Article Text

PDF

Review: intra-articular corticosteroid injections are better than placebo for improving symptoms of knee osteoarthritis
  1. Stanford Shoor, MD
  1. Kaiser Permanente Medical Center
 Santa Clara, California, USA

    Statistics from Altmetric.com

    
 
 Q In patients with osteoarthritis (OA) of the knee, are intra-articular corticosteroid injections more effective than placebo for improving symptoms?

    Clinical impact ratings GP/FP/Primary care ★★★★★☆☆ IM/Ambulatory care ★★★★★☆☆ Rheumatology ★★★★★☆☆

    METHODS

    Embedded ImageData sources:

    Medline (1966–2003), EMBASE/Excerpta Medica (1980–2003), the Cochrane controlled trials register, hand searches, references of retrieved articles, and contact with authors.

    Embedded ImageStudy selection and assessment:

    randomised placebo controlled trials (RCTs) that assessed the efficacy of intra-articular corticosteroids of any duration for OA of the knee compared with placebo. Studies were assessed for methodological quality using the Jadad 5 point scale.

    Embedded ImageOutcomes:

    distinct improvement, subjective improvement, decreased pain, overall improvement, clinically relevant outcomes, and response to the OA research scale.

    MAIN RESULTS

    10 studies met the selection criteria (n = 546). The corticosteroids studied were meticortelone, triamcinolone hexacetonide, methylprednisolone, hydrocortisone, and cortivazol. The meta-analysis of 6 pooled studies showed that patients who received intra-articular corticosteroid injections had greater short term (up to 2 weeks) improvement of symptoms than did those who received placebo (table). The pooled results of 2 high quality studies (Jadad score  =  5) also showed long term (16–24 weeks) improvement in OA symptoms (table). However, the individual results of these 2 studies did not differ for OA symptom outcomes. 5 studies (n = 283) that used a visual analogue scale showed improvement in pain up to 2 weeks after corticosteroid injections compared with placebo (weighted mean difference –16.47, 95% CI –22.92 to –10.03).

    Intra-articular corticosteroid injections (ICI) v placebo for osteoarthritis of the knee*

    CONCLUSION

    In patients with osteoarthritis of the knee, intra-articular corticosteroid injections are more effective than placebo for improving symptoms in the short and long term.

    Commentary

    The biological mechanism of corticosteroids suggests that they should be effective in joint disease with significant inflammation—a fact established in the treatment of rheumatoid arthritis. However, how beneficial are corticosteroids in such conditions as OA? The meta-analysis by Arroll et al provides the best answers to date: (1) Intra-articular steroids are modestly better than saline for short term relief of pain. Patients who receive intra-articular corticosteroids are 1.6 times more likely to improve at 2 weeks than those who receive placebo injections (number needed to treat [NNT] = 4). This conclusion is robust, given the results of previous studies,1 the tendency of OA to worsen over time, and the consistency of the findings of this review (7 of 10 trials showed improvement). (2) Corticosteroids appear to have slight benefit at 16–24 weeks (NNT = 5). However, this conclusion was based on only 2 trials, is less consistent with the clinical experience of rheumatologists, and may be dose dependent.

    The review by Arroll et al also raises several questions: which group of OA patients are likely to respond to corticosteroids (ie, those with less severe disease or those with clinical evidence of inflammation such as an effusion)? To what degree is the apparent success of intra-articular steroids affected by how the procedure is performed? For example, how much fluid is withdrawn if lavage is used rather than saline instillation? At what point in the treatment regimen should intra-articular corticosteroids be used (ie, after or before NSAID or physical therapy)? What is the effective and safe interval for repeat injections?

    Unless or until further studies address these issues, clinicians should be reassured that with prudent use, intra-articular corticosteroids remain a valuable option for short term management of OA of the knee.

    References

    View Abstract

    Footnotes

    • For correspondence: Dr B Arroll, University of Auckland, Auckland, New Zealand. b.arroll{at}auckland.ac.nz

    • Source of funding: New Zealand Accident Rehabilitation and Compensation Insurance Corporation.

    Request permissions

    If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.