Does Flexible Flatfoot Require Treatment?: Plantar Pressure Effects of Wearing Over-the-Counter Insoles when Walking on a Level Surface and Up and Down Stairs in Adults with Flexible Flatfoot.

Background: Orthotic insole is a popular physiotherapy for flatfoot. However, the effects and whether flexible flatfoot needs orthotic insole treatment are not clear, and how the plantar pressure changes while walking up and down stairs has not been studied. Therefore, this study observed the plantar pressures of different walking conditions to find the answers.

Methods: Fifteen adults with flexible flatfoot and 15 adults with normal foot were examined while walking on a level surface and while walking up and down 10- and 20-cm stairs before treatment. The maximum force and the arch index were acquired with a force plate system. Participants with flexible flatfoot were instructed to wear the orthotic insoles for 3 months, and plantar pressures were measured again after treatment. The repeated measure was performed to analyze the data.

Results: The maximum force and the arch index of flatfoot after treatment were significantly decreased under different walking conditions ( < .01). When walking down 10- and 20-cm stairs, the plantar data of normal foot and flatfoot were significantly increased ( < .05).

Conclusions: Orthotic insoles could effectively improve the plantar pressure of flatfoot under different walking conditions. In addition, the arches of normal foot and flatfoot were obviously influenced when walking down stairs. It is, therefore, necessary to wear orthotic insoles for flexible flatfoot to prevent further deformation.