Risk factors for non-neurological complications in complex adult spinal deformity surgery: an international, large-scale, prospective multi-center study

Abstract

INTRODUCTION: A high-risk of complications had been noted in complex adult spine deformity surgery in previous retrospective studies. The objectives of this study were to establish the prevalence and risk factors for non-neurological complications within the first 6 months of surgery. METHOD: This is an international prospective multi-center study involving 15 sites from North America, Europe, and Asia. Adult patients with severe spinal deformity were followed for 6 months post-operatively. RESULTS: A total of 269 subjects (68% women; 32% men) were included (mean age: 57.8 years). Overall, 60.6% of subjects had at least one complication. The prevalence of intra-operative event, major and minor post-operative complications were 29.4%, 21.6% and 42% respectively. 37% of the patients had multiple complications. Dural tear was the most common intra-operative complication (53%). 32% of major complications were respiratory-related, and 25% were loss of correction and implant failure. Urinary tract infection accounts for 15% of minor complications. 9% of subjects reported new onset or worsening back or leg pain after surgery, accounting for 12% of all minor complications. Previous spine surgery was associated with higher risk of intra-operative events (OR 3.6) and minor complications (OR 3.8), while diabetes (OR 3.8) and lung diseases (OR 3.1) increased the risk of major complications. CONCLUSION: This is the first and the largest prospective study in the world to systematically address non-neurological complications of spine deformity surgery in adults. Our findings contribute to a complete “risk profile” of such patients.