Finite Element Studies of the Deformation of the Pelvic Floor

Martins, J. A. C.; Pato, Matilde; Pires, E. B.; Jorge, R.M. Natal; Parente, Marco; Mascarenhas, Teresa

doi:10.1196/annals.1389.019

Cited by 67 publications

(64 citation statements)

References 25 publications

(67 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Several computer models of vaginal birth have been developed [4, 9], most of which are focused on the second stage of labor, starting from full dilatation of the cervix until birth of the fetus [10]. In this study cardinal movements of labor are often neglected.…”

Section: Introductionmentioning

confidence: 99%

Finite element model focused on stress distribution in the levator ani muscle during vaginal delivery

et al. 2016

View full text Add to dashboard Cite

Introduction and hypothesisDuring vaginal delivery, the levator ani muscle (LAM) undergoes severe deformation. This stress can lead to stretch-related LAM injuries. The objective of this study was to develop a sophisticated MRI-based model to simulate changes in the LAM during vaginal delivery.MethodsA 3D finite element model of the female pelvic floor and fetal head was developed. The model geometry was based on MRI data from a nulliparous woman and 1-day-old neonate. Material parameters were estimated using uniaxial test data from the literature and by least-square minimization method. The boundary conditions reflected all anatomical constraints and supports. A simulation of vaginal delivery with regard to the cardinal movements of labor was then performed.ResultsThe mean stress values in the iliococcygeus portion of the LAM during fetal head extension were 4.91–7.93 MPa. The highest stress values were induced in the pubovisceral and puborectal LAM portions (mean 27.46 MPa) at the outset of fetal head extension. The last LAM subdivision engaged in the changes in stress was the posteromedial section of the puborectal muscle. The mean stress values were 16.89 MPa at the end of fetal head extension. The LAM was elongated by nearly 2.5 times from its initial resting position.ConclusionsThe cardinal movements of labor significantly affect the subsequent heterogeneous stress distribution in the LAM. The absolute stress values were highest in portions of the muscle that arise from the pubic bone. These areas are at the highest risk for muscle injuries with long-term complications.

show abstract

Section: Introductionmentioning

confidence: 99%

Finite element model focused on stress distribution in the levator ani muscle during vaginal delivery

et al. 2016

View full text Add to dashboard Cite

show abstract

“…Although these examinations have been used to assess the anatomy of the female PF in cadavers (Janda et al 2003) and living women (Bourcier et al 2004), the clinical conclusions obtained from these geometric models are still inconclusive. On this work, an alternative approach is used, based on the finite element method (FEM; Martins et al 2007).…”

Section: Introductionmentioning

confidence: 99%

An approach on determining the displacements of the pelvic floor during voluntary contraction using numerical simulation and MRI

Saleme

Parente

Jorge

et al. 2011

Computer Methods in Biomechanics and Biomedical Engineering

Self Cite

View full text Add to dashboard Cite

The present study was conducted in order to establish a methodology based on the finite element method to simulate the contraction of the pelvic floor (PF) muscles. In the generated finite element model, a downward pressure of 90 cm H(2)O was applied, while actively contracting the PF muscles with different degrees of muscular activation (10, 50 and 100%). The finite element methodology of the active contraction behaviour proposed in this study is adequate to simulate PF muscle contraction with different degrees of muscular activation. In this case, in particular, for an activation of 100%, the numerical model was able to displace the pubovisceral muscle in a range of values very similar to the displacement found in the magnetic resonance imaging data. In the analysed case study, it would be possible to conclude that an intensity contraction of 50% would be necessary to produce enough stiffness to avoid possible urine loss.

show abstract

“…This resting tone is absent in previous cadaver studies. 20,21 Therefore, our model provides a more realistic description of the pelvic floor geometry.…”

Section: Resultsmentioning

confidence: 99%

Modelling the pelvic floor for investigating difficulties during childbirth

Kruger

Chung

et al. 2008

SPIE Proceedings

View full text Add to dashboard Cite

Research has suggested that athletes involved in high-intensity sports for sustained periods have a higher probability of experiencing prolonged second stage of labour compared to non-athletes. The mechanism responsible for this complication is unknown but may depend on the relative size or tone of the pelvic floor muscles. Prolonged training can result in enlargement and stiffening of these muscles, providing increased resistance as the fetal head descends through the birth canal during a vaginal birth. On the other hand, recent studies have suggested an association between increased muscle bulk in athletes and higher distensibility. This project aims to use mathematical modelling to study the relationship between the size and tone of the pelvic floor muscles and the level of difficulty during childbirth. We obtained sets of magnetic resonance (MR) images of the pelvic floor region for a female athlete and a female non-athlete. Thirteen components of the pelvic floor were segmented and used to generate finite element (FE) models. The fetal head data was obtained by laser scanning a skull replica and a FE model was fitted to these data. We used contact mechanics to simulate the motion of the fetal head moving through the pelvic floor, constructed from the non-athlete data. A maximum stretch ratio of 3.2 was induced in the muscle at the left lateral attachment point to the pubis. We plan to further improve our modelling framework to include active muscle contraction and fetal head rotations in order to address the hypotheses that there is a correlation between the level of difficulty and the size or tone of the pelvic floor muscles.

show abstract

Finite Element Studies of the Deformation of the Pelvic Floor

Cited by 67 publications

References 25 publications

Finite element model focused on stress distribution in the levator ani muscle during vaginal delivery

Finite element model focused on stress distribution in the levator ani muscle during vaginal delivery

An approach on determining the displacements of the pelvic floor during voluntary contraction using numerical simulation and MRI

Modelling the pelvic floor for investigating difficulties during childbirth

Contact Info

Product

Resources

About