That’s a good question. I think there are bikes made for amputees. If anything, I think it’d be best to find a bike maker that can custom make one. For your uncle, I’m sure they can modify handlebars to work with one arm. I mean I have ridden a bike with one hand before, and it can work. But it can be tough to control with the non dominant hand.
They are bikes custom made for amputee, they come with prosthetic attachments. A prosthetic arm made as per your uncle’s specification would be permanently attached to the handle bar and your uncle could connect his arm to that. He can control the brakes and gears with another arm. This kind of bikes provide good balance and more control as he can use his both arm to steer the bike.
It’s cool to think about your uncle and trying to getting him an cycle. Many custom made cycles are available now. You can order them to fit his riding style. You can choose from either MTB or a touring bike. Personally would feel, touring bikes would be more comfortable for him, as they are light and easy to control and he can also ride good distances on them.
Crank shorteners are used to create a more comfortable pedaling motion. They come in various sizes and lengths, and enables to modify the position of the pedal so that it matches the configuration of the body and bike.
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