Volume 5 Supplement 1

3rd Congress of the International Foot and Ankle Biomechanics Community

Open Access

Anatomical plantar pressure masking and foot models: potential for integration with marker position systems

Journal of Foot and Ankle Research20125(Suppl 1):O29

DOI: 10.1186/1757-1146-5-S1-O29

Published: 10 April 2012

Background

Investigation of local foot loading using baropodometry is highly relevant in both research and clinical settings. In order to reliably associate local pressure data with foot function and structure, anatomy-based masking of footprints is recommended, especially when foot anatomy or footprints are significantly altered. Previous studies combining baropodometry with stereophotogrammetry have shown the value of this methodology in specific, prototype-based situations [1, 2]. This study thoroughly investigates the potential of this method.

Materials and methods

A set of regular footprints from young healthy volunteers was acquired under controlled conditions by using commercial 3D kinematic tracking systems and pressure mats. The Oxford kinematic foot model [3] was used for medio-lateral regionalisation of the foot – clinically relevant for clubfoot and flatfoot –, the Rizzoli model [4] for longitudinal regionalisation, to clearly distinguish metatarsal from toe or midfoot loading.

Results

100 footprints from 20 volunteers have been processed so far for the Oxford model (processing still ongoing for the Rizzoli model). For medial and lateral hindfoot, and for medial and lateral forefoot, differences from a proper geometry-based masking were 3.4-3.9% (vertical force), 0.7-2.7% (peak pressure), 1.6-4.5% (mean pressure), 2.1-3.8% (area); midfoot differences rose to 5.2% and 9.7% for peak and mean pressure. However, none of the differences were statistically significant.

Conclusions

With a correct marker positioning, and an appropriate calibrated pressure mat (accuracy error <5%, spatial resolution 4sens/cm2), the method was validated with respect to a proper geometrical selection (differences <5%). The effect and clinical relevance of lower spatial resolution, marker positioning errors and use of clusters instead of skin markers, is also being investigated.
Figure 1

Projections of marker set onto the footprint obtained by applying the Oxford model (left) and the Rizzoli model (right).

Authors’ Affiliations

(1)
Dept. of Technology and Health, Italian National Institute of Health (ISS)
(2)
Nuffield Orthopaedic Centre
(3)
Istituto Ortopedico Rizzoli

References

  1. Stebbins JA, Harrington ME, Giacomozzi C, Thompson N, Zavatsky A, Theologis TN: Assessment of sub-division of plantar pressure measurement in children. Gait Posture. 2005, 22: 372-376. 10.1016/j.gaitpost.2004.10.004.View ArticlePubMedGoogle Scholar
  2. Giacomozzi C, Benedetti MG, Leardini A, Macellari V, Giannini S: Gait analysis with an integrated system for functional assessment of talocalcaneal coalition. J Am Podiatr Med Assoc. 2006, 96: 107-115.View ArticlePubMedGoogle Scholar
  3. Stebbins J, Harrington M, Thompson N, Zavatsky A, Theologis T: Repeatability of a model for measuring multi-segment foot kinematics in children. Gait Posture. 2006, 23: 401-410. 10.1016/j.gaitpost.2005.03.002.View ArticlePubMedGoogle Scholar
  4. Leardini A, Benedetti MG, Berti L, Bettinelli Nativo DR, Giannini S: Rear-foot, mid-foot and fore-foot motion during the stance phase of gait. Gait Posture. 2007, 25: 453-462. 10.1016/j.gaitpost.2006.05.017.View ArticlePubMedGoogle Scholar

Copyright

© Giacomozzi et al; licensee BioMed Central Ltd. 2012

This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Advertisement