High-Risk Surgical Maneuvers for Impending True-Positive Intraoperative Neurologic Monitoring Alerts: Experience in 3139 Consecutive Spine Surgeries

Abstract

BACKGROUND: Intraoperative neurologic monitoring (IONM) has become an essential component for decreasing the incidence of spinal cord injury during spine surgeries. Many high-risk surgical maneuvers that result in significant IONM alerts have not been reported systematically. Our objective was to thoroughly summarize some common high-risk surgical points associated with IONM alerts in various spine surgeries.

METHODS: Between November 2010 and April 2017, 62 patients with true-positive IONM alerts from 3139 spine surgeries were enrolled. Transcranial motor evoked potentials, somatosensory evoked potentials, and free-run electromyography were used for IONM. All 62 patients were identified as true-positive IONM cases.

RESULTS: Of 3139 patients, 101 demonstrated significant IONM changes-62 true-positive cases, 14 false-positive cases, and 25 indeterminate IONM results. IONM alerts most often occurred in thoracic screw placement (n = 10, 16.1%), osteotomy (n = 22, 35.5%), correction (n = 19, 30.6%), and spinal cord decompression (n = 11, 17.8%). Appropriate timely measures are indicated in response to IONM alerts during high-risk surgical maneuvers. Ten (10/62, 16.1%) patients showed permanent postoperative neurologic deficits.

CONCLUSIONS: IONM alerts are often associated with some specific high-risk surgical maneuvers. Careful and timely observation is crucial.