Osteoarthritis of the knee is the most common form of arthritis and causes pain and declines in physical function. National and international recommendations highlight combined non-pharmacological (training) and pharmacological treatment as an optimal treatment approach, but such combinations have not been studied before. In this randomized clinical trial of 100 patients with knee osteoarthritis we compared intra-articular injection of corticosteroid into the painful knee with placebo injection. 2 weeks after injection all participants underwent a 12-week physical therapy exercise program. The results were evaluated in both short and long term at clinical visits and included self-reported pain and other osteoarthritis-related symptoms, physical function, and imaging and laboratory markers of inflammation. There were no differences between the corticosteroid and placebo in any of the outcomes - neither in short nor long term, i.e. a steroid injections do not influence the effectiveness of a subsequent exercise program.
The results of the study are important in the daily clinical practice where many patients with osteoarthritis are being treated with steroid injections in anticipation of less inflammation and thus a better opportunity for rehabilitation. Following the results of this study, such clinical practice is unsupported.
The article is accepted for publication in JAMA Internal Medicine.