The Japanese Scoliosis Society Morbidity and Mortality Survey in 2014: The Complication Trends of Spinal Deformity Surgery from 2012 to 2014

INTRODUCTION: The Japanese Scoliosis Society (JSS) created a longitudinal complication survey of spinal deformity surgery and established the Morbidity and Mortality (M&M) Committee in 2012. The purpose of this study was to analyze the results of the complication survey in 2014 and to report the differences in the complication rates between the years 2012 and 2014. METHODS: A request to participate in this survey was mailed to all JSS members. The questionnaires were sent through e-mail to the members who took part in this survey, and the responses were returned through the same. Diagnosis was grouped into idiopathic scoliosis, congenital scoliosis, neuromuscular scoliosis, spondylolisthesis, pediatric kyphosis and adult spinal deformity. Complication was grouped into death, blindness, neurological deficit (motor or sensory deficit), infection, massive bleeding, hematoma, pneumonia, cardiac failure, DVT/PE, gastrointestinal perforation and instrumentation failure. RESULTS: A total of 2,012 patients were reported from 71 institutes. Overall, complications were observed in 326 patients, and the complication rate increased from 10.4% in 2012 to 15.3% in 2014. The complication rate decreased from 8.8% to 3.7% in idiopathic scoliosis, 21.9% to 15.8% in neuromuscular scoliosis and 26.8% to 0% in kyphosis. The complication rate increased from 6.6% to 14.4% in congenital scoliosis, 9.3% to 12.0% in other types of scoliosis, 3.5% to 14.3% in spondylolisthesis and 21.6% to 26.0% in adult spinal deformity. The rate of neurological deficit, especially in motor deficit, increased from 3.2% to 7.7% in older patients with adult spinal deformity. Instrumentation failure was also more common in patients with adult spinal deformity (5.2% to 5.8%), especially in patients aged 40-65 years (4.4% to 9.1%). CONCLUSIONS: The major complication trends were an increasing rate of neurological deficit and instrumentation failure, especially in adult spinal deformity.