[Update on incisional hernia. Parastomal hernia].

Parastomal herniation is a frequent complication when an artificial anus is constructed. As a tunnel through the abdominal wall is nonphysiological, there is an inherent trend to enlargement of the aperture with any artificial stoma. However, none of the technical modifications tried has proved reliable in reducing the incidence of parastomal herniation. The only clear-cut indications for repair are ileus and incarceration or serious problems with the colostomy bags. There are three basic methods of repair: fascial closure, stoma relocation and augmentation of the abdominal wall by nonabsorbable meshes, and any of the three can be combined in many ways. The first two techniques each have a recurrence rate of 40%-80%, and neither can therefore any longer be recommended for use in isolation. Only with the last technique of abdominal wall reinforcement it is possible to achieve a recurrence rate of under 20%. The best type of mesh and the optimal implantation technique are still under discussion.