Comparative effectiveness of Tai Chi versus physical therapy for knee osteoarthritis

Few remedies effectively treat long-term pain and disability from knee osteoarthritis. Studies suggest that Tai Chi alleviates symptoms, but no trials have directly compared Tai Chi with standard therapies for osteoarthritis.

The purpose of this 52-week, randomized, single-blind comparative effectiveness trial was to compare Tai Chi with standard physical therapy for patients with knee osteoarthritis. The trial took place in an urban tertiary care academic hospital. A total of 204 participants with symptomatic knee osteoarthritis (mean age, 60 years; 70% women; 53% white) took part in Tai Chi (2 times per week for 12 weeks) or standard physical therapy (2 times per week for 6 weeks, followed by 6 weeks of monitored home exercise).

The primary outcome was Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score at 12 weeks. Secondary outcomes included physical function, depression, medication use, and quality of life.

At 12 weeks, the WOMAC score was substantially reduced in both groups (Tai Chi, 167 points [95% CI, 145 to 190 points]; physical therapy, 143 points [CI, 119 to 167 points]). The between-group difference was not significant (24 points [CI, -10 to 58 points]). Both groups also showed similar clinically significant improvement in most secondary outcomes, and the benefits were maintained up to 52 weeks. Of note, the Tai Chi group had significantly greater improvements in depression and the physical component of quality of life. The benefit of Tai Chi was consistent across instructors. No serious adverse events occurred. Patients were aware of their treatment group assignment, and the generalizability of the findings to other settings remains undetermined, which are important limitations to the trial.

Tai Chi produced beneficial effects similar to those of a standard course of physical therapy in the treatment of knee osteoarthritis.