Continence disorders after anal surgery--a relevant problem?

Anal incontinence is a well-known and feared complication following surgery involving the anal sphincter, particularly if partial transection of the sphincter is part of the surgical procedure.

The literature was reviewed to evaluate the risk of postoperative incontinence following anal dilatation, lateral sphincterotomy, surgery for haemorrhoidal disease and anal fistula.

Various degrees of anal incontinence are reported with frequencies as follows: anal dilatation 0-50%, lateral sphincterotomy 0-45%, haemorrhoidal surgery 0-28%, lay open technique of anal fistula 0-64% and plastic repair of fistula 0-43%. Results vary considerably depending on what definition of "incontinence" was applied. The most important risk factors for postoperative incontinence are female sex, advanced age, previous anorectal interventions, childbirth and type of anal surgery (sphincter division). Sphincter lesions have been reported following procedures as minimal as exploration of the anal canal via speculum.

Continence disorders after anal surgery are not uncommon and the result of the additive effect of various factors. Certain risk factors should be considered before choosing the operative procedure. Since options for surgical repair of postoperative incontinence disorders are limited, careful indications and minimal trauma to the anal sphincter are mandatory in anal surgery.