[Clinical characteristics of rheumatoid arthritis with cold pattern knee pain]

To investigate the clinical characteristic of rheumatoid arthritis associated with cold pattern knee joint pain.

The study enrolled 60 patients of RA with the complaint of knee pain, 30 cases with cold pattern and 30 cases without cold pattern. The clinical symptoms, DAS28 score, cold knee score were collected, and serum hypoxia inducible factor-1alpha (HIF-1alpha) erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and thermal texture maps (TTM) of knee temperature were measured. The difference between two groups was compared to analyze the clinical characteristics of RA with cold pattern knee pain.

There were differences between the two groups in the course (t=5.932, P=0.000), DAS28 score (t=2.716, P=0.007), knee (delta TTM) (t=7.731, P=0.000), absolute difference of thermal texture maps between popliteal fossia and front district in knee (ATTM) (t=14.295, P=0.000), CRP (t=5.684, P=0.000), ESR (t=4.506, P=0.000), HIF-1alpha (t=4.817, P=0.000).

RA patients with cold pattern knee pain show the clinical characteristics with longer course of disease, lower level of local inflammation, lower disease activity.