Sounds like CF related arthritis to me. Mine used to come in "flare-ups" and I would also get a high fever. I have suffered from it since I was 9...I am now 35. UGGHHH!! Hot baths definitely help relieve the soreness...at least for a while. Anti-inflammatories...definitely. Mine eventually got so bad that I was on Celebrex for about 3 years...and then that no longer helped. I had to resort to prednisone because nothing else helped. I now have arthritis all the time..not just flare ups. I have been seeing a rheumatologist for quite some time and he has now put me on methotrexate. So far, it seems to be doing ok. The overall soreness is not quite as bad as it was before. Good Luck to you..
Dea
35 w/CF