Page 135 - Prevention and Treatment of Incisional Hernia- New Techniques and Materials

Prevalence
During physical examination, out of the total of 150 patients, 56 IHs (37.3%) and 79 PSHs (52.7%) were diagnosed (Table 2). Both hernia types were present in the same patient in 45 cases (p < 0.001). In 87 patients, a CT-scan was available and an objective evaluation of hernia presence could be performed. The available CT scans had been requested as follow-up method related to the initial disease of the patient. The CT revealed 42 IHs (48.3%) and 46 PSHs (52.9%). Both were present in 31 of the CT scans (35.6%), which was also statistically signi cant (p < 0.001). Physical examination for the diagnosis of IH reached a sensitivity of 0.79 and a speci city of 0.96. For PSH a sensitivity of 0.87 was reached with a speci city of 0.95.
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Table 2. Physical examination and CT-scan examination.
Parastomal and incisional hernia
Physical examination (n=150) - IH
- PSH
- IH and PSH
CT-scan (n=87) - IH
- PSH
- IH and PSH
Prevalence
56 (37%) 79 (53%) 45 (30%)
42 (48%) 46 (53%) 31 (36%)
X2 p-value*
< 0.001
< 0.001
*Association is tested by means of Chi-Square testing.
Discussion
This study con rms our hypothesis that the presence of PSH represents a risk factor for the occurrence of IH. Patients who acquire a PSH had a seven times higher odds of developing an IH compared to patients without a PSH.
The prevalence of PSH in our study was 52.7%, which corresponds with existing literature and in our previous experience with colostomies (7). The incidence of PSH does not di er when open or laparoscopic colostomy creation are compared, suggesting that PSH is not a ected by midline incision or hernia (7, 19, 20). A number of potential theories explaining the high rate of PSH have been suggested in the literature. Increased abdominal pressure can exit through the opening in the abdominal wall possibly promoting PSH. According to Laplace’s law, the tangential forces working on the colostomy may enlarge the fascial opening and cause PSH (21). Additionally the creation of the colostomy opening is not a standardized procedure. An overly small
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