What about people with stomas from colorectal cancers, Crohn’s disease, diverticuliitis, etc? In these cases, the stoma, or ostomy (intestine protruding through the abdominal wall instead of being attached to the rectum/anus) has no sphincter rendering the ostomate completely incontinent for both gas and feces. More so for the right sided ileostomates from Crohn’s, Colitis and others versus the left sided colostomate, usually cancer related and slightly less active. Many stomas are permanent and irreversable. Ostomates rely on the use of an assitive device like colostomy bags. What should an osromate do regarding tefillin and the issue of uncontrolable gas/incontinence?
People that (lo aleinu) have to use a colostomy bag, may put on tefillin, and daven and learn, however before putting davening and putting on his tefillin he should make sure that the pipe and bag are washed and clean, and covered.
Tzitz Eliezer 9-6, explains that it isn’t considered like refuse in the place that it exits, because in this situation it doesn’t smell that much, (look there for his explanation). Also see Nishmas Avrohom vol. 1 76-9 (1) pg. 69-70, that R’ Ezriel Auerbach shlit”a said that this is also the opinion of R’ Eliyashiv zt”l. Besides it isn’t clear that there is anything in the bag at this point, see Minchas Yitzchok 6-11,12.