In a study on twenty consecutive patients, Huang concluded IL-20 induces proinflammatory, chemotaxtic, and matrix degradative responses in the intervertebral disc, suggesting IL-20 plays a critical role in the pathogenesis of disc herniation.6 In addition, IL-20 is also involved in inflammatory diseases such as psoriasis, atherosclerosis, and rheumatoid arthritis, indicating IL-20 is an important inflammation factor correlated to the chronical bone and joint disease. Here, IL20 is linked to rheumatoid arthritis.