A combined experimental and numerical approach to evaluate hernia mesh biomechanical stability in situ

A ventral hernia involves tissue protrusion through the abdominal wall (AW). It is a common surgical issue with high recurrence rates. Primary stability of hernia meshes is essential to guarantee mesh integration, yet existing meshes often fail to match the AW's complex biomechanics. This study proposes a novel method aiming at understanding post-operative mesh-AW interactions. Three fresh frozen human specimens underwent an open Rives-Stoppa implantation of a synthetic hernia mesh coated with metallic micro-beads. Additional beads were placed into the AW muscle tissue. CT scans were conducted at increasing levels of intra-abdominal pressure to reproduce forced breathing. Beads 3D coordinates were exported from the CT-scans and motion and strain of both the hernia mesh and the AW were calculated. At 30 mmHg, the mesh-muscle motion (or sliding) was 2.3 ± 1.3 mm. Muscle exhibited significantly higher strains (12.9 ± 4.7 %) than the hernia mesh (4.7 ± 1.1 %), most likely due to difference in material properties between the mesh and the AW. A repeatability study was carried out to build confidence in the proposed method. This protocol can bring insights of the hernia mesh use-conditions to improve hernia mesh design requirements and develop safer implants to reduce hernia recurrence.