Mechanically Actuated Stance-Control-Orthoses: Advantages, Design Evaluation and Future Directions

Abstract

Engineers and researchers have devotedly sought to improve and develop the design of walking assistive devices in last few decades to enhance the mobility of impaired individuals. The progress is quite impressive but a lot of design challenges are still remain in making these designs user-friendly and commercially viable. Patients with weak quadriceps have limited option to walk independently. Knee-ankle-foot orthosis (KAFO) are typically prescribed as walking assistive device. KAFOs keep the knee in full extension to provide knee stability during walking and keep knee straight throughout the gait cycle with mechanical locking system. Locked knee in the swing phase leads to an abnormal gait pattern. Mechanical stance control orthosis (SCO) is designed to release the lock during swing phase to allow free knee motion and lock it again during stance phase with mechanical actuation system. It helps the user to walk more natural way by overcoming the limitations of KAFO. This article discusses the advantages of SCOs over KAFOs, analyses various mechanisms, shows comparison and future directions to overcome design challenges. This article will help the researchers in assistive technology to develop a reliable and user-friendly product for common users with lower cost.