Comparative Effectiveness of Tai Chi Versus Physical Therapy for Knee Osteoarthritis: A Randomized Trial

Abstract

Background: 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.

Objective: To compare Tai Chi with standard physical therapy for patients with knee osteoarthritis.

Design: Randomized, 52-week, single-blind comparative effectiveness trial. (ClinicalTrials.gov: NCT01258985).

Setting: An urban tertiary care academic hospital.

Patients: 204 participants with symptomatic knee osteoarthritis (mean age, 60 years; 70% women; 53% white).

Intervention: 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).

Measurements: 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.

Results: 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.

Limitation: Patients were aware of their treatment group assignment, and the generalizability of the findings to other settings remains undetermined.

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

Primary funding source: National Center for Complementary and Integrative Health of the National Institutes of Health.

Conflict of interest statement

Disclosures: Dr. Schmid reports grants from Brown University during the conduct of the study and personal fees from Pfizer outside the submitted work. Dr. Harvey reports grants from Samumed, AbbVie, and Fidia Pharma outside the submitted work. Dr. Fielding reports grants from the National Institutes of Health during the conduct of the study; grants from Nestlé, Regeneron, Astellas Pharma, and Pronutria Biosciences outside the submitted work; personal fees from Nestlé, Regeneron, Astellas Pharma, Pronutria Biosciences, GlaxoSmith-Kline, ICON, and Biophytis outside the submitted work; and nonfinancial support from Pronutria and Myosyntax outside the submitted work. Dr. Wong reports grants from the Patient-Centered Outcomes Research Institute and the Rheumatology Research Foundation of the American College of Rheumatology and nonfinancial support from the European League Against Rheumatism outside the submitted work. Authors not named here have disclosed no conflicts of interest. Disclosures can also be viewed at www.acponline.org/authors/icmje/ConflictOfInterestForms.do?msNum=M15-2143.

Figures

Figure 1

Study flow diagram. * Two participants were inadvertently randomly assigned twice. Data from the first randomization were analyzed using the intention-to-treat principle.

Figure 2

Mean change in outcomes, by treatment group. Measurements were obtained at baseline and at 12, 24, and 52 wk, but data points are offset slightly for clarity. SF-36 = 36-item Short Form Health Survey; WOMAC = Western Ontario and McMaster Universities Osteoarthritis Index.