Randomized Trial of Epidural Injections for Spinal Stenosis Published in The New England Journal of Medicine: Further Confusion Without Clarification

Randomized controlled trials are considered the hallmark of evidence-based medicine. This conveysthe idea that up-to-date evidence applied consistently in clinical practice, in combination withclinicians’ individual expertise and patients own preference/expectations are enjoined to achievethe best possible outcome. Since its inception in 1990s, evidence-based medicine has evolvedin conjunction with numerous changes in the healthcare environment. However, the benefits ofevidence-based medicine have not materialized for spinal pain including surgical interventions.Consequently, the debate continues on the efficacy and medical necessity of multiple interventionsprovided in managing spinal pain.Friedly et al published a randomized controlled trial of epidural glucocorticoid injections for spinalstenosis in the July 2014 edition of the highly prestigious New England Journal of Medicine,.This was accompanied by an editorial from Andersson. This manuscript provided significantsensationalism for the media and confusion for the spine community. This randomized trial ofepidural glucocorticoid injections for spinal stenosis and accompanying editorial concluded thatepidural injections of glucocorticoids plus lidocaine offered minimal or no short-term benefit ascompared with epidural injections of lidocaine alone, with the editorial emphasizing proceedingdirectly to surgical intervention. In addition media statements by the authors also emphasized theidea that exercise or surgery might be better options for patients suffereing from narrowing ofthe spinal canal.The interventional pain management community believes that there are severe limitations tothis study, manuscript, and accompanying editorial. The design, inclusion criteria, outcomesassessment, analysis of data and interpretation, and conclusions of this trial point to the fact thatthis highly sophisticated and much publicized randomized trial may not be appropriate and leadto misinformation.The design of the trial was inappropriate with failure to include existing randomized trials, withinclusion criteria that did not incorporate conservative management,or caudal epidural injections.Simultaneously, acute pain patients were included, multilevel stenosis and various other factorswere not identified. The interventions included lumbar interlaminar and transforaminal epiduralinjections with highly variable volumes of medication being injected per patient. Outcomesassessment was not optimal with assessment of the patients at 3 and 6 weeks for a procedurewhich provides on average 3 weeks of relief and utilizing an instrument which is more appropriatelyutilized in acute and subacute low back pain. Analysis of the data was hampered by inadequatesubgroup analysis leading to inappropriate interpretation. Based on the available data epidurallocal anesthetic with steroids was clearly superior at 3 weeks and potentially at 6 weeks. Further,both treatments were effective considering the baseline to 3 week and 6 week assessment,appropriate subgroup analysis seems to have yielded significant superiority for interlaminarepidural injections compared to transforaminal epidural injections with local anesthetic with orwithout steroids specifically with proportion of patients achieving greater than 50% improvementat 3 and 6 week levels. This critical assessment shows that this study suffers from a challenging design, was premised on the exclusion of available highquality literature, and had inadequate duration of follow-up for an interventional technique with poor assessment criteria andreporting. Finally the analysis and interpretation of data has led to inaccurate and inappropriate conclusions which we do notbelieve is based on scientific evidence.Key words: Chronic low back pain, central spinal stenosis, epidural injections, local anesthetics, steroids, randomized trials,outcomes assessment