Portal de Periódicos da CAPES

The evidence gap in low back pain management strategies – Authors' reply

2021; Elsevier BV; Volume: 398; Issue: 10306 Linguagem: Inglês

10.1016/s0140-6736(21)01810-9

1474-547X

Nebojša Nick Knežević, Steven P. Cohen,

Pain Management and Placebo Effect

We thank Xing Du and Yunsheng Ou for bringing up the contentious issue of spine surgery for further discussion. However, we do not agree that the conclusions in our Seminar1Knezevic NN Candido KD Vlaeyen JWS Van Zundert J Cohen SP Low back pain.Lancet. 2021; 398: 78-92Summary Full Text Full Text PDF PubMed Scopus (19) Google Scholar oppose evidence-based medicine; rather, we believe that they bolster the argument that there is insufficient evidence to draw firm conclusions. If we are seeking evidence-based results to determine whether surgery is more effective than conservative treatment, we ought to exclude the systematic review of cohort studies by Fritsch and colleagues2Fritsch CG Ferreira ML Maher CG et al.The clinical course of pain and disability following surgery for spinal stenosis: a systematic review and meta-analysis of cohort studies.Eur Spine J. 2017; 26: 324-335Crossref PubMed Scopus (29) Google Scholar in favour of systematic reviews of randomised controlled trials,3Kovacs FM Urrútia G Alarcón JD Surgery versus conservative treatment for symptomatic lumbar spinal stenosis: a systematic review of randomized controlled trials.Spine (Phila Pa 1976). 2011; 36: e1335-51Crossref PubMed Scopus (185) Google Scholar, 4Zaina F Tomkins-Lane C Carragee E Negrini S Surgical versus non-surgical treatment for lumbar spinal stenosis.Cochrane Database Syst Rev. 2016; 2016CD010264Google Scholar because the placebo effect for interventional therapies such as surgery is extraordinarily high.5Kaptchuk TJ Stason WB Davis RB et al.Sham device v inert pill: randomised controlled trial of two placebo treatments.BMJ. 2006; 332: 391-397Crossref PubMed Scopus (378) Google Scholar Furthermore, the Cochrane systematic review4Zaina F Tomkins-Lane C Carragee E Negrini S Surgical versus non-surgical treatment for lumbar spinal stenosis.Cochrane Database Syst Rev. 2016; 2016CD010264Google Scholar that Du and Ou cited reached different conclusions from the systematic review3Kovacs FM Urrútia G Alarcón JD Surgery versus conservative treatment for symptomatic lumbar spinal stenosis: a systematic review of randomized controlled trials.Spine (Phila Pa 1976). 2011; 36: e1335-51Crossref PubMed Scopus (185) Google Scholar we included in our Seminar, because the study selection criteria were different. Although there are inherent limitations when including only randomised controlled trials when evaluating spine surgery (eg, large numbers of crossover patients that can underestimate the effect of surgery with intention-to-treat analysis; strong surgical candidates with focal neurological signs are often excluded), we concur with Du and Ou that there are not enough randomised controlled trials to come to valid and widely accepted generalisable conclusions. We also agree that spine fusion might be warranted in cases of symptomatic spinal stenosis accompanied by clinically relevant instability, but the indication for spine fusion in this scenario is the spine instability, not the stenosis per se. Too often, surgeons pre-emptively fuse the spine during decompression surgery in cases for which there is no evidence to support this practice. We also thank Estanislao Arana and Francisco Kovacs for their comments. We believe that throughout our Seminar,1Knezevic NN Candido KD Vlaeyen JWS Van Zundert J Cohen SP Low back pain.Lancet. 2021; 398: 78-92Summary Full Text Full Text PDF PubMed Scopus (19) Google Scholar we emphasised as sufficiently as possible (within the allotted word limit) that routine imaging is not required for patients with low back pain. In fact the opening sentence of Arana and Kovacs’ Correspondence supports the contention that “MRI has not been shown to improve outcomes for patients who are candidates for epidural steroid injection”.6Cohen SP Gupta A Strassels SA et al.Effect of MRI on treatment results or decision making in patients with lumbosacral radiculopathy referred for epidural steroid injections: a multicenter, randomized controlled trial.Arch Intern Med. 2012; 172: 134-142Crossref PubMed Scopus (30) Google Scholar Furthermore, a review of Medicare's National Claims History by Lurie and colleagues,7Lurie JD Birkmeyer NJ Weinstein JN Rates of advanced spinal imaging and spine surgery.Spine (Phila Pa 1976). 2003; 28: 616-620Crossref PubMed Google Scholar which showed a positive correlation between advanced spinal imaging and spine surgery, neither established that imaging was used inappropriately, nor corroborated a cause-and-effect relationship between imaging and spine surgery. For example, brain MRIs nearly always precede brain surgery and there is almost certainly a strong, positive correlation between the two, but this observation does not prove that brain imaging is overused or leads to unnecessary surgery. The systematic review by Kamper and colleagues8Kamper SJ Logan G Copsey B et al.What is usual care for low back pain? A systematic review of health care provided to patients with low back pain in family practice and emergency departments.Pain. 2020; 161: 694-702Crossref PubMed Scopus (26) Google Scholar shows clearly that usual care, as dispensed by family doctors and emergency medicine physicians, is also characterised by overuse of spine imaging. This suggests that other forces besides financial benefit are driving the overuse of radiological examinations, such as practising defensive medicine or maximising patient satisfaction scores. Everyone can agree that low back pain is a complex problem and deciding the most relevant topics and pertinent treatment options to discuss within the constraints of a Seminar was, to some degree, a matter of subjective judgment. Consequently, we were forced to exclude many worthwhile, evidence-based manage-ment strategies, such as the one Arana and Kovacs mentioned in their Correspondence. SPC reports personal fees from SPR Therapeutics, Avanos, Scilex–Sorrento, Persica, and the US Department of Justice and reports grants from Avanos and Scilex–Sorrento, outside the submitted work. NNK declares no competing interests. Low back painLow back pain covers a spectrum of different types of pain (eg, nociceptive, neuropathic and nociplastic, or non-specific) that frequently overlap. The elements comprising the lumbar spine (eg, soft tissue, vertebrae, zygapophyseal and sacroiliac joints, intervertebral discs, and neurovascular structures) are prone to different stressors, and each of these, alone or in combination, can contribute to low back pain. Due to numerous factors related to low back pain, and the low specificity of imaging and diagnostic injections, diagnostic methods for this condition continue to be a subject of controversy. Full-Text PDF The evidence gap in low back pain management strategiesIn their Seminar,1 Nebojsa Nick Knezevic and colleagues concluded that surgery is more effective than conservative management in the treatment of lumbar spinal stenosis, and that decompression combined with fusion had no substantial benefit compared with decompression alone. We believe that this conclusion was not evidence-based, and could have the potential to prejudice the spine surgeon against the choice of treatment for lumbar spinal stenosis. Full-Text PDF The evidence gap in low back pain management strategiesIn their Seminar1 on low back pain, Nebojsa Nick Knezevic and colleagues state that “MRI…can contribute to higher rates of spine surgery and result in higher satisfaction rates”. Full-Text PDF