Pain in hand osteoarthritis is associated with crystals in the synovial fluid: a cross-sectional study of people with hand osteoarthritis undergoing surgery oleh Philip G Conaghan, Robin Christensen, Lene Terslev, Marius Henriksen, Henning Bliddal, Karen Ellegaard, Mikael Boesen, Philip Hansen, Lars Juul, Janus Damm Nybing, Anna Dossing, Lisa K. Stamp, Geraldine M. McCarthy, Niels Henrik Søe, Dimitar Ivanov Radev