Is there a place for intra-articular corticosteroid injections in the treatment of knee osteoarthritis?

### What you need to know The prevalence of end-stage knee osteoarthritis requiring joint replacement is increasing globally.1 Some of this increase is due to increasing obesity and worsening lifestyle factors such as poor physical activity. It also requires us to evaluate whether standard treatments for mild to moderate osteoarthritis are effective. Intra-articular corticosteroid, also referred to as corticosteroid injection, is widely prescribed for osteoarthritis of the knee. Guidelines, such as those produced by the National Institute for Health and Care Excellence (NICE),2 have traditionally supported its use,3 but reviews of efficacy indicate a high degree of uncertainty.45 On average, a patient might have symptomatic knee osteoarthritis for 30 years. It is uncertain how the long term safety or harms of corticosteroid injection balance against the likelihood of short term pain improvement. Systematic reviews indicate low quality evidence that intra-articular corticosteroid injections may provide short term pain relief and a small improvement in physical function for up to six weeks in knee osteoarthritis compared with placebo.46 Patients with more severe disease are likely to experience greater improvement.7 The benefits are not seen to last beyond three months in trials,4 although individual patients may report longer periods of symptom relief. There is considerable heterogeneity between trials. While corticosteroid injections have been found to be safe in …