The Effect of Foot Orthosis on the Vertical Component of the Ground Reaction Force While Walking: A Review Study

Abstract

Objective Everyone is required to walk and stand for long time in daily activities, especially in the workplace. As a result, the Ground Reaction Force (GRF) on the components and joints is so great that they sometimes reach several times the weight of the body. These forces can have devastating effects on the feet and ankles. Various studies have suggested different methods and factors for reducing the GRF while walking. The purpose of this study was to identify the different causes of factors and methods affecting the GRF according to the current study. Materials & Methods This review study was conducted by searching the databases of ProQuest, PabMed, Web of Science, and MBS from 1995 to 2019. The keywords included 'Ground Reaction Force', foot orthosis', 'walking', 'long term standing impact force'. After reviewing the abstract and title of each study by the authors, the criteria for selecting the article were considered. At the control level of each article, based on the main design of the search, from 1 to 5 were scored as randomized control trial, prospective controlled trial (Cohort), case-control, pre/post, observational clinical consensus, respectively. The quality of the articles was evaluated and scored using the Down and Black tool. Results Out of 82 articles, 21 articles were selected for analysis based on the criteria. Reporting scores, external validity, and internal validity varied between 4-8, 3-1, 5-2, 6-3, 7-4, respectively. From the studies performed on the molding insoles and the change in the loading rate of the maximum vertical GRF, there is a contradiction in proving it. Investigating the effect of foot orthoses in terms of material may lead to a further reduction in plantar. Conclusion Determining the effect of different components on GRF in the sole of the foot will help us better understand the factors involved in quality of life. The four domains of gender, post, material, and molding had different effects. Due to the lack of articles related to the study of the effect of gender and the creation of posts in the insole on the GRF can not be decisive.