The prediction of incisional hernias by radio-opaque markers

On the hypothesis that incisional defects occur soon after operation but the resulting hernia may not be diagnosed until months or years later, we attached three to five pairs of stainless steel haemostatic clips to the cut edges of the anterior aponeurosis during the closure of 59 major laparotomy incisions and X-rayed the abdomen one month later. Three patients were withdrawn and the remaining 56 were examined with special reference to incisional herniation at their six-month follow-up visit. The senior author subsequently arranged a series of extra clinics for surviving patients up to three years later (median 30 months after operation). He had no knowledge of the results of the abdominal X-rays when assessing whether or not the patient had a hernia. Six patients were found to have incisional hernias, and correlation with the measurements on the one-month X-rays showed separation of pairs of clips ranging from 12-70 mm (median 40). Three of the six hernias were discovered within seven months, the remaining three at 13, 28 and 29 months. In contrast none of the 50 patients without incisional hernias had more than 9 mm of separation of any pair of clips on the one-month X-ray. We conclude that the origins of incisional hernias can be traced back to events during the first month after operation and that they are not the result of later weakening of a well-healed laparotomy wound.