The experience of having unsatisfactory results in 2 patients on whom I performed nephropexy six years ago stimulated my interest in the posteriorly located renal pelvis. In the first case, the pain of the patient was not satisfactorily relieved and, in the second case, the kidney had to be removed before the patient had a chance to leave the hospital because of uncontrollable renal pain. In both instances the renal pelvis was observed to be coming from a scooped-out-like depression on the posterior aspect of the kidney. Since this experience, it has been impressive to observe that every patient who has had enough difficulty with ptosis to demand surgical treatment has had this type of kidney.
Twenty-five patients between the ages of 17 to 68 in whom the diagnosis of posteriorly located pelvis has been made have been seen. Of these, 2 were males and 23 were females. Two had