Page 145 - Prevention and Treatment of Incisional Hernia- New Techniques and Materials

Introduction
Incisional hernia (IH) is one the most frequent postoperative complications after abdominal surgery (1-3). The reason for IH formation can be attributed to patient-related factors, such as high body mass index (BMI), smoking, corticosteroid use, abdominal aortic aneurysm (AAA), or other connective tissue disorders(4-8). Otherwise, IH formation can also be in uenced by factors related to the surgeon or the surgical procedure, such as suture technique, surgical site infections and fascial dehiscence(9-11). More recently, we found that parastomal hernia appeared to be a risk factor for IH(12). Patients with a parastomal hernia had a 7.2 higher Odds Ratio for IH formation(12). In addition, 55% of all IH developed at the level of the colostomy. We hypothesized that the biomechanical forces in the abdominal wall would change after colostomy creation, inducing a greater rate of IH. One hypothesis was that the midline incision would shift to the right (or contralateral side) due to reduced restraining forces at the site of the colostomy. A midline shift would increase the tensile force on a part of the sutures and this shift would then cause separation of the wound edges, which is a major predictor of IH (13, 14). In addition, we hypothesized that would induce atrophy of the abdominal rectus muscle (ARM) due to transection or injury to the intercostal or subcostal nerves innervating the ARM (15). A radiologic anatomic study was performed to determine if colostomy creation induces a midline shift and ARM atrophy.
Methods
Inclusion and exclusion criteria
Patients were selected from the PACIFIC cohort, a multicenter study which was conducted at the Erasmus University Medical Center, Rotterdam, the Netherlands and the Albert Schweitzer Hospital, Dordrecht, the Netherlands(12). Patients were included in this cohort if they had undergone a left-sided, end-colostomy during an open Hartmann Procedure or abdominoperineal resection between 2004 and 2011. Patients were selected for this study if a CT had been taken postoperatively. If available, pre-operative CT-scans were also collected for case- control analyses. Patients were excluded if the time between operation and the postoperative CT was less than 1 month, if a patient had a transposition of the
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Abdominal wall changes and IH
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