Kidney stones that are excluded all enter the ureter, and there are three physiological strictures in the ureter, and the stones generally rest in three physiological strictures. The first is the ureteral connection of the renal pelvis, the second is the location of the ureter across the iliac vessels, and the third is the connection between the ureter and the bladder, also known as the interbladder wall segment, which is easier for stones to stay in all three places because the diameter of these three places is smaller than the normal ureter, especially the connection between the ureter and the bladder, which is the narrowest part of the ureter. If the stone is discharged into the ureter, it often stays in this area, which will cause obvious pain or obvious urinary tract irritation, and needs to be examined and treated with extracorporeal shock wave lithotripsy or medication to remove the stone as soon as possible. In rare cases, the stones may remain for a long time because of adhesions to the surrounding tissues or inflammatory polyps, which may require further surgery to break up the stones and expel them from the body.