Influence of casting method on effectiveness of foot orthoses using plantar pressure distribution: a preliminary study

Background: Existing techniques of taking foot impressions for producing foot orthoses are static, while walking is a dynamic process. Objectives: The aim of the study was to evaluate a newly developed dynamic casting method for foot orthoses in comparison with static casts. Study Design: Double-blind, randomized two-period cross-over trial. Methods: Twelve healthy volunteers (six women, six men) were randomly assigned within gender to two groups. The first group wore orthoses made from static casts for two weeks and then orthoses made from dynamic casts for two weeks, and the second group vice versa. The orthoses were worn during work in sports shoes. The outcome measure was coefficient of variation (CV, defined as standard deviation/mean) over seven measurement spots on each foot. Results: Foot orthoses produced by a dynamic casting system redistributed plantar pressure (reduced CV) more effectively in the first period on both feet. In the second period, carry-over effect and/or treatment wearing off was observed. Conclusion: The dynamic casting procedure is simple, low-cost and appears promising, but further research is needed to introduce it into clinical practice.