Objective: To evaluate trials of acupuncture for osteoarthritis (OA) of the knee, to assess the methodologic quality of the trials and determine whether low-quality trials are associated with positive outcomes, to document adverse effects, to identify patient or treatment characteristics associated with positive response, and to identify areas of future research.
Methods: Eight databases and 62 conference abstract series were searched. Randomized or quasi-randomized trials of all languages were included and evaluated for methodologic quality using the Jadad scale. Outcomes were pain, function, global improvement, and imaging. Data could not be pooled; therefore, a best-evidence synthesis was performed to determine the strength of evidence by control group. The adequacy of the acupuncture procedure was assessed by 2 acupuncturists trained in treating OA and blinded to study results.
Results: Seven trials representing 393 patients with knee OA were identified. For pain and function, there was limited evidence that acupuncture is more effective than being on a waiting list for treatment or having treatment as usual. For pain, there was strong evidence that real acupuncture is more effective than sham acupuncture; however, for function, there was inconclusive evidence that real acupuncture is more effective than sham acupuncture. There was insufficient evidence to determine whether the efficacy of acupuncture is similar to that of other treatments.
Conclusion: The existing evidence suggests that acupuncture may play a role in the treatment of knee OA. Future research should define an optimal acupuncture treatment, measure quality of life, and assess acupuncture combined with other modalities.