Hi I have RA and OA in both hands - I used to have that problem as my trapezium (bone at base of thumb) was deteriorating. My nickname was "crash" and my husband was threatening to buy plastic dishes. I literally never knew when the thumb would work, and was afraid to touch anything. I had surgery, and they patched me back together. Last year I had the other one fixed. Now I can do quite a lot - not a lot of strength, but a lot less pain, and no dropping.

The procedure is called a carpal metacarpal repair (CMC), and it is one of the most common orthopedic surgeries. Maybe that is what is happening with your hand?
Sue