[Clinic and therapy of anal fissure (author's transl)].

A distinction has to be made between primary and secondary anal fissure. If a secondary fissure is present, the underlying disease has to be treated in the first place. Surgery is the therapy of choice of chronic primary fissure; digital dilatation and sphincterotomy are used in most of these cases. Both methods were applied in a controlled, randomized study; results indicate that subcutaneous lateral sphincterotomy is to be preferred, since rates of postoperative incontinenece and of relapses are lower.