Weird Rash!

Hi, I have suffered with arthritis for some years but it is becoming worse with age ( as it does!) Over the past 2 yrs, my hands have become a lot worse, especially the my thumbs at the joint with the palm. I was referred back to rheumatology in November and I was told that it was just average wear and tear but if I'm honest, the pain doesn't feel 'bony', more like I've torn a muscle or tendon in it.
Also, since late October I have been periodically developing a blistery type rash on the sides of my hands which is itchy. It's only happeningon the arthritic nodules on the outer side, mostly on my right hand but slightly on the left as well, but a few weeks ago, the rash happened on the outer fleshy part of my left hand as well although this has now more or less gone. I did mention it to the rheumy but I think ke was more impressed with impressing his student than looking into my condition, bless him. I even had to ask him to xray my hands! Any one else have this rash?