Intra-articular injections of steroids in the knees have been used for many years to relieve symptoms of osteoarthritis. Godwin and Dawes reviewed the evidence for benefit of this treatment.
The authors used MEDLINE searches, the Cochrane Library, and the Google search engine to identify appropriate controlled clinical trials, systematic reviews, and clinical guidelines of intra-articular steroid injection treatment for osteoarthritis. The articles found in the initial search were used to identify additional references and studies. Treatment guidelines from the American College of Rheumatology and the European League Against Rheumatism were included in their review.
The authors’ search identified only five studies suitable for a meta-analysis. The number of treated patients in the studies ranged from 12 to 60, and the most common agent used was triamcinolone (20 mg). The principal outcome in all five studies was pain, and all used a visual analog scale (VAS) as part of the assessment. The duration of follow-up varied from one to 12 weeks.
One week after injection, patients reported significantly lower VAS scores and had clinically significant improvement compared with placebo. By three to four weeks, the difference in VAS scores was no longer significant in patients treated with triamcinolone. Patients treated with methylprednisolone and cortivazol reported continued benefit at three and four weeks, respectively. No adverse effects were reported. However, about 20 percent of injections were reported to be painful. (Cortivazol is not available in the United States. However, 300 mcg of cortivazol is equivalent in anti-inflammatory activity to about 5 mg of prednisolone.)
The authors note that the studies were conducted by rheumatologists who had experience with correct injection procedure and that the patients had moderate to severe osteoarthritis. The results may not be reproducible in primary care practice. The authors conclude that intra-articular injections of steroids provide short-term relief of pain overall, with rare adverse events, and that this procedure may provide relief for selected patients (e.g., those needing rapid relief of symptoms to participate in an important event or to provide a “bridge” while other medications reach therapeutic levels).