Just days after a source said "American Idol" champ Phillip Phillips? was going to skip? a much-needed kidney surgery, a spokesperson for the 21-year-old singer said he underwent a procedure on Wednesday and is now resting comfortably.

"Surgery went well," a spokesperson told MTV News about the reportedly six-plus hour surgery in Los Angeles to remove kidney stones so large Entertainment Weekly reported that there was "no chance" he could have passed them on his own. "He's resting and will be ready for the 'Idol' tour kickoff in July!" the rep added about the 45-day summer outing slated to launch on July 6 in Detroit.

When you think about it, it's pretty incredible that Phillip Phillips was able to not only hang in, but win "American Idol" season 11 given the pain he was in from chronic kidney problems. The singer struggled with kidney stones during his entire run on "Idol," and had a stent implanted in one of his kidneys in March to prevent blockage, and allow him to keep competing on the show.

Phillips reportedly went through eight surgeries from the time "Idol" began in January until the May 23 finale, but this week's procedure could help alleviate a lot of the pain he's been suffering, according to a leading nephrologist.

"Kidney stones are fairly common ... occurring in more than 10 percent of men and 5 of women and once they've formed one, they're likely to form another," said Dr. Gary C. Curhan, a professor of medicine and editor-in-chief of the Clinical Journal of the American Society of Nephrology. Typically made up of calcium, stones can be formed for a number of reasons, said Curhan, who is not treating Phillips and has no firsthand knowledge of his case. Those reasons include low fluid intake (which leads to concentrated urine), dietary factors, certain medications and, in some cases, an anatomical predisposition to forming them.

He also noted that the stent is a temporary measure and is typically very painful, but allows urine to continue flowing until the swelling in the ureter (the tubes that move urine from the kidneys to the bladder) goes down. Phillips was slated to have reconstructive kidney surgery right after his "Idol" win, but, according to TMZ the procedure was postponed because of a bad sinus infection that triggered a high fever. TMZ also reported earlier that Phillips suffers from a serious congenital kidney condition that produces stones so large they cannot pass and which has seriously damaged his right kidney.

Curhan, who spoke to MTV News before Phillips had the surgery, said most stones will pass on their own, but in doing so will cause a huge amount of pain. Others are too big and require removal by a urologist, either by breaking them up with shockwaves or using a surgical tools to break them up internally or pull them out. He noted that it's rare for stones to form quickly, as they normally take months, or years and multiple surgeries in a short period of time is also unusual.

Cases where stones continually form and are hard to pass are typically caused by an anatomical difference that causes the kidney to drain urine improperly, which predisposes the patient to stones. "If aggressive therapy is not working, you have to have surgery to change the anatomy to help it drain better," he said. "There is risk involved in the procedure [surgery], but not treating it can also cause risk," he said.

...