Comparison of Outcomes between Anterior and Posterior Cervical Procedures: Results of Surgery Involving Four or More Vertebral Levels from the AOSpine North America Cervical Spondylotic Myelopathy Study

IntroductionDebate continues about the relative merits of anterior versus posterior surgery for multilevel cervical stenosis causing myelopathy. Conclusions from previous studies were limited because one- or two-level anterior surgeries have been compared with multilevel posterior cases. The objective of this study was to compare outcomes and complications of anterior versus posterior-based cervical procedures (≥ 4 levels) for patients with multilevel disease.Material and MethodsData from the AOSpine North America Cervical Spondylotic Myelopathy Study, a prospective, multicenter study, were analyzed. A subset of patients with myelopathy involving four or five vertebrae was analyzed in this study. The outcome measures included NDI, modified-Japanese Orthopaedic Association scores, SF36v2, and Nurick grades. Adverse events were also collected in a standardized manner and externally monitored. Rates of perioperative complications (within 30 days of surgery) and delayed complications (31 days–2 years followin...