Nick-
If your sphincter is providing enough back pressure, there are a couple of things that can push out stool involuntarily. CT mentioned a spasmodic pouch (“motility issue”), and if your doctor thinks that might be the cause, an antispasmodic (like Bentyl or Levin) could be worth trying. The most common cause of this is pouchitis, but the fact that it looks non-inflamed and Cipro didn’t help suggest that’s not it. If you run out of options, though, a course of Flagyl might be worth a try, just in case it’s pouchitis that doesn’t look like much and doesn’t respond to Cipro.
Bulking up the stool with soluble fiber makes it much easier for the sphincter to hold it back. I suggest you try psyllium first, and if that gives you gas or doesn’t work there are other options (Benefiber, Citrucel, etc.).
Good luck!