A reproducible rat model for predicting incisional hernia recurrence: insights for clinical translation

Incisional hernias are common complications following abdominal surgeries. This study aimed to develop a reproducible murine model of complex incisional hernia to better understand this condition and evaluate new therapeutic strategies. Fourteen male Wistar rats underwent laparotomy to induce hernia formation. Intra-abdominal volume was measured. Hernia recurrence, tissue healing, and adhesion formation were evaluated through macroscopic and histopathological analysis, assessing fibrosis, angiogenesis, inflammation, and necrosis. All rats developed incisional hernias after laparotomy, with a 90% recurrence rate observed one week post-repair. The average hernia defect size was 10.30 mm ± 9.32 mm. A significant 25.63% reduction in intra-abdominal volume was recorded. Macroscopic examination revealed adhesions in 80% of the animals, with 60% classified as severe. Histopathological analysis showed fibrosis in all animals, with 70% displaying moderate to severe fibrosis, characterized by multifocal areas of recent fibrosis or signs of myofibroblastic differentiation. Inflammation, indicated by granulation tissue, was present in all animals. Necrosis was observed in 60% of the animals. Fibrosis affected 40% of the incision areas and 70% of the abdominal muscles. This animal model has proven versatile, reproducible, and reliable, making it suitable for investigating complex incisional hernias in translational studies.