Unexplained chronic wrist pain in my family

Hi,

I'm looking for help with an unexplained wrist problem in my family. My mother has suffered with pain in her wrists, hands and arms for many years. She has been in and out of hospital many times with no satisfactory diagnosis. The problem seemed to start when hand washing nappies at around age 34 when she had my sister and has been a consistent problem ever since. In the past, the pain has increased so much that she would drop things or not be able to complete ordinary tasks in daily life.
Many things seem to make the problem flare up including use of a computer, driving, knitting, even fairly normal use of wrists. Around 3 years ago, my sister developed the same problem. A waitressing job as well as a lot of computer use seemed to bring on the same symptoms and once they start, they don't go away. She has also seen a lot of doctors and no one seems to be able to explain the problem. An operation with only a 20% success rate was suggested but since it would leave extensive scarring, it wasn't worth it. They have both tried splints and arm rests but neither helps.
Now at the age of 21, I've suddenly started to have the problem as well. Almost anything seems to make it flare up and the only thing that can avert it is to remove all use of the wrists and hands as much as possible to bring it back down to a manageable level until it flares up again. The trouble is that I work as a musician (trumpet) and drive around a lot and it seems that the problem will almost certainly affect this.
None of us has ever suffered injuries to the wrists or arms and as far as I know, they are not deformed in any way. I'd be very grateful if anyone could suggest what the problem with our wrists might be or could point me in the direction of some further research.