[Changes in abdominal wall mechanics after mesh implantation. Experimental changes in mesh stability].

The use of biomaterials for incisional hernia markedly reduces the recurrence rates. Disadvantages are high rates of local wound complications and restriction of mobility by the rigid "shell". The abdominal wall mobility after mesh implantation is analysed for eight different mesh materials. The initial textile testing reveals relevant differences in structure with marked asymmetry in the different directions. The materials are implanted as inlay in rats for 3, 7, 14, 21 and 90 days. The deformation of the abdominal wall following intraabdominal pressure of 0-70 mmHg (0-9.81 kPa) is documented by 3D-photogrammetry, the tensile strength by tearing of excised strips of mesh. Three commercial available materials and two laboratory modifications lead independently of their textile characteristics to a marked restriction of the rounded configuration of the abdominal wall. The tensile strength exceeds by far the physiologically necessary value of 16 N/cm. Three newly developed meshes made of multifilament polypropylene with reduced amounts of material (21% and 28% relative to Marlex) lead to no restriction of the abdominal wall configuration yet have uncompromised stability. It might be possible to reduce the rate of local wound complications by the use of these newly developed meshes.