorded articles on this subject, touch every organ within the abdominal cavity, from the liver and stomach to the uterus, and beyond and outside the abdomen to the perineum, and at last, as though there were no farther organs to condemn for the crime of the abduction of their inoffensive, hard working associate, the whole body, or rather its shape, is at last attacked and charged with the offense.

Among these almost numberless opinions which are more or less. confusing to the investigator, some are exceedingly ingenious and interesting, if not altogether plausible. A few of them are as follows:

International Text Book of Surgery: Atrophy of adipose capsule; repeated pregnancies, enteroptosis where the displaced intestines make. traction on the kidney; pressure on the waist by corset or shirt band, seidom by traumatism.

Am. Text Book of Surgery: If the perinephric fat is absorbed during acute disease or from long continued ill health the organ can move more freely, and by its weight elongates the parietal folds which in other cases are abnormally long and lax. The kidney may also be dislocated by trauma. Most common in poorly nourished females who have borne children, the scarcity of fat and the relaxation of the abdominal walls following pregnancy acting as predisposing causes.

Faecal impaction as a factor in the causation of floating kidney is mentioned by Frank Griffith (Med. Record, July 20th, 1901), who reports a case in a woman of 25 in which the long continued weighing. down of the colon with faecal accumulations was active in the production of the kidney condition, and when it was removed a prompt recovery took place.

As showing the intimate connection between the lower bowel and the kidney the writer cites a case of loosened right kidney in a young. woman who began to suffer from a stubborn colitis which defied treatment until the performance of nephrorrhaphy, when almost at once the bowel symptoms disappeared.

Reference Hand Book of the Med. Sciences: The kidney is normally held in place by a fascial prolongation from its fibrous capsule to the spinal column, and also, according to Walkoff and Dilitzin, by the shape of the cavity in which the kidney lies. The normal cavity is funnelshaped. In a case of movable kidney the recess is shallow and more cylindrical. Other alleged causes are the reduction of the intra-abdominal pressure by relaxation of the abdominal walls; tight lacing, especially if so carried out as to compress the ribs, and muscular strains and blows. M. L. Harris (Jour. Am. Med. Assn., June 1, 1901), cites the following as the usually accepted causes:

1. Repeated pregnancies.

2. Prolapse of the uterus and vagina with laceration of the perineum. 3. Retrodisplacements of the uterus by drawing on the ureters. 4. The rapid absorption of perirenal fat as may occur in wasting disease.

5. Drawing on the kidneys by the transverse mesocolon in enteroptosis or Glenard's disease.

6. The relaxation of the abdominal walls which follows the removal of abdominal tumors, as ascitic accumulations.

He shows these etiologic factors to be fallacious, and conclusions are presented as follows:

1. The essential cause of movable kidney lies in a particular body form.

2. The chief characteristics of the body form a marked contraction of the lower end of the middle zone of the body with an elimination of the capacity of this portion of the body cavity.

3. The diminution of capacity depresses the kidney so that the constricted outlet of the zone comes above the center of the organ and all acts, such as coughing, straining, lifting, flexions of the body, etc., which tend to adduct the lower ribs, press on the appendage of the kidney and carry it still further downward.

4. It is the long continued repetition in a suitable body form, of these influences, which collectively may be called internal trauma, that gradually produces a movable kidney.

In support of the above table he cites a number of cases. By some great stress is laid on the effect of the modern dress as an etiologic factor in the displacement of the kidney in women. Kuster does not agree with this, as he finds the Egyptian women, who wear loose clothing, have floating kidneys.

After a consideration of the foregoing literature of the subject, the writer was forced to the conclusion that the kidney of his patient was pulled down by the adhesion of the peritoneal attachment or mesentery of the colon to the fatty capsule of the kidney, and yet the apparent firmness of the attachment was a contraindication. With the object of test ing this point, three cases of floating kidney were operated upon. The peritoneal cavity was entered through the usual incision in the loin, the redundant mesentery gathered up and attached to the transversalis fascia close to the twelfth rib, at the upper edge of the wound. In the first case, which was an extreme one of ptosis, having had Dietl's crises for

several years, the ease with which the operation was performed, the amount of slack mesenteric tissue brought out and attached, and the immediate result which it had of entirely replacing the kidney so it could not be pushed down into the abdomen, was very encouraging.

In the second and third cases, however, in both of which the displacement was less pronounced, there was practically no mesentery, as was present in the first case, so that its fixation seemed to promise less. However, while drawing the mesentery out and making efforts to push the bowel down, away from the kidney, it was observed, in both cases, that there was a cord-like structure passing downward from the lower pole of the kidney, which prevented the separation of the kidney and bowel. This was included with the mesenteric tissue and attached with it. Further investigation of the literature failed to enlighten the writer as to the presence of any tendinous prolongation from the lower pole of the kidney, so farther investigation was made on the cadaver, the dissection being as follows: The whole upper half of the abdominal parietes being incised and turned downward, the cecum, ascending colon, with hepatic flexure and kidney on the right side, and part of the descending colon with splenic flexure and kidney on the left side, were removed, the dissection being made from below upwards and the organs. removed together in such a manner as not to interfere with their normal attachments to each other. On turning the specimens over, the posterior surface of bowel and kidney, of each side, showed a similar formation of tendinous attachment to each other. This was found to be formed by the gathering together of fine longitudinal fibres from the fibrous network which forms the frame work of the fatty capsule. The tendinous ridge, formed by its attachment to the posterior surface of the ascending colon, could be followed easily, between the peritoneal reflections down to the margin of the lower peritoneal attachment of the bowel, and close to the junction of the ileum-in fact, near the point of the so-called origin, in the female subject, of the suspensory ligament of the ovary. This ligamentous continuation of the framework of the fatty capsule is probably the tissue left in the track of the ovary, or testicle, in its descent from its place of origin in the Wolffian body, high up near the kidney.

Nagel says: "The ligamentum suspensorium ovarii springs developmentally from the phrenic ligament of the kidney, being therefore situated on the posterior abdominal wall."

So much for its probable cause of origin, which is interesting from an embryologic standpoint and is worthy of further study, but the important point is: How much mischief is this little remnant of embryologic life doing; how much of an etiologic facter is it in the production of displaced kidney? The anatomist tells us that the fatty capsule does not develop till after the tenth year. This is no doubt true as regards the fat of the capsule, but it is not true if applied to the fine fibrous network which forms the frame of the so-called fatty capsule, as this is found to be present in the newly born infant, enveloping the kidney and passing downward, its fibres converging at the lower pole into a more or less ligamentous structure which is inserted into the posterior wall of the ascending (or descending) colon, in exactly the same manner and

proportion as in the adult. This the writer has also demonstrated in the cadaver.

Specimens illustrating this fact are herewith submitted, one of which, consisting of uterus, fallopian tube, ovaries, ascending and descending colon and kidneys, connected together by their normal attachments, also shows the apparent continuation of this nephrocolic ligament with the suspensory ligament of the ovary. In these small subjects the nephrocolic attachment was found much the more pronounced on the right side.

This ligamentous union of the kidney and bowel the writer claims is the most important factor in the etiology of nephroptosis. The full cecum in its efforts to push its contents upwards, is making traction downwards, which pulls the kidney with it, by reason of this attachment. The cecum is constantly making counter-extension, as it were, with its fixed point above, while the descending colon makes its counter-extension upwards with its fixed point below. This will explain the greater relative frequency of the displacement of the right kidney over the left, which is given as above 15 to 1 (Reference Hand Book Medical Sciences, P. 357)

So far as the writer knows, there has not heretofore been given any adequate explanation of the cause of this great difference. The pulling of the right kidney down by this definite and positive form of traction would also account for certain symptoms which so frequently accompany the displaced kidney and which are of a "digestive" and "nervous" character, and which owe their activity to the fact that the fatty capsule of the kidney is adherent, at its inner aspect, to the descending portion of the duodenum. Traction on this viscus by the full cecum pulling downward on the kidney, causes a kinking of the gut with the production of the symptoms referred to. The cecum being the starting point of the forward movement of the colonic contents, and a cul de sac from which its contents must invariably go in one direction, and that upward, or impaction result, the consequence is that impaction due to torpidity is frequent, the cecum becomes heavy and pendant, dragging more and more on its attachments by its sheer weight. Add to this Nature's violent efforts necessary to force the contents upward, and we have a simple and also an adequate explanation for the displacement of the right kidney, as well as the presence of the prolapse of the ascending colon, which is its usual accompaniment. The properly applied abdominal band or truss relieves symptoms attributed to the floating kidney, not because it raises the kidney, but because it raises the cecum and so prevents traction on the renal vessels and duodenum.

A kidney stripped of its fatty capsule and fixed by adhesion to the muscular parietes so frequently fails to relieve symptoms because the continuity of attachment between the duodenum and cecum still remains through the fatty capsule, and the action of the prolapsed cecum continues to exert its influence on the duodenum and stomach, through it.

If the contention of the writer is correct, that this ligamentous union of kidney and bowel is the principal cause of the pathological condition under question, then surgical therapeutics must be altered in such ways