Abstract
Two single-incision mini-slings used for treating urinary incontinence in women are compared with respect to the stresses they produce in their surrounding tissue. In an earlier paper we experimentally observed that these implants produce considerably different stress distributions in a muscle tissue equivalent. Here we perform 2D finite element analyses to compare the shear stresses and normal stresses in the tissue equivalent for the two meshes and to investigate their failure behavior. The results clearly show that the Gynecare TVT fails for increasing loads in a zipper-like manner because it gradually debonds from the surrounding tissue. Contrary to that, the tissue at the ends of the DynaMesh-SIS direct may rupture but only at higher loads. The simulation results are in good agreement with the experimental observations thus the computational model helps to interpret the experimental results and provides a tool for qualitative evaluation of mesh implants.
Acknowledgments
The experiments have been supported by the Federal Ministry of Economics and Technology (BMWi) through the ZIM cooperative project “Einstellbares alloplastisches Schlingensystem zur minimal-invasiven Therapie der Belastungsinkontinenz bei Frauen”. The FEM analyses have been supported by the Federal Ministry of Education and Research (BMBF) through the FHProfUnt project “Optimierung des Systems Netzimplantat-Beckenboden zur therapeutischen Gewebeverstärkung nach der Integraltheorie” (BINGO).
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