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bioRxiv · 10.1101/2020.09.02.274878

Reducing variance in a mouse defect healing model: Real-time Finite Element Analysis allows homogenization of tissue scale strains

Paul, G. R.·Wehrle, E.·Tourolle, D. C.·Kuhn, G. A.·Müller, R.
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Abstract

Mechanical loading allows both investigation into the mechano-regulation of fracture healing as well as interventions to improve fracture-healing outcomes such as delayed healing or non-unions. However, loading is seldom individualised or even targeted to an effective mechanical stimulus level within the bone tissue. In this study, we use micro-finite element analysis to demonstrate the result of using a constant loading assumption for all mouse femurs in a given group. We then contrast this with the application of an adaptive loading approach, denoted real time Finite Element (rtFE) adaptation, in which micro-computed tomography images provide the basis for micro-FE based simulations and the resulting strains are manipulated and targeted to a reference distribution. Using this approach, we demonstrate that individualised femoral loading leads to a better-specified strain distribution and lower variance in tissue mechanical stimulus across all mice, both longitudinally and cross-sectionally, while making sure that no overloading is occurring leading to refracture of the femur bones.

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Paul, G. R., Wehrle, E., Tourolle, D. C., Kuhn, G. A., Müller, R.. 2020-09-03. Reducing variance in a mouse defect healing model: Real-time Finite Element Analysis allows homogenization of tissue scale strains. https://doi.org/10.1101/2020.09.02.274878

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