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In Vitro Culture of Epithelial Cells from Different Anatomical Regions of the Human Amniotic Membrane
Published on: November 28, 2019
On the deformation behavior of human amnion
Wilfried Buerzle1, Edoardo Mazza
1Department of Mechanical and Process Engineering, Swiss Federal Institute of Technology, Zurich, Switzerland. buerzle@imes.mavt.ethz.ch
Journal of Biomechanics
|June 20, 2013
Summary
Human amnion exhibits unique mechanical properties, including an exceptionally high Poisson's ratio, crucial for understanding fetal membrane behavior during pregnancy and surgery. This research models its deformation for improved surgical outcomes.
Area of Science:
- Biomedical Engineering
- Materials Science
- Obstetrics
Background:
- Renewed interest in fetal membrane mechanics stems from iatrogenic preterm rupture risks in minimally invasive fetal surgery.
- Understanding the amnion's mechanical behavior is vital for enhancing surgical safety and effectiveness.
Purpose of the Study:
- To characterize and model the deformation behavior of the human amnion layer.
- To establish constitutive equations for predicting amnion's mechanical response.
Main Methods:
- Uniaxial tension tests performed on human amnion samples post-cesarean section.
- Digital image correlation used to analyze the deformation field.
- Development of constitutive models based on microstructural interpretation.
Main Results:
- Human amnion displays highly reproducible kinematic response.
- An incremental Poisson's ratio up to 8 was recorded, exceeding known biological and synthetic materials.
- Collagen fiber rotation, stretching, and buckling explain the unique deformability.
Conclusions:
- The developed model accurately predicts the mechanical response of human amnion.
- Collagen fiber architecture is key to amnion's exceptional deformability and toughness.
- Insights gained can inform strategies to prevent preterm rupture and improve fetal surgery.
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