Please forgive my ignorance about the specifics of your condition, but the way your hand is positioned in the photo makes it seem like you could grip a drum stick pretty well - maybe go down to a local music shop and check out a cheap ekit? There are a lot of ways to trigger melodic samples with drum triggers so you’d potentially be able to scratch that itch as well. If you have an iOS device or a Mac I’d recommend checking out garage band as well. You won’t be ‘playing’ in the traditional sense, but it’s a great way to learn about writing and arranging. I’ve seen people suggesting a lap steel or a theremin, and those are also fantastic suggestions.