Testing meshes in a computer model of a laparoscopic ventral hernia repair

Background: The ideal mesh for hernia repair has yet to be found, in addition our knowledge of the biomechanics of the abdominal wall is poor. The aim of this study was to develop a computer model of a laparoscopic ventral hernia repair and to test different meshes in that model at various intra-abdominal pressures. Methods: Four meshes were tested in a computer model of a ventral hernia. Mechanical failure testing of each mesh was performed in both the longitudinal and transverse directions. A CT scan of a patient with a 5 cm umbilical hernia was used to generate a 3 dimensional model. Meshes were then applied to the model in an intraperitoneal onlay position with a 5 cm overlap. The model was then tested with intraabdominal pressures for standing, coughing and jumping with and without meshes. Results: Meshes varied significantly (p < 0.001) in both rupture force 14.8 (5.6) to 78 (5) n/cm and force in which they changed from elastic to plastic 1.6 (0.1) to 14.2 (0.2) n/cm. When applied to the computer model all significantly reduced the strain on the abdominal wall from 17.5% without mesh to less than 1% with mesh. All meshes prevented the hernia from bulging in the model. Conclusions: We have developed a computer model of laparoscopic ventral hernia repair based on engineering principles. This model demonstrated that meshes tested significantly reduced the strain on the abdominal wall. Further studies are required to refine this model in order to best simulate the biomechanics of the abdominal wall