MS eats away at your nerves and makes movement difficult and messes with your sense of touch. One of the issues that this creates is that your normal walking gait is altered because you loose some control of your lower legs. This is the case with my mom.
On Friday, she was fitted with a device that fits on her leg like a knee brace. It has a pickup above the knee and an output below the knee to help transmit the nerve impulse to the lower leg when walking. In trying this out, she apparently walked normally for the first time in years.
The device is not cheap, but it is on par with a set of hearing aids - and for what it can do to help restore normalcy to someone's life it is well worth it.