A device for characterising the mechanical properties of the plantar soft tissue of the foot

Parker, DJ; Cooper, G; Pearson, S; Crofts, GS; Howard, D; Busby, P; Nester, CJ

Abstract

The plantar soft tissue is a highly functional viscoelastic structure involved in transferring load to the human body during walking. A Soft Tissue Response Imaging Device was developed to apply a vertical compression to the plantar soft tissue whilst measuring the mechanical response via a combined load cell and ultrasound imaging arrangement. Accuracy of motion compared to input profiles; validation of the response measured for standard materials in compression; variability of force and displacement measures for consecutive compressive cycles; and implementation in vivo with five healthy participants. Static displacement displayed average error of 0.04 mm (range of 15 mm), and static load displayed average error of 0.15 N (range of 250 N). Validation tests showed acceptable agreement compared to a Houndsfield tensometer for both displacement (CMC > 0.99 RMSE > 0.18 mm) and load (CMC > 0.95 RMSE < 4.86 N). Device motion was highly repeatable for bench-top tests (ICC = 0.99) and participant trials (CMC = 1.00). Soft tissue response was found repeatable for intra (CMC > 0.98) and inter trials (CMC > 0.70). The device has been shown to be capable of implementing complex loading patterns similar to gait, and of capturing the compressive response of the plantar soft tissue for a range of loading conditions in vivo.

Citation

Parker, D., Cooper, G., Pearson, S., Crofts, G., Howard, D., Busby, P., & Nester, C. (2015). A device for characterising the mechanical properties of the plantar soft tissue of the foot. Medical Engineering and Physics, 37(11), 1098-1104. https://doi.org/10.1016/j.medengphy.2015.08.008

• Journal Article Type: Article
• Acceptance Date: Aug 12, 2015
• Online Publication Date: Sep 4, 2015
• Publication Date: Nov 1, 2015
• Deposit Date: Dec 9, 2015
• Publicly Available Date: Apr 5, 2016
• Journal: Medical Engineering & Physics
• Print ISSN: 1350-4533
• Publisher: Elsevier
• Volume: 37
• Issue: 11
• Pages: 1098-1104
• DOI: https://doi.org/10.1016/j.medengphy.2015.08.008
• Publisher URL: http://dx.doi.org/10.1016/j.medengphy.2015.08.008
• Related Public URLs: http://www.jfootankleres.com/