A Measurement System for Deformation and Torsion Angle in Plastic Ankle Foot Orthoses

Abstract

We developed a displacement and torsion measurement system comprising a linear sensor system that directly measures PAFO deformation with very high accuracy. This system enables highly accurate and direct measurement and is free from measurement errors caused by infrared reflection. Using this system, we report the relation between deformation and angle in walking tests. Seven healthy men participated in experiments using this system with stride lengths set to 300 mm and cadence to 80 step/min. As a result of the walking analysis revealed that the toe or heel part of the PAFO was constrained between the floor and the foot immediately after the initiation of stance phase, and terminal stance phase, and adduction torsion occurred because the load was generated to cause plantar flexion. After that, consequently, it can be seen that due to the load shift and the flexibility act of the PAFO, the adduction torsion is decreased.