Study design: Retrospective study of adult patients who underwent spinal surgery over a 10-year period at a single institution.
Objective: New onset postoperative paralysis remains one of the most feared complications of spinal surgery. The goal of this study was to determine the incidence and etiology of new onset major neurologic deficit immediately after adult spinal surgery.
Summary of background data: Previous studies, focusing on specific disease entities, have shown incidence rates of significant spinal cord or cauda equina injury after spinal surgery ranging from approximately 0% to 2%.
Methods: The authors reviewed the quality assurance records for adult patients who underwent spinal surgery over a 10-year period (July 1, 1996 to June 30, 2006) by surgeons in the Department of Neurosurgery, University of Cincinnati College of Medicine at hospitals affiliated with the neurologic surgery residency program. Patients with new onset major neurologic deficit immediately after spinal surgery were identified.
Results: Of 11,817 adult spinal operations, 21 patients experienced new onset major neurologic deficit immediately after spinal surgery, yielding an overall incidence of 0.178%; in the cervical spine 0.293%, thoracic spine 0.488%, and lumbar/sacral spine 0.0745%. The difference in incidence between spinal regions was statistically significant (P = 0.00343). The etiology of the neurologic deficits was confirmed with reoperation and/or postoperative imaging studies: epidural hematoma in 8 patients, inadequate decompression in 5 patients, presumed vascular compromise in 4 patients, graft/cage dislodgement in 2 patients, and presumed surgical trauma in 2 patients. Placement of spinal instrumentation was performed in 12 of 21 patients (57.1%) and was associated with a significantly higher risk of new onset major neurologic deficit immediately after spinal surgery (P = 0.022).
Conclusions: The incidence of new onset major neurologic deficit immediately after adult spinal surgery is low. Epidural hematoma and inadequate decompression were the most common etiologies in this series of patients.