I modified a home elliptical machine (the Stamina InMotion) with handles that come up off the foot plates so that my Mom with MS and very limited leg strength can exercise with it.

Here's a video of it in action:

I'm happy with how it came out and my Mom is too.

The elliptical movement gives a much smoother workout than a traditional pedal cycle especially with limited leg strength because there is less distance between the two feet as well as less vertical height change.

This particular elliptical machine is designed to be used while seated so Mom was able to use it right from her scooter (or from a wheelchair). And she had no problem getting her feet into it since the foot plates are low to the ground.

Although it could be used by someone with complete paraplegia, granted it would be passive leg movement but it still might be good for blood flow and also cardio with the arms working.

Curious to know what others think about it.