A colectomy and subsequent ileostomy are surgeries that involve removing the large bowel (colon) and creating an opening in the abdomen for food waste to go through the small intestine and out of the body through this opening, into a stoma bag, bypassing the rectum and anus as methods of food excretion.
The patient may have the option of a stoma reversal, which would attach the small intestine to the rectum, giving rise to the reestablishment of the gastrointestinal tract.
My question: Given that the patient can go a long time before getting a reversal, i.e. a long time without making use of their rectum/anus, both of which involve muscles that will not have "exercised" for a long time, is it possible that the muscles involved in the rectum's or anus' function can atrophy in that time? And what kind of consequences would that entail for a patient?