Corticosteroid injections and pain relief in RC tendinopathy
This meta-analysis found that corticosteroid injections did not outperform placebo injections in reducing pain in patients with rotator cuff (RC) tendinopathy at the 3-month follow-up.
A limited, temporary reduction in pain was present between 4 and 8 weeks post injection. At least 5 patients needed to be treated to obtain such a small short-term pain relief in one patient. Additional injections did not improve outcomes.
Corticosteroid injections into the subacromial space are widely used as a treatment option for RC tendinopathy, but the ability of these injections to improve symptoms – and more precisely, relieve pain – attributed to RC tendinopathy is up for debate.
Although there have been various randomised controlled trials (RCTs) and even some systematic reviews, there is no clear-cut conclusion on this topic yet. Partially, this has to do with the use of insufficient statistical analysis methods and outcome measures that are of little relevance for clinicians.
The current meta-analysis included 11 RCTs (among which 2 studies that were published after the last systematic review) and specifically set out to determine the number needed to treat (NNT), i.e., the number of patients that receive an injection before one patient experiences more improvement in symptoms than a placebo would give.
It was found that no pain reduction was present in patients with RC tendinopathy 3 months after the corticosteroid injections were administered.
A slight yet temporary pain relief was present at assessments less than 2 months post injection. For every 5 patients undergoing an injection, one will experience a small and short-term pain relief. Multiple injections were not more effective than a single injection.
The authors state that, given the results of this meta-analysis, there are not many arguments in favour of corticosteroid injections, on the contrary: the injection itself causes a certain amount of pain and discomfort, and potential adverse effects to tissue quality and associated costs should also be considered.
Want to read deeper into this topic? A free full-text version of this study is available online here!
Expert opinion by Willem-Paul Wiertz
This meta-analysis contains a comprehensive and good-quality discussion, in which the authors examine the limitations and delve into the effect that a small number of studies may have had on (especially short-term) results .
In line with this, they pay attention to the extent to which these temporary results are really meaningful for the patients or not.
They also place this study within the overall body of research concerning corticosteroid injections and provide a clear and concise conclusion regarding their use as treatment option for RC tendinopathy.
> From: Mohamadi, Clin Orthop Relat Res 475 (2017) 232-243. All rights reserved to The Association of Bone and Joint Surgeons. Click here for the online summary.