My health has been an issue too, as I have picked up my long-neglected viin. I have MS, which makes my hands & fingers numb. I persist in using my hands for violin, knitting, and cooking, and I think pushing through helps retain function. Periods of inactivity worsen my symptoms. MS, like RA, is an autoimmune disease, and though they are very different diseases, perhaps my experience is not too unique? Basically, use it or lose it. And, like another poster here, I have found my flexibility & some sensitivity improves with yoga, exercise, healthy Paleo diet, and homeopathy.