I've had some success with a cheapo ergonomic mouse that doesn't require you to twist your wrist so your palm is face down. The more expensive options were often right-handed only. It didn't work on a bare tabletop as your hand and pinky tends to stick and drag on such a surface, but after buying a massive gaming style mouse mat, I was able to use it ("Ergonomic Mouse Left Hand, Jelly Comb")