MISMATCHES IN STIFFNESS BETWEEN THE VAGINA AND TRANSVAGINAL MESH LEAD TO STRESS CONCENTRATIONS NEAR AN ANTERIOR WALL INCISION

摘要

Trans-vaginal synthetic meshes have been commonly used to treat pelvic organ prolapse. Recently however, concerns related to the use of trans-vaginal mesh have arisen due to the high incidence of complications. The FDA received more than 3000 reports of complications related to these procedures between 2008 and 2010. Of the women who undergo this procedure, approximately 30% will require additional surgery within 4 years [1]. The most common complication reported was an erosion of the vaginal wall [2]. We hypothesize that mismatch between the mechanical properties of the vaginal tissue and the synthetic mesh lead to higher stresses in the vaginal tissue and subsequently to a higher risk of mesh erosion. To test this hypothesis we developed a model of a transvaginal procedure, the procedure most associated with complications. For this procedure, a full thickness incision is made in the anterior vaginal wall and a synthetic mesh is implanted. The mesh is attached on the abluminal surface of the anterior vagina with arms extending into specific connective tissues in the pelvis. An idealized computational model was constructed representing the vagina and mesh complex after mesh insertion. Mechanical stresses along the anterior vaginal wall incision were measured in response to a simulated increase in intra-abdominal pressure.