Effect of mesh anchoring technique in uterine prolapse repair surgery: A finite element analysis

The female pelvic cavity involves muscles, ligaments, endopelvic fasciae and multiple organs where different pathologies may occur, namely the pelvic organ prolapse (POP). The synthetic implants are used for the reconstructive surgery of POP, but severe complications associated with their use have been reported, mainly related to their mechanical properties (e.g., implant stiffness) and microstructure. In this study, we mimicked a transvaginal reconstructive surgery to repair the apical ligaments (uterosacral ligaments (USLs) and cardinal ligaments (CLs)), by modeling, their impairment (90% and 50%) and/or total rupture. The implants to reinforce/replace these ligaments were built based on literature specifications and their mechanical properties were obtained through uniaxial tensile tests. The main aim of this study was to simulate the effect of mesh anchoring technique (simple stich and continuous stitch), and compare the displacement magnitude of the pelvic tissues, during Valsalva maneuver. The absence/presence of the synthetic implant was simulated when total rupture of the CLs and USLs occurs, causing a variation of the vaginal displacement (9% for the CLs and 27% for the USLs). Additionally, the simulations showed that there was a variation of the supero-inferior displacement of the vaginal wall between different anchoring techniques (simple stich and continuous stitch) being approximately of 10% for the simulation USLs and CLs implant. The computational simulation was able to mimic the biomechanical behavior of the USLs and CLs, in response to different anchoring techniques, which can be help improving the outcomes of the prolapse surgery.