Evaluation of Strains on Levator Ani Muscle: Damage Induced During Delivery for a Prediction of Patient Risks

Since childbirth presents a significant risk factor for pathology occurrence of the pelvic floor, analysis of the phenomena involved during a vaginal delivery is a major issue in obstetrics and gynecology researches. Computational biomechanics tool dedicated to the delivery could help to understand the causes of injuries and predict the perineal lesion. From MRI images of four women at different terms of pregnancy, a parametric FE model is generated and allows to analyze the potential damage areas during childbirth, related to strain rate of anatomical structures. The influence of the geometry of levator ani muscle, head size, terms, and cephalic presentations are investigated. The geometrical refinement of anatomical structures influences the strain levels and helps to localized more precisely the most injured areas. Posterior cephalic presentation presents higher injury risk than the anterior one. Maternal geometry at different terms brings equivalent results contrary to the fetal head sizes that have an influence on the strain level and the potential damage induced. This multi-parametric investigation allows us to have a customizable and predictive tool evaluating the potential damages on the pelvis during delivery.

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