Herbal therapy for treating osteoarthritis

BACKGROUND: The increasing popularity of complementary and alternative medicine appears to be particularly evident amongst people with chronic diseases. In the treatment of osteoarthritis, one therapy that has been identified as having potential benefit is plant and herbal medicine (phytotherapy). OBJECTIVES: To determine the effectiveness of herbal therapies in treating osteoarthritis. SEARCH STRATEGY: Databases for mainstream and complementary medicine were searched using terms to include all forms of arthritis combined with herbal medicine. We searched the following electronic databases: Cochrane Musculoskeletal Group register, Cochrane Complementary Medicine Field register, Cochrane Controlled Trials Register (CCTR), MEDLINE, EMBASE, CISCOM, AMED, CINAHL, Dissertation Abstracts and BIDS ISI. We also searched the reference lists from retrieved trials. SELECTION CRITERIA: All randomized trials of herbal interventions in osteoarthritis, compared to placebo. Studies were included according to an a priori protocol and agreement was reached between two reviewers who independently read each selected paper for content and assessment of quality. Papers of any language were included. DATA COLLECTION AND ANALYSIS: Data were extracted independently by the same two reviewers. MAIN RESULTS: Five studies (four different herbal interventions) met the review criteria. Two studies were suitable for data pooling. It was not possible to draw firm conclusions from the single studies but the two combined studies of avocado/soybean unsaponifiables showed beneficial effects on functional index, pain, intake of non-steroidal anti-inflammatory drugs (NSAIDs) and global evaluation. No serious side effects were reported. AUTHORS' CONCLUSIONS: The evidence for avocado-soybean unsaponifiables in the treatment of osteoarthritis is convincing but evidence for the other herbal interventions is insufficient to either recommend or discourage their use.