Review article.

To review the epidemiology, etiology, risk factors, prevention, and treatment of neurological complications associated with cervical spine surgery. The article focuses on C5 palsy and intraoperative neurophysiological monitoring.

Neurological problems are the complications most feared by patients and surgeons alike, but, fortunately, spinal cord injury is uncommon. C5 palsy is a less severe but much more common and perplexing problem. Intraoperative monitoring is widely used in cervical spine surgery, but it is unclear how effective it is at preventing spinal cord or nerve root injury.

Narrative and review of the literature.

The incidence of new, severe motor weakness in 2 or more extremities occurring within 12 hours of surgery is 0.18%. The rate in the cervical spine is 3 of 1000. The incidence of isolated C5 palsy is much greater; the rate varies between 0% and 30%, depending on how the condition is defined and which patient group is being analyzed. Numerous theories have been postulated to explain the pathogenesis of C5 palsy, and preventative strategies are discussed. Approximately 70% of patients recover completely without treatment. The mean time to full recovery is 4 to 5 months. Recovery is spontaneous; no treatment has been shown to shorten the time to recovery or improve the recovery rate. A systematic review of the literature found a high level of evidence that multimodal intraoperative monitoring is effective at detecting intraoperative neurological injury. The evidence that intraoperative monitoring reduces the rate of new or worsened perioperative neurological deficits is not as strong. Algorithms help surgeons respond to monitoring alerts and manage neurological deficits that are identified postoperatively.

The keys to managing neurological complications in cervical spine surgery are prevention through careful planning, appropriate multimodal monitoring, meticulous surgical technique, and decisive action when a problem is identified.