I have been asked 1000 times what is wrong with my hands
I'd do a variation on Corsair's thing. "Well, there was that fingernail that I had removed because of a tumor - dang fingernail never did grow in right, and of course, there is the arthritis and carpal tunel that is acting up right now, and the grease is from yesterday......"

I've never done it, but it would make 'em run, not walk from my general vicinity.