You are looking at 1 - 2 of 2 items for
- Author or Editor: Jeanna M. Fascione x
- Refine by access: All Content x
The use of foot measurements to classify morphology and interpret foot function remains one of the focal concepts of lower-extremity biomechanics. However, only 27% to 55% of midfoot variance in foot pressures has been determined in the most comprehensive models. We investigated whether dynamic walking footprint measurements are associated with inter-individual foot loading variability.
Thirty individuals (15 men and 15 women; mean ± SD age, 27.17 ± 2.21 years) walked at a self-selected speed over an electronic pedography platform using the midgait technique. Kinetic variables (contact time, peak pressure, pressure-time integral, and force-time integral) were collected for six masked regions. Footprints were digitized for area and linear boundaries using digital photo planimetry software. Six footprint measurements were determined: contact area, footprint index, arch index, truncated arch index, Chippaux-Smirak index, and Staheli index. Linear regression analysis with a Bonferroni adjustment was performed to determine the association between the footprint measurements and each of the kinetic variables.
The findings demonstrate that a relationship exists between increased midfoot contact and increased kinetic values in respective locations. Many of these variables produced large effect sizes while describing 38% to 71% of the common variance of select plantar kinetic variables in the medial midfoot region. In addition, larger footprints were associated with larger kinetic values at the medial heel region and both masked forefoot regions.
Dynamic footprint measurements are associated with dynamic plantar loading kinetics, with emphasis on the midfoot region.
Dynamic Footprint Measurement Collection Technique and Intrarater Reliability
Ink Mat, Paper Pedography, and Electronic Pedography
Identifying the variability of footprint measurement collection techniques and the reliability of footprint measurements would assist with appropriate clinical foot posture appraisal. We sought to identify relationships between these measures in a healthy population.
On 30 healthy participants, midgait dynamic footprint measurements were collected using an ink mat, paper pedography, and electronic pedography. The footprints were then digitized, and the following footprint indices were calculated with photo digital planimetry software: footprint index, arch index, truncated arch index, Chippaux-Smirak Index, and Staheli Index. Differences between techniques were identified with repeated-measures analysis of variance with post hoc test of Scheffe. In addition, to assess practical similarities between the different methods, intraclass correlation coefficients (ICCs) were calculated. To assess intrarater reliability, footprint indices were calculated twice on 10 randomly selected ink mat footprint measurements, and the ICC was calculated.
Dynamic footprint measurements collected with an ink mat significantly differed from those collected with paper pedography (ICC, 0.85–0.96) and electronic pedography (ICC, 0.29–0.79), regardless of the practical similarities noted with ICC values (P = .00). Intrarater reliability for dynamic ink mat footprint measurements was high for the footprint index, arch index, truncated arch index, Chippaux-Smirak Index, and Staheli Index (ICC, 0.74–0.99).
Footprint measurements collected with various techniques demonstrate differences. Interchangeable use of exact values without adjustment is not advised. Intrarater reliability of a single method (ink mat) was found to be high. (J Am Podiatr Med Assoc 102(2): 130–138, 2012)