I just got a vertical mouse and after figuring out how to actually place my hand around it , it may help my stupid fingers.

here's a vertical mouse:

Gingo! :

Yay! It's a little tricky, but once you get it, I think you'll like it.

Wen : it's awkward and I think a bit too big for my hand but it's easy to use

Practice relaxing your grip. You don't need to clench it.