Page 13 - Prevention and Treatment of Incisional Hernia- New Techniques and Materials

Introduction
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Ever since human beings have been walking in an erect position, abdominal wall hernias have likely been a problem. A hernia is a protrusion of abdominal content (preperitoneal fat, omentum, or abdominal organs) through an abdominal wall defect. Hernias usually develop in anatomically congenitally weak locations (e.g. inguinal, umbilical, and hiatal hernias) or as a result of prior surgery (incisional, parastomal, and trocar site hernias). After the discovery and introduction of asepsis and general anesthesia in the 19th century, there was a signi cant increase in the number of surgical interventions, and in the likelihood of surviving intra-abdominal surgery. As abdominal surgery became more common, the incidence of incisional hernia (IH) increased. In the present day, IH remains a common complication of surgery, and represents a large proportion of all ventral abdominal wall hernias; therefore, the subject of this thesis is IH. IH develops when the fascial tissue fails to heal at the incision site of a prior laparotomy. IHs are symptomatic in the vast majority of patients and associated with pain and discomfort, often resulting in a decreased quality of life and perception of body image(1). Additionally, incarceration and strangulation of abdominal contents can occur, for which emergency surgery is indicated, with associated morbidity and mortality(2). Furthermore, IHs are costly to treat(1, 3, 4) and recurrences do occur(5).
In decreasing order of incidence, IH can be diagnosed after upper midline incisions, lower midline incisions, transverse incisions, and subcostal incisions. Although midline incision is the type most associated with a high incidence of IH, it is still the incision most frequently used by abdominal surgeons. The midline incision provides surgeons with a rapid and wide access to the abdominal cavity, with minimal damage to the nerves, vascular structures, and muscles of the abdominal wall. IHs are also found to occur after paramedian, McBurney, Pfannenstiel, and ank incisions. Approximately 10- 25% of all patients will develop IH after midline laparotomy(6-9). This incidence rises to 35% in patients with an aneurysm of the abdominal aorta(10-12); and incidences as high as 69% have been reported in high-risk patients after prospective long-term follow-up(13). During laparotomy, the creation of a stoma through the abdominal wall is necessary in approximately 25% of patients. A parastomal hernia (PSH) – a kind of IH – is a frequent complication following stoma creation, with a reported incidence of up to 48%(14, 15).
Introduction and outline of the thesis
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