So, this is the deal:
Once somebody, or anybody, has any sort of abdominal surgery, and especially intestinal surgery, internal scar tissue forms. This scar tissue is called adhesions. They are caused by the trauma of surgery, foreign bodies, infection, maybe even air getting inside...
Think of these adhesions like gum in the works. They are stiff bands of tissue that attach organs to places that were not intended to be attached to. Your intestines were designed to be able to move about, suspended happily from the back wall of your abdomen. Adhesions are like rubber bands getting in the way.
Some people form few of these adhesions, some a lot. But, even if you have a lot of adhesions, it does not mean they will cause problems, or that if you only have a few, they won't cause problems. Just like the freeway, it only takes one stalled car to muck up the whole system and make things back up for miles.
You may think you are doomed, but these adhesions can soften and loosen up over time, and your gut can learn to work around them. If they are terribly problematic, they can release them through surgery. But, the Catch-22 is that more surgery can cause more adhesions, so they don't go there except as a last resort.
Bert is correct that the ileostomy site is the most likely spot for adhesion related obstructions.
Hopefully, this explanation makes some sense to you.
Jan