Study design: Retrospective review of a prospectively collected, multicenter database.
Objective: To assess the rates of new neurologic deficit (NND) associated with spine surgery.
Summary of background data: New neurologic deficit is a potential complication of spine surgery but previously reported rates are often limited by small sample size and single-surgeon experiences.
Methods: The Scoliosis Research Society morbidity and mortality database was queried for spinal surgery cases complicated by NND from 2004 to 2007, including nerve root deficit, cauda equina deficit, and spinal cord deficit. Use of neuromonitoring was assessed. Recovery was stratified as complete, partial, or none. Rates of NND were stratified based on diagnosis, age (pediatric, <21 years; adult, ≥21 years), and surgical parameters.
Results: Of the 108,419 cases reported, NND was documented for 1,064 (1.0%), including 662 nerve root deficits, 74 cauda equina deficits, and 293 spinal cord deficits (deficit not specified for 35 cases). Rates of NND were calculated on the basis of diagnosis. Revision cases had a 41% higher rate of NND (1.25%) compared with primary cases (0.89%; P < 0.001). Pediatric cases had a 59% higher rate of NND (1.32%) compared with adult cases (0.83%; P < 0.001). The rate of NND for cases with implants was more than twice that for cases without implants (1.15% vs. 0.52%; P < 0.001). Neuromonitoring was used for 65% of cases, and for cases with new nerve root deficit, cauda equina deficit, and spinal cord deficit, changes in neuromonitoring were reported in 11%, 8%, and 40%, respectively. The respective percentages of no recovery, partial, and complete recovery for nerve root deficit were 4.7%, 46.8%, and 47.1%, respectively; for cauda equina deficit, they were 9.6%, 45.2%, and 45.2%, respectively; and for spinal cord deficit, the percentages were 10.6%, 43%, and 45.7%, respectively.
Conclusion: Our data demonstrate that even among skilled spinal deformity surgeons, NNDs are inherent potential complications of spine surgery. These data provide general benchmark rates for NND with spine surgery as a basis for patient counseling and for ongoing efforts to improve safety of care.