5 years ago 1/3 of lower internal sphincter muscle was cut at 3 O'CLOCK position to cure anal fissure by a colorectal surgeon  But still after surgery it seems to me that my anal opening is tight and it doesn't open completely . Another problem is 10 days ago again I have developed anal fissure and conservative treatment has failed to cure anal fissure . So has any other surgery than Lateral anal sphinctertomy to cure this problem from root so that in future it doesn't recur for occasional hard stool ??