About 6 weeks ago I developed a knot in the knuckel of my left hand. Its on the palm side of the hand in the joint closest to the hand. Its not just swelling. There is something hard there. A bone spur maybe? I have been playing for over 20 years so I would think that if my left hand fingerings were the problem I would have had problems long ago. Only thing I can think of is that I have for a few months been working on a way to play scales up and down the neck that uses lots of slides with the first finger. I have cut back to 30 min a day playing time from from my normal 3-4 hrs but after a month the knot is still there. Any of you ever had this problem?