1. Motivation

Introduction

• After a spinal cord injury, stroke, or other nerve damage, many people suffer from a gait abnormality called foot drop
• Weakness in the Tibialis Anterior muscle makes it so that a person is unable to raise their foot from their ankle
• One solution is to use an ankle foot orthosis (AFO), which locks the ankle in the required position
• This means that the user does not need to use their own muscles to lift their ankle, which impedes long-term recovery
• Another solution is to use functional electrical stimulation (FES) to electrically stimulate necessary muscles while walking.
• This project focuses on creating a better FES device to help those suffering from foot drop

Motivation

One of our team members suffered from a spinal cord injury and thus, has a lot of weakness in his lower body. To aid with his walking, he uses an FES device on the quadriceps but is constantly thinking of different ways it could be made better. Thus, we decided to address his frustrations by creating a device that would not only be a 100 times cheaper but also fix some of the issues he is having. This includes challenges in activating the device, changing settings, relying on a pressure sensor and much more. However, for this project, we decided to focus on a smaller muscle, the Tibialis Anterior, since it is more common for someone to have foot drop.

Brief History of FES

• Functional Electrical Stimulation (initially known as Functional Electrotherapy by Liberson) was developed in the 1960s with it's first application for foot drop
• Later, as research continued on these devices, almost every muscle in the body can be contracted using FES
• It is a very common form for rehabilitation after a spinal cord injury or stroke as it prevents muscle atrophy and send the signals back up the spinal cord
• Many devices are commercially available but are incredibly expensive