The effectiveness of intradermal sterile water injection for low back pain in the ED: A prospective, randomized controlled trial

Intradermal water injection to alleviate low back pain?

Believe it or not, water injection has been around for many years, especially in the delivery suite. There are some proposed mechanisms as to why or how it might work.

But can water injection work in the Emergency Department?

These authors from a single center in Turkey, randomized low back pain patients who all got IV NSAIDS to either intradermal water injection or nothing else.

Inclusion criteria were adults 18-65 years old with a VAS pain score of >4. They excluded trauma, chronic back pain, those that had pain medications prior to arrival, diabetes, or BMI >30.

Outcomes were reduction of pain at 10, 20, 30 minutes and 24 hours. They also looked at patient satisfaction, need for rescue medication, etc.

Results?

112 patients enrolled and the water worked FANTASTIC! Everything they could measure was better.

Hallelujah… we have a miracle!

Unfortunately, there are some serious problems with this study.

The manuscript is awful and serves as a red flag as to the professionalism and conduct of these researchers. I would have genuinely believed that they used Google Translate and submitted a draft without changes. But there are words in the manuscript that don’t even exist on Google!

Regardless of the sloppy manuscript, there are serious methodological issues that likely render the conclusions invalid.

It was not blinded.

Of course, patients were not blinded, but nor were the clinicians in the study who also collected the outcome measures. This could have resulted in substantial subject and observer bias.

And of course, there is the placebo effect…

(But to be fair to these researchers, what is the placebo for water? Or how can you perform sham water injection? I don’t know.)

In short summary, this terribly presented paper’s findings are very likely due to bias and placebo effect.

But is it unethical to use undisclosed placebo? Holy hallelujah can of worms…

 

Covering:

Tekin E, Gur A, Bayraktar M, et al. The effectiveness of intradermal sterile water injection for low back pain in the emergency department: A prospective, randomized controlled study. Am J Emerg Med 2021;42:103-109. [link to article]