Hi K.!
My son, too, had an undescended testicle. At his 2 year appt it was discovered and we consulted with a urologist (Dr Ali Abadi) and did the surgery at Children's West. The urologist will feel around his abdomen and try to work the testicle down to see if it springs back up right away or if it's "hyperactive" and goes up and down frequently. Prior to surgery we did not know if he had just one undescended or both but it ended up just being the one side. They did a small incision on his testicle sack and go in with what they describe as a small crochet hook to get ahold of it and bring it down. He also had a small incision on his abdomen. His testicle was bruised for a bit, but other than that, nothing major. It didn't affect his behavior at all, he was himself the minute we got home which was hard because as you can imagine at 2 years old was quite active!
We really liked Dr. Ali Abadi and Children's West. He was the consulting urologist at Park Nicollet in St Louis Park and we liked him and also had a friend whose daughter saw him for urology and they liked him, too.
Hope all goes well!
M.