Several of our older Elves have pain at the base of their thumb making it difficult for them to grip and hold tools. The trapaziometacarpal joint (also known as carpometacarpal [CMC], or basal joint of the thumb) is a saddle shaped joint just above the wrist and allows the thumb to move freely into flexion, abduction, adduction and extension.

When the joint is arthritic movement becomes limited, particularly opening the hand fully, and grip can be reduced. We know that the incidence of osteoarthritis at the base of the thumb increases with age, is more common in women and can also be associated with knee arthritis.

Although the Elves enjoy activity sometimes it can be difficult to exercise this joint because of pain and these Elves asked if steroid injection might help. We looked and found this study which asked whether intra-articular injection of corticosteroid leads to pain relief and increased function in people with osteoarthritis of the thumb, and how long do any effects last.

Here’s what they did

They searched Cochrane, PubMed and Google Scholar databases up to June 2010. Studies were included if they examined the effect of injection of corticosteroid, with or without local anaesthetic, into the CMC joint of the thumb for osteoarthritis and assessed either pain relief and/or functional improvement as an outcome. They excluded studies that included injection into other joints, surgical interventions or those not directly assessing response to steroid injection; descriptive studies or reviews, and papers not published in English. Independent analysis was undertaken by two reviewers using a Critical Appraisal Skills Programme (CASP) tool, randomised controlled trials (RCTs) were appraised using the CONSORT checklist. Meta-analysis was not possible due to heterogeneity, therefore the authors produced a narrative review.

Here’s what they found

Nine relevant studies were found, four RCTs and five prospective case series with 307 participants ranging from 39 to 93 years of age. Outcomes measured included VAS, DASH, range of movement, grip strength and reported stiffness or tenderness. Varying dosages of steroid were used and no adverse events were recorded in any of the studies.

• Eight studies reported varying degrees of improvement in pain with benefit lasting between 4 weeks and 12 months. Two studies reported benefit lasting at least six months.
• Of the six studies where the injection was performed ‘blind’ without radiological guidance, all reported improved pain relief in the short term.
• One study reported that radiologically guided steroid injection had no benefit over placebo in moderate to severe OA.

The authors concluded

There are potentially significant although short term benefits to be gained from steroid injection.

There are potentially significant but short term benefits from steroid injection

The Musculoskeletal Elf’s view

 Osteoarthritis of the thumb can significantly limit function and grip. Although the number of studies included in this review was small and the outcomes measured variable, it would appear that corticosteroid injection is a safe and effective treatment in the short term.

I was interested to see that ‘blind’ injections were no less effective in reducing pain than those performed under radiological guidance. In our woodland we x-ray prior to injection and refer only those with difficult to access joints for injection under ultrasound guidance. Right, better tell the Elves!

What do you think?

• How effective have you found steroid injection in managing osteoarthritis of the thumb?
• What other management strategies do you use?

Send us your views on this blog and become part of the ever expanding Musculoskeletal Elf community. Post your comment below, or get in touch via social media (Facebook, Twitter, LinkedIn, Google+).

Links

Fowler, A., Swindells, M. G., & Burke, F. D. (2015). Intra-articular corticosteroid injections to manage trapeziometacarpal osteoarthritis—a systematic review.HAND, 1-10.

• PRISMA statement
• EQUATOR Network