Kidneys are important parts of the body. Their function is to remove waste and toxic substances from the blood and passing out the liquid called urine. The journey of urine starts from the kidney to the bladder through ureter and then exit through the urethra. If there are more of certain waste materials in the urine, these substances form crystals and then finally the stones.
The site of the pain depends on the location of the stones which may vary from kidney to any of the urine tubes i.e. ureter or urethra. The pain occurs in the form of renal colic and is usually gripping type of unbearable ache.