A new MR-compatible loading device to study in vivo muscle damage development in rats due to compressive loading

Stekelenburg, A.; Oomens, C.W.J.; Strijkers, G.J.; de Graaf, L.; Bader, D.L.; Nicolay, K.

doi:10.1016/j.medengphy.2005.07.005

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Volume 28, Issue 4 , Pages 331-338, May 2006

A new MR-compatible loading device to study in vivo muscle damage development in rats due to compressive loading

A. Stekelenburg
- Department of Materials Technology, Department of Biomedical Engineering, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands
- Corresponding author. Tel.: +31 40 2473075; fax: +31 40 2447355.
C.W.J. Oomens
- Department of Materials Technology, Department of Biomedical Engineering, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands
G.J. Strijkers
- Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands
L. de Graaf
- Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands
D.L. Bader
- Department of Materials Technology, Department of Biomedical Engineering, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands
- Department of Engineering and IRC in Biomedical Materials, Queen Mary, University of London, UK
K. Nicolay
- Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands

Received 10 March 2005; received in revised form 9 June 2005; accepted 8 July 2005. published online 23 August 2005.

Abstract

To study the aetiology of pressure ulcers an MR-compatible loading device was developed. Magnetic resonance imaging provides the possibility of non-invasive evaluation of muscle tissue after compressive loading. Pressure was applied to the tibialis anterior region of rats by means of an indenter. The developed MR-compatible loading device allowed high quality consecutive MR measurements for up to 6h. Tissue was evaluated both during and after loading. Two loading protocols were used; a large indentation of 4.5mm (mean pressure 150kPa) was applied for 2h and a small indentation of 2.9mm (mean pressure 50kPa) was applied for 4h. T2-weighted MR images after the large indentation showed an immediate increase in signal intensity, associated with damage, following load removal. After 20h the signal intensity remained higher in the affected regions. Afterwards the tissue was perfusion fixated for histological examination. Histological evaluation revealed an inflammatory response and severe muscle necrosis. No signal increase was observed after small indentation. With this new set-up, the different factors that may play a role in the onset of muscle damage can be studied, what we believe will lead to a better understanding of the contributing factors to pressure ulcer development.