Sounds very very awful. I really sympathise cos I have had bad weakness in left hand & arm & found I felt much worse than with weakness in the leg. I still have some weakness with loss of dexterity-typing with left hand difficult, buttons, very difficult & I have to sit down when I try to do them up or I fall over. I cannot take meds much cos I am so allergic but have found that Progurt has improved the hand 50%. Made by an American here in Sydney you buy sachets and make up yogurt at home. I find one sachet makes enough yogurt for appros 10 days so cost is nearly same as buying yogurt from store. (if you are interested there is a website)
I have a Baclofen pump which is wonderful help with pain & spasticity but makes me shake when I stand up. I think this is cos baclofen can make you weak but I have found since I have started doing Wii Fit, balance games
and stepper shaking/rocking has improved a lot. Building up strength maybe? Maybe a programme to strengthen hands might help?? But I know that this is v.v. difficult to do.
Wishing you all the best. Popsie