by jr2 » 14 Jan 2014, 14:06
It could be both sphincters giving you grief. It could also be other muscles that are involved in BMs such as the PC muscle and the levator ani muscles. When stool descends from the rectum, the internal sphincter automatically relaxes to let the stool pass through. Then, the external sphincter, the one you have control over, is the muscle you consciously squeeze closed until you can get to a bathroom. When you have a fissure, the internal sphincter usually is tight or in spasm. So, what could be happening is that you are experiencing the automatic relaxing of the internal sphincter coupled with an initial conscious relaxing of the external sphincter, which allows the beginning of the BM, but then a kind of unconscious bracing and anxiety sets in and is causing both muscles to tense in response to that. Do you feel you are achieving soft enough stools to pass through right now? Also, have you tried a squatting, or semi squatting position when you have a BM? Elevating your feet on a footstool and leaning forward helps the pelvic floor tremendously when it comes to a more natural relaxation of the muscles involved in BMs. Also, practicing some deep, slow belly breathing can help you to relax your nervous system that controls the muscles in the area.