You mind getting arthritis at an earlier age at your finger joints? If so, I can give you a few exercises =P.

I'll think of some regular safe ones when my eyes aren't bloodshot and sleepy.

Start with hanging on a pullup bar. Hang dead arm for as long as possible then do the same with4,3,2 fingers and then you can take a dip belt and add weigth to that and hang. Exercises without wrist wraps such as deadlifts and bench press are key too.

Yup, hanging off a pull up bar by your fingers were one of the good exercises I knew, but I was also told it causes a lot of stress on the finger joints so I wasn't sure if it was exactly the safest.

I used to do pull ups with my fingers hanging though, instead of just hanging.