I am not a doctor but I have lived through the nightmare your sister has gone thru. I went to my doctor for over a YEAR describing excruciating back pain and explained how bad it was to go to the bathroom. I finally went to a gastrointestinal doc and had a colonoscopy done. Guess what? I was Stage Four rectal cancer that had metasticized to my lymph nodes and liver. I had two lenthy surgeries and am permanently on an ostomy bag. I am getting used to the bag and am sooooo glad I am not in pain anymore. I even painted and decorated my bath different because it held too many bad memoies for me. I was under the impression that if it was the rectum muscle that thru radiation it would pretty much damage the muscle so you could not use it anymore. I had radiation mainly to shrink the size of the tumor for the operation not in hope that I would be back to normal, but to kill the tumor. Your sister definately needs a second opinion. I worry for her and I do know her pain to be tooooo real and it is horrible. My thoughts and prayers are with her and her caring family. I am glad she has someone as thoughtful a sister as you to help her out.
Anne :O)
The symptoms are not normal. Did you sister have radiation which may make healing and sphincter function abnormal. Your sister should return to her surgeon with these complaints and she should have a scope of that area, measurements made of the anus muscle sphincter and perhaps a CT scan ( to make sure that there are no other reasons such as cancer recurrence)
If the original surgeon is unable to help, obtain all of her records, operative and path reports, xrays and seek a second opinion.