The Use of Intra-articular Corticosteroid Injection to Treat Osteoarthritis of the Carpometacarpal Joint: A Randomized Control Trial

Background & Significance:

The burden of chronic diseases such as osteoarthritis (OA) is increasing globally, having a major impact on both health services and society. 1,2 The CMC joint of the thumb is the most commonly affected joint in the upper extremity by OA, and may lead to pain, decreased hand function and poor health-related quality of life. 3-6 The prevalence of CMC OA varies depending on the population being studied and is not yet well defined. Haara et al. 6 reported age-adjusted CMC OA prevalence of 7% in men and 15% in women among adults thirty years of age or older in Finland. The ROTTERDAM study7 showed that 67% of the women and 54.8% of the men had OA in at least one hand joint, with 35.8% occurring at the CMC joint. The Framingham Study reported higher prevalence of symptomatic hand OA in women (26.2%) compared to men (13.4%) aged 70 year or older. Symptomatic participants in this cohort had 10% reduced maximal grip strength, reported more difficulty with activities of daily living such as writing, handling, or fingering small objects (odds ratio = 3.4), and increased difficulty lifting over 10-pound objects (odds ratio = 1.7 and 1.6, respectively).8

Treating CMC OA is challenging, since evidence is contradictory. A study looking at the natural history of hand OA over a 6 year period showed variation in pain and functional changes, with half of the population reporting deterioration of symptoms and the other half reporting improvements of outcomes with different treatments. 9 Clinical changes (pain and function) and radiographic progression of CMC OA were not related in this study. 9 Non-operative management (i.e. splints, medications, physiotherapy) is usually the first choice of treatment for symptomatic CMC OA, followed by surgery if failed non-operative management. 3,10 Current non-operative guidelines for treatment of hand OA are based on a combination of research findings and expertise opinion. 11-13 2007EULAR, 2012 American College of Rheumatology and 2014 NICE guidelines recommendations for the treatment of hand OA include general considerations (i.e. clinical presentation, risk factors and associated diseases), non-pharmacological (i.e. splint, education, exercises, thermal modalities), and pharmacological (i.e. pain medications, oral and topical anti-inflammatories, opioids) approaches. 11-13 2007EULAR and 2014 NICE also recommend intra-articular corticosteroid injections as an adjunct treatment if patients didn't respond to other treatment approaches, even though evidence is weak.11,13

Effectiveness of guided intra-articular injections for CMC OA evidence is inconsistent. There is only one published RCT looking specifically at efficacy of corticosteroid injections in CMC OA that found no clinical benefit from intra-articular corticosteroid injection to moderate to severe CMC OA compared with placebo injection. This study ended earlier due to recruitment issues and is underpowered to detect true differences between groups. 14 A meta-analysis investigating intra-articular injections of corticosteroids or hyaluronic acid in thumb OA stated that corticosteroids may be helpful in decreasing pain and hyaluronic acid in improving pulp pinch force in a period of 5 to 6 months. 15 Due to high heterogeneity of included studies in this meta-analysis, the evidence is still inconclusive. Another RCT compared the efficacy of intra-articular hyaluronic acid and corticoid injections in CMC OA and found that both study groups had decreased pain and improved function when compared to baseline data, with no significant differences between groups. 16 A recent systematic review on non-surgical therapies for hand OA found inconsistent evidence when comparing intra-articular steroids and placebo. 17 They found three RCTs comparing intra-articular steroids to placebo, with two studies showing no difference and one study showing significant improvement in pain with movement between groups.17

Based on the lack of strong evidence regarding the use of guided corticosteroid injections to treat CMC OA, this randomized clinical trial (RCT) will compare 6-months outcomes following fluoroscopic guided injections of corticosteroid plus local anesthetic or saline (placebo) plus local anesthetic in adult participants with carpometacarpal osteoarthritis (OA).