Figure 2.

Comparison of levels of cytokines in synovial fluid from patients with rheumatoid arthritis (RA) (n = 6) and osteoarthritis (OA) (n = 17) and from non-inflamed normal volunteers (normal) (n = 6). Levels of interleukin (IL)-6 were significantly higher in RA and OA groups (P < 0.05 for both) compared with the normal group (Kruskal-Wallis non-parametric test and Dunn multiple comparison post hoc test). Lines represent median values. TNF, tumour necrosis factor.