Shoe-Type Walking Assist Device with Controllable Subtalar Joint Alignment at Heel Contact.

In this study, we propose a shoe-type walking assist device that can control the inversion/eversion angle of the subtalar joint during heel contact, with the aim of improving the long-term quality of life of both elderly people and young healthy people. The proposed device enables the heel mechanism to rotate dynamically in the frontal plane to lead the subtalar joint alignment to the neutral position when the heel contacts the ground. The effectiveness of the proposed mechanism was demonstrated by comparing the amount of lateral thrust (lateral sway) during stepping movements with and without the mechanism assist in 5 healthy male subjects wearing the device.

Mechanical Orthosis with Rotation Induction to Lower Leg for Patients with Knee Osteoarthritis.

Knee osteoarthritis (Knee-OA) is a disease caused by age-related muscle weakness, obesity, or sports injury, and it has been estimated to occur in approximately half of all people by the age of 85. One of the characteristics of knee-OA is rotation dyskinesia of the knee joint due to the degeneration of the system around the knee. This rotation movement, a key element of walking, is crucial for impact absorption, balanced walking, and stabilization of the knee joint. In the present study, we focused on the rotation of the lower leg relative to the movement of the ankle joint during the walking stance phase, and we developed a mechanical orthosis that induces rotation of the lower leg in conjunction with the movement of the ankle joint mechanically. The mechanical induction of rotation movement uses the movement difference due to the angle change of the inside and outside bars in conjunction with the ankle angle. We verified the effectiveness of the developed orthosis by measuring the amount of rotation and by administering the Womac test in 5 subjects with knee osteoarthritis. The results confirmed the effectiveness of our orthosis.