Tai Chi has a small positive effect on pain and disability in people with arthritis. Australian authors carried out a systematic review of tai chi as a treatment for chronic musculoskeletal pain. They found that most trials were typically small and of low methodologic quality. Meta-analysis of the results of seven randomised controlled trials showed that the pooled effect size for arthritic populations on a 0-100 scale was 10.1 points for pain reduction and 9.6 points for disability reduction. Additionally, physical performance and health-related quality of life outcomes favored Tai Chi, but of these outcomes, only the level of tension and satisfaction with general health were statistically significant. (The effectiveness of Tai Chi for chronic musculoskeletal pain conditions: a systematic review and meta-analysis. Arthritis Rheum. 2009 Jun 15;61(6):717-24).