How Do I Realistically Write a Character Who Can Only Use One Arm?

Cerebral palsy would work for your character, but you’ll need to keep in mind how broad and complex a diagnosis it is. Cerebral palsy is never one thing. It’s not just a weak limb or a strong startle reflex. It’s a thousand tiny, frustrating things that change the way our bodies operate.

As far as do’s and don’t go:

Do hire a sensitivity editor that matches your characters condition before publishing it.

Do read work by disabled authors that write disabled characters. Consume the kinds of stories you want to create.

Do a lot of research. When you feel like you have a solid grasp of how your character’s disability might affect them—keep going.

Do talk to people who have a condition similar to the character you’re trying to write. Value their input and their time (this means either paying them or not abusing their generosity).

Do realize that you can do a lot of harm. You have the potential to reinforce or perpetuate harmful tropes and stereotypes.

Don’t think that any amount of research, or (professional) editing will make you immune from criticism. At the end of the day, You’re writing in a voice and from a view that you do not have. This in and of itself can be problematic.

Don’t think that any amount of research or time with a sensitivity editor gives you a pass to write whatever kind of story you want without backlash. People are going to disagree with what you are trying to do. Frankly, I disagree with what you are trying to do—if only because it’s been done before and ultimately harmed the disabled community more than helped.

To be clear: I’m not saying “Don’t”. Not necessarily. What I am saying is “Pay attention and tread carefully”. There’s a chance you could write something great, if you take the time and put in the effort to do it right.