This is not an issue I am dealing with, but please listen me out.
Part of my post cancer wellness care brought me into a heated therapy
pool and "Range of Motion" exercises for 1 hour. There were many, up
to 20 per class, and the issues were many, stroke, frozen joints, MS,
etc. One class had 6 walker users and one wheelchair who was hoisted
into the water. The class was the same for all, and it was not
possible to discern one from another. All were doing the same motion
at the same time and the instructor made certain every joint and
muscle was moved. Fingers were part of a "playing the piano"
exercise, while moving under water left to right and back, the
fingers were playing the keys. Another was as mentioned by Ronda,
pulling the hand back as much as possible and then pushing it down
using the opposite hand, then switching. Stretching fingers
individually. Making a tent with all fingertips touching, then one
pair at a time separate them, circling them around each other right
to left and then left to right. Just try that and see how you can
make that work, it is indeed a challenge.
What I saw accomplished in that class alone, and what I was able to
do myself was great. My balance improved measurably, I was able to
stand on one foot and actively move the other, no way was I able to
do that outside of the pool, and I had done yoga in the past. Run
warm water into your tub or sink, get your hands under water and
stretch, pull, push, open wide, clench tightly.
Do follow the advice for a medical evaluation for nerve impingement
or other reasons. See how tightly you do clench, and consider using
your left hand for the torch, I also am somewhat ambidextrous and
keep the torch in my left hand and do finer motions with my right.
Works rather well for me.
Good luck for a quick solution.