I can relate to cramping in the fingers of both hands.
There seems to be no pattern or explanation, but once or twice a month my fingers will cramp and deform into a state that I could not duplicate if I tried.
My ring finger will close tight to my palm, while my pinkie and thumb will bend and deform in strange positions. I have learned by now that after a couple of minutes, my fingers will slowly relax and return to normal.
This condition will come on suddenly, and once while attempting to drive, I had a spasm and I was barely able to pull my car off of the road until the spasm gradually relaxed.
I spoke to my neuro, she seemed quite confused as most of my symptoms affect me from the knees down to my feet.
These finger cramps are very sudden and quite painful.
Just another odd symptom that I have experienced since the onset of CIDP.
Good Luck, Barry