What typically causes renal colic?

Obstruction. Renal colic can be very severe kidney pain in the flank area caused by obstruction. This is typically caused bt kidney stones but can also be cauised by other obstructing processes sucv as bleeding, blood clots, and obstruction from cancer.
Kidney stone. Colic is pain described by patients passing kidney stones, generally very painful as the stone travels the passage from the kidney to the bladder, and may get stuck sometimes. Pain is described in the loin area ie below the ribs in the back and travels to the front of the tummy.
Obstruction/blockage. Obstruction to urine flow either from a kidney or ureteral stone or obstructing blood clot, an anatomic obstruction or a combination of both. Anatomic obstructions can occur at either the kidney level (uretero-pelvic junction) bladder level (uretero-vesical junction) or along the ureter from a stricture (narrowing). Most common is renal colic from a stone & said to be more painful than childbirth.
Renal colic. I tell my pts with renal colic that it is a urine traffic jam causing increased pressure in the system....This pressure increase from blockage causes the pain from stretching the system....
Renal colic. Blockage of the ureter with a stone causes it to try and relieve the block and gets it into spasm. This causes colic.