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

Objective: Every person is required to walk and stand for long periods of time during daily activities, especially at work, as a result of which ground reaction force to the parts and joints is very high, and these forces sometimes reach several times the body weight in the foot and the ankle foot can have devastating effects. Various studies have suggested different methods and factors for reducing ground reaction force when walking. The purpose of this study is to determine the different causes of factors and methods affecting ground reaction force according to existing research. Materials & Methods: This review study was conducted by searching the databases (ISI) web of science, Embase, pubmed, proquest from 1995 to 2019. Keywords ground reaction force, foot orthosis ,walking, long term standing and Impact force were selected. After reviewing the abstract and the title of each study, the authors considered the criteria for selecting the article, such as whether the title of the article answers the researcherchr('39')s questions or not. The control level of each article was rated as randomized control trial, prospective controlled trial (cohort), case-control, pre / post, observational consensus clinical and based on the main design of 5 to 1, respectively. The quality of the articles was evaluated and scored using the Down and Black tool. Results: From 82 articles obtained, 21 final articles were selected for analysis based on the criteria. Reporting scores, external validity, internal 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 force of the ground reaction, 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.