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International Urogynecology Journal

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Open Access 01-07-2020 | Original Article

Persistent occiput posterior position and stress distribution in levator ani muscle during vaginal delivery computed by a finite element model

Authors: Linda Havelková, Ladislav Krofta, Petra Kochová, Václav Liška, Vladimír Kališ, Jaroslav Feyereisl

Published in: International Urogynecology Journal | Issue 7/2020

Abstract

Introduction and hypothesis

Objective of this study was to develop an MRI-based finite element model and simulate a childbirth considering the fetal head position in a persistent occiput posterior position.

Methods

The model involves the pelvis, fetal head and soft tissues including the levator ani and obturator muscles simulated by the hyperelastic nonlinear Ogden material model. The uniaxial test was measured using pig samples of the levator to determine the material constants. Vaginal deliveries considering two positions of the fetal head were simulated: persistent occiput posterior position and uncomplicated occiput anterior position. The von Mises stress distribution was analyzed.

Results

The material constants of the hyperelastic Ogden model were measured for the samples of pig levator ani. The mean values of Ogden parameters were calculated as: μ1 = 8.2 ± 8.9 GPa; μ2 = 21.6 ± 17.3 GPa; α1 = 0.1803 ± 0.1299; α2 = 15.112 ± 3.1704. The results show the significant increase of the von Mises stress in the levator muscle for the case of a persistent occiput posterior position. For the optimal head position, the maximum stress was found in the anteromedial levator portion at station +8 (mean: 44.53 MPa). For the persistent occiput posterior position, the maximum was detected in the distal posteromedial levator portion at station +6 (mean: 120.28 MPa).

Conclusions

The fetal head position during vaginal delivery significantly affects the stress distribution in the levator muscle. Considering the persistent occiput posterior position, the stress increases evenly 3.6 times compared with the optimal head position.

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Title: Persistent occiput posterior position and stress distribution in levator ani muscle during vaginal delivery computed by a finite element model
Authors: Linda Havelková
Ladislav Krofta
Petra Kochová
Václav Liška
Vladimír Kališ
Jaroslav Feyereisl
Publication date: 01-07-2020
Publisher: Springer International Publishing
Published in: International Urogynecology Journal / Issue 7/2020
Print ISSN: 0937-3462
Electronic ISSN: 1433-3023
DOI: https://doi.org/10.1007/s00192-019-03997-8

Keynote webinar | Spotlight on medication adherence

Springer Medicine

Persistent occiput posterior position and stress distribution in levator ani muscle during vaginal delivery computed by a finite element model

Abstract

Introduction and hypothesis

Methods

Results

Conclusions

Keynote webinar | Spotlight on medication adherence

Springer Medicine

Abstract

Introduction and hypothesis

Methods

Results

Conclusions

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