Incisional hernias: when do they occur?

Incisional herniation remains a major problem for the general surgeon. Most published studies have followed up patients for 6-12 months after operation. In this study, 363 patients, known not to have an incisional hernia at 1 year, were reviewed between 2.5 and 5.5 years after operation. Twenty-one patients (5.8 per cent) were found to have developed incisional hernias. None of the causal factors previously implicated in the aetiology of incisional herniation (wound infection, male sex, obesity, age, postoperative chest infection or abdominal distension), was found to be associated with the development of these 'late hernias'.