The Effect of Customized 3D Printed Insoles on Physical Activity Level, Balance, and Physical Performance in Patients with Pes Planus: A Randomized, Placebo Controlled, DoubleBlinded Study

Objective: This study aimed to investigate the effects of individually designed insoles on physical activity level, balance, and functional performance in patients with pes planus. Materials and Methods: 38 participants were divided into 2 groups as 3D printed (n=20) and placebo (n=18). In the 3D printed group, medial longitudinal arch support, medial wedge of the foot, medial heel wedge, and transverse arch support were given to the insoles according to the needs of the participants. The placebo group received placebo insoles. Muscle strength, range of motion, static and dynamic balance, physical and physical activity levels were measured at baseline, and eight weeks later (clinicaltrials.gov ID: NCT05306886). Results: Muscle strengths of the plantar flexion (p=0.030) and eversion increased after the use of insoles in the 3D printed and placebo groups (p=0.020). There was no change in static balance in both groups (p=0.386), but there were significant improvements in dynamic balance in 3D printed groups (p=0.019). Gait speed improved in both 3D printed (p=0.001) and placebo groups (p=0.015). There was no significant difference in the explosive power between the groups (p=0.272). The shuttle run test improved significantly in the placebo group (p=0.015), but no significant change was observed in the 3D printed group (p=0.886). While the physical activity levels in the placebo group showed a significant improvement (p=0.017), the physical activity level decreased in the 3D printed group (p=0.489). Conclusions: In this study, it was found that the use of personalized insoles is effective in improving physical activity, balance, and performance, while placebo insoles were found to be more effective in increasing muscle strength and explosive muscle strength.