Comment on: Ultrasound-guided erector spinae plane block vs modified thoracolumbar interfascial plane block in lumbar spine surgeries

Dear Editor, We read with great interest the article by Mogahed et al.[1] on ultrasound-guided (USG) erector spinae plane block (ESPB) vs modified thoracolumbar interfascial plane block (mTLIP) in lumbar spine surgeries and we wish to reflect our views on it. First, Mogahed et al.[1] identified T10 level by palpatory method and then performed ESBP under ultrasound guidance by placing the probe 3 cm later to the marked T10 level. Identifying the vertebral level under USG is important as palpatory method poorly corresponds with actual vertebral level.[2] Hence, it is better to identify vertebral level under USG starting from caudal to cranial or cranial to caudal direction.[3] Second, for reporting of results of various study parameters, though authors mentioned about 95% confidence interval (CI) next to P value, they have not mentioned the range values of CI. The range of CI directly reflects the true estimate of the effect. CI is influenced by factors like sample size (narrower CI range for larger sample size and vice versa) and data dispersion (more dispersion—wider CI) with narrower CI range giving better estimate. CONSORT (Consolidated Standards of Reporting Trials) recommend mention of CI values for reporting of the results.[4,5] Under results sections, authors state that “There was a small statistical difference between the block groups but of not a clinical significance at 6 h postoperatively with (P = 0.011) (with 95% CI).” Thus, once again, mention of lower and upper values of CI could have allowed readers to interpret clinical significance over statistical significance as rest of the values comparing two intervention groups of the study are non-significant. Lastly, we respectfully disagree with the authors that this was the first study using ropivacaine for comparing ESPB with mTLIP as a systematic review and meta-analysis (SRMA) quoting few studies has been already published.[6] Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.