I had it done a couple of years ago. They inserted a tube from below and sound blasted then removed the broken up pieces. It was painful afterwards but not for long. A tube was left in the uritor(spelling) for 3 or 4 weeks to allow healing then removed painlessly without anesthesia. Stuck close to home while the tube was in because of incontinence.

The kidneys are situated in the back and higher up, so going through the back is easier access. Hope all goes well for you