The Effect of Thermoplastic Insoles on Center of Pressure Parameters in Individuals with Flatfoot Deformity - Journal of Sport Biomechanics

Abstract

Objective Flatfoot deformity is one of the most common musculoskeletal disorders that can impair postural stability and balance by altering center of pressure (COP) characteristics. Given the importance of non-invasive approaches, the present study aimed to investigate the effect of thermoplastic insoles on COP parameters in individuals with flatfoot deformity. Methods In this quasi-experimental study, 14 eligible participants were randomly assigned to either the intervention group (thermoplastic insole, n=7) or the control group (n=7). Static and dynamic COP data were recorded using a foot-scan system. Following a 45-day intervention period, data collection was repeated. Statistical analyses were performed using paired t-tests and univariate analysis of covariance (ANCOVA) at a significance level of 0.05. Results The findings demonstrated that the use of thermoplastic insoles significantly improved COP parameters in both the mediolateral (ML) and anteroposterior (AP) directions and significantly reduced the Confidence Ellipse Area (CEA) in the intervention group (P<0.05). In contrast, no significant changes were observed in the control group (P>0.05). Conclusion Due to their elastic properties and effective mechanical support, thermoplastic insoles may represent an effective biomechanical intervention for enhancing postural stability and reducing center of pressure (COP) oscillations in individuals with flatfoot deformity