To the Editor:
“Epidural Injections for Spinal Pain: A Systematic Review and Meta-analysis Evaluating the ‘Control’ Injections in Randomized Controlled Trials” by Bicket et al.1 is an interesting and thought-provoking article. The authors have provided excellent information in reference to epidural injections of solutions other than steroids. Even though the authors have used an appropriate search strategy and quality assessment, some points of concern persist which may have influenced the conclusions.
As the authors have described, there is a wide variation in design and performance of the trials along with outcome assessments. Thus, it would have been appropriate if they compared local anesthetics versus local anesthetic and steroids, sodium chloride solution versus sodium chloride solution and steroid, sodium chloride solution versus steroid only, local anesthetic versus steroid only, epidural steroid versus intramuscular steroid, and so on in a manner which is much more reliable and understandable.
It seems the authors have missed at least three articles by Manchikanti et al.2–4 and also have used two duplicate articles5–8 providing inadequate analysis. The articles that were missed provided appropriate information similar to that provided by the other nine articles which could bolster the case for equal effectiveness between local anesthetics compared with local anesthetics and steroids.
In addition, the authors have developed an epidural steroid injection technical quality rating. Overall, the quality rating scale seems to be an excellent modality to assess the technical qualities. However, the authors have used some of the qualities which may be inappropriate in some cases such as excluding the patients with previous surgery (studies have been conducted only in postsurgery syndrome) and providing inclusion of patients with pain lasting less than 6 months, two points which are very unusual in chronic pain settings. In addition, the authors have provided only one point for radiographic guidance which should provide much higher importance for fluoroscopic usage and contrast injection, considering that a large number of injections are extra epidural and not target specific.
Hopefully, future studies will address some of the issues raised here.
The authors declare no competing interests.