I have a long history with pelvic floor dysfunction that has caused my rectal muscles to be abnormally spastic and tight and have caused routine straining during bowel movements. I keep my stool soft with water, fiber and miralax, but even with soft stool, I still typically have difficulty with easy bowel movements. I have had at least 4 recurrences of anal fissures over the past 6 years that have all healed with conservative treatment. I am now dealing with another fissure that doesn't seem to be healing like the others. Based on my history with an underlying pelvic floor condition that was not the result of fissures, but rather vice versa, I am curious how LIS affected straining during bm's. I know that LIS is supposed to stop the spasm and allow the fissure to heal, but if a fissure is the result of straining and the constant straining during bm's is preventing healing, does LIS do anything to correct this issue and make bm's easier with less straining. If anyone has had LIS or knows of someone who has had LIS can you offer me some insight as to how this affected your ability to have easy non-straining bm's? Thank you.

The best tip I have ever picked up from this board is sooo simple. Stretch your feet out in front of you when you sit on the toilet. I have also leaned back against the toilet lid. Being a little graphic (apologies) it seems the feces slide out instead of having to be pushed. I heard it a few times but with my hard head I did not try it until I had tried everything else. I had LIS and can still hurt myself unless my BM is soft but it is much less strain since the surgery. Hope you find an answer that works for you.

Can't really answer as to PFD relation as I have no experience with it. But LIS relaxes the muscle, which eliminates much of the tightness, albeit temporarily. It's my understanding that, while it will regain strenghth and tightness over time, it will never be quite as tight as prior to surgery . . . ymmv.
As for straining, the only thing I can pass on is a puece of advice I received from another board and that is ti "Let sh%t happen." We tend to want to finish on our own schedule and sometimes push or strain to varying degrees to get it done. I've learned to wait until I need to go and then once on rhe toilet, give it time. My body has gotten on a schedule I can't seem to break. Approaching 5am, my body starts letting me know I gotta go. Once I get up, got maybe 5 minutes to get on toilet, but its usually my first stop. First part comes out then I wait. Usually 5-6 min later here comes more. I just breathe and let it come. That may happen once more before I know Im done. Then I do an initial cleaning and hop in the tub (started water running when I sat down) for a soak. I had LIS about 6 weeks ago and have had no pain or bleeding since then. If you're concerned about actually sitting that long, just do an initial cleanup and walk around a bit til the next portion is ready to exit and sit back down for round two.
The schedule works for me and is consistent except for the rare time I have to go later in the day, which is about 1-2 per week.
One other thing that may help . . . Immediate post op, my CRS instructed to have 2-3 tbspn of mineral oil (in addition to softeners, water, fiber, etc.) 2-3 times per day. You could do one dose eaxh morning. Its a lubricant and may help, but I dont know about the affect of long-term use. You'll have to ask about that.
I hope this helps.

I agree with Jo. LIS will relax that muscle so I can't see how it wouldn't help. My BM's have been much easier and complete since having the surgery. It's been well over a year now and I still have better BM's then even pre-fissure days.