I have been meaning to post back to this thread for the last week.
I have now had blood test and seen a rheumatologist. Both suggested arthritis was highly unlikely.
I have also seen John Ostrovskis at the clinic in Sheffield. He did some manipulations, strength tests and an ultrasound scan. Following this, I am 100% certain that I have torn the collateral ligament on the ulnar side of the DIP in my right hand, close to the proximal attachment. He said that an avulsion is possible but not visible on the scans.
Apparently this type of injury is pretty much unresponsive to rest, so I have been having shockwave therapy to help stimulate repair and I'm cautiously optimistic that this is helping. Progressive loading also encouraged, not sure exactly how much pain is acceptable when climbing though so need to ask him next time. If you are Sheffield based, or anywhere local, I would absolutely recommend you go and see him, I wish I had gone 2 months ago.
Have not experimented with voodoo flossing, but I think you have to wrap in tight in elastic (piece of theraband for eg) and then move it through the full range of motion.
