It's very likely that it's monotritis because of the symptoms. To be sure of diagnosis, you need to do thorough evaluations and interviews to learn more about your history and how you live. You need to test your feet and evaluate your coordination. You need to scan your arm's MRI to look at your affected nerves better.
Doctor, your right hand has been hanging out for a while, and it's getting worse and worse, and your hands and your forearms are going down, and what's the problem?