REVIEW Lumbar Fusion for Degenerative Disease: A Systematic Review and Meta-Analysis Daniel Yavin, MD * ‡ Steven Casha, MD, PhD * § Samuel Wiebe, MD, MSc ‡ § ¶ || Thomas E Feasby, MD ‡ § ¶ || Callie Clark, MSc ‡ Albert Isaacs, MD * Jayna Holroyd-Leduc, MD ‡§# R. John Hurlbert, MD, PhD ** Hude Quan, MD, PhD ‡ || Andrew Nataraj, MD ‡‡ Garnette R. Sutherland, MD * § Nathalie Jette, MD, MSc ‡ § ¶ || ∗ Division of Neurosurgery, Department of Clinical Neurosciences, University of Calgary Cumming School of Medicine, Calgary, Canada; ‡ Department of Community Health Sciences, University of Calgary Cumming School of Medicine, Calgary, Canada; § The Hotchkiss Brain Institute, University of Calgary Cumming School of Medicine, Calgary, Canada; ¶ Division of Neurology, Department of Clinical Neurosciences, University of Calgary Cumming School of Medicine, Calgary, Canada; || The O’Brien Institute for Public Health, University of Calgary Cumming School of Medicine, Calgary, Canada; # Department of Medicine, University of Calgary Cumming School of Medicine, Calgary, Canada; ∗∗ Division of Neurosurgery, Department of Surgery, University of Arizona, Tucson, Arizona; ‡‡ Division of Neurosurgery, Department of Surgery, University of Alberta, Edmonton, Canada This work was presented in part at the 51st Annual Congress of the Canadian Neurological Sciences Federation, June 21 to 24, Quebec City, Canada. Correspondence: Nathalie Jette MD, MSc, Professor, Division of Neurology, Departments of Clinical Neurosciences and Community Health Sciences, Canada Research Chair in Neurological Health Services Research, Hotchkiss Brain Institute and O’Brien Institute for Public Health, University of Calgary Cumming School of Medicine, 12th foor, Foothills Medical Centre, 1403 29 Street NW, Calgary, AB T2N 2T9, Canada. E-mail: nathalie.jette@albertahealthservices.ca Received, March 25, 2016. Accepted, January 1, 2017. Published Online, March 17, 2017. Copyright C  2017 by the Congress of Neurological Surgeons BACKGROUND: Due to uncertain evidence, lumbar fusion for degenerative indications is associated with the greatest measured practice variation of any surgical procedure. OBJECTIVE: To summarize the current evidence on the comparative safety and efcacy of lumbar fusion, decompression-alone, or nonoperative care for degenerative indications. METHODS: A systematic review was conducted using PubMed, MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials (up to June 30, 2016). Comparative studies reporting validated measures of safety or efcacy were included. Treatment efects were calculated through DerSimonian and Laird random efects models. RESULTS: The literature search yielded 65 studies (19 randomized controlled trials, 16 prospective cohort studies, 15 retrospective cohort studies, and 15 registries) enrolling a total of 302 620 patients. Disability, pain, and patient satisfaction following fusion, decompression-alone, or nonoperative care were dependent on surgical indications and study methodology. Relative to decompression-alone, the risk of reoperation following fusion was increased for spinal stenosis (relative risk [RR] 1.17, 95% confdence interval [CI] 1.06-1.28) and decreased for spondylolisthesis (RR 0.75, 95% CI 0.68-0.83). Among patients with spinal stenosis, complications were more frequent following fusion (RR 1.87, 95% CI 1.18-2.96). Mortality was not signifcantly associated with any treatment modality. CONCLUSION: Positive clinical change was greatest in patients undergoing fusion for spondylolisthesis while complications and the risk of reoperation limited the beneft of fusion for spinal stenosis. The relative safety and efcacy of fusion for chronic low back pain suggests careful patient selection is required (PROSPERO International Prospective Register of Systematic Reviews number, CRD42015020153). KEYWORDS: Decompression, Fusion, Low back pain, Lumbar spondylosis, Meta-analysis, Spinal stenosis, Spond- ylolisthesis Neurosurgery 80:701–715, 2017 DOI:10.1093/neuros/nyw162 www.neurosurgery-online.com S urgical fusion has become one of the most commonly performed procedures for degenerative disease of the lumbar spine. 1 - 3 Over the past decade, the incidence of lumbar fusion for degenerative indications has more than doubled from 7.5 per 100 000 in 2000 to 17.8 per 100 000 in 2009. 3 , 4 Rising rates of fusion have been accompanied by cost per case increases from $24 676 to $81 960 over the same ABBREVIATIONS: CI, confdence interval; LBP, low back pain; OR, odds ratio; RCT, randomized controlled trial; RR, relative risk; VAS, visual analog scale; WMD, weighted mean diference Supplemental digital content is available for this article at www.neurosurgery-online.com. interval. 4 As a consequence of both escalating rates and costs, the total annual direct expense of fusion in the United States has risen nearly 8-fold to $33.9 billion. 4 The increasingly frequent use of lumbar fusion is complicated by widely varying surgical indica- tions with regional rates differing by up to 20- fold, the greatest measured practice variation of any surgical procedure. 5, 6 Uncertainty resulting from limited scientific evidence contributes to the observed variation in clinical decision making. 5 - 7 While the overuse of lumbar fusion may result in undue complications and the misal- location of resources, decompression-alone or nonoperative care for degenerative indications may risk progressive spinal instability, intractable pain, and neurological impairment. 2 , 8 In the NEUROSURGERY VOLUME 80 | NUMBER 5 | MAY 2017 | 701 Downloaded from https://academic.oup.com/neurosurgery/article-abstract/80/5/701/3073726 by guest on 06 June 2020