In reply to David Coley: I've had this recently and seen a GP and a consultant.
It's the sheath on the finger tendons catching when you fold and unfold your fingers.
It's very common but beware of the options for "curing" this.
I had a cortisone injection first. It works for some but not for everyone. It may last. It may not.
Mine did not work.
I saw the consultant who said they could operate to resolve it so I went ahead.
It's a quick operation as a day patient with a local anasthetic.
After that for me it has been a nighmare.
My incision would not heal and it had to be redressed every couple of days.
After a couple of weeks I still could not drive and was in serions pain.
I was admitted via casualty in severe pain after three weeks and operated on again 24 hours after admission with a full anasthetic and was kept in for 7 days on a saline drip.
It has healed well now but I was only allowed one physio appointment and I do those exercises daily, have my hand in bowls of hot water and use an exercise ball to try and get more flexibility in my hand. The two fingers operated on are still swollen and I still cannot make a fist so I have a hand that is much worse than it was before the operation in early May 2015!
I can drive now but compensate for what I cannot do.
When I saw the physio she said I shouldn't have had the operation.
OK this could happen to anyone but if I had been told about the percentage chances of these problems I would not have had this operation and consequently I would not recommend it.
I don't play guitar but if I did, before the operation, I couldn't do it now because my fingers bend only half the distance that they did.
As an aside I have three friends who strangely had the same operation at a similar time and two of those still have the issues that I have.