Prediction of Anterior Vs . Posterior Surgical Approach for Degenerative Cervical Myelopathy Based on MRI Pathology : Analysis of a Global Cohort

: 42026 Prediction of Anterior Vs. Posterior Surgical Approach for Degenerative Cervical Myelopathy Based on MRI Pathology: Analysis of a Global Cohort Aria Nouri MD MSc, Allan R. Martin MD PhD, So Kato MD, Christopher D. Witiw MD MS, Anick Nater MD, Lindsay Tetreault PhD, Carlo Santaguida MD, Hamed Reihani-Kermani, MD, David Gimbel MD, Rani Nasser MD, Joseph S. Cheng MD MS, Michael G. Fehlings MD PhD Department of Neurosurgery, Yale University School of Medicine, USA Department of Neurosurgery, University of Cincinnati College of Medicine, USA Division of Neurosurgery, University of Toronto, Canada Montreal Neurological Institute and Hospital, McGill University, Canada Neuroscience Research Center, Kerman University of Medical Sciences, Iran Disclosure: MGF Consulting agreements with Pfizer, Zimmer Biomet, and InVivo Therapeutics. All other authors have nothing to disclose. CS – Speaker for Medtronic and Stryker; Consulting agreements Stryker; Research Support CSL Behring Acknowledgement: Study data collection was supported with funding from AOSpine INTRODUCTION Degenerative Cervical Myelopathy (DCM) encompasses a spectrum of disorders including cervical spondylotic myelopathy (CSM) and ossification of the posterior longitudinal ligament (OPLL), which cause neurological impairment through compressive or dynamic injury of the spinal cord(Nouri et al., 2015). The natural history of patients with DCM is typically progressive and non-operative management has shown limited clinical utility. Therefore, surgery is typically offered to decompress the spinal cord and stabilize the cervical spine, with the aim of arresting the disease process and to promote neurological recovery. The decision to approach the spine from an anterior, posterior or less commonly from a combined approach dependents on multiple factors (Lawrence et al., 2013b, Nouri et al., 2017b, Emery, 2015), and it is recognized that considerable heterogeneity exists among surgeons in terms of their preferred approach(Nouri et al., 2017b). While both anterior and posterior options appear to result in similar outcomes when baseline clinical and imaging features are controlled for(Kato et al., 2017), it remains unclear if one approach is superior than the other when both approaches would be a viable options (Figure 1). To address this controversy, a prospective multicenter randomized controlled trial is currently underway which is randomizing patients into anterior or posterior surgery for situations where there is equipoise between anterior and posterior surgical techniques(Ghogawala et al., 2014). To better understand the influence of clinical and imaging features on the decision to undertake an anterior vs. posterior approach, we analyzed data obtained from two large multicenter prospective studies conducted in North America and internationally. Herein, we use a systematic approach to analyze MRIs and see how well preoperative imaging and clinical features are able to predict the choice of an anterior or posterior surgical approach. Figure 1. Mid-sagittal T2 weighted MRIs of 3 patients with DCM illustrating different pathology. A) The patient is presenting with focal anterior compression of the cord most prominent at the C6-7 disk and mild kyphosis. Based on the literature, such pathology is likely to consistently receive anterior surgery. B) The patient is presenting with multilevel anterior and posterior compression, and spondylolisthesis, but good lordosis. Based on the literature, this patient is likely to consistently receive posterior surgery. C) The patient is presenting with anterior cord compression spanning 3 levels from C4-7, lordosis and relatively preserved intervertebral disk space. Three levels of compression is a common demarcation at which surgeons choose to approach the spine posteriorly, however, this is not definitive, and many surgeons would prefer an anterior choice. Advocates for a posterior approach could contend that lordosis, multilevel pathology and relative maintenance of disc space supports a posterior approach, while advocates for anterior surgery could argue that the large anterior compression is not directly being addressed by a posterior approach and may result in residual compression. 1 https://clinicaltrials.gov/ct2/show/NCT02076113