Utility of Intraoperative Neuromonitoring

  • Randy S. D’Amico
  • Peter D. Angevine


Intraoperative neurophysiological monitoring (intraoperative neuromonitoring, IONM) permits evaluation of the functional integrity of the spinal cord and spinal nerve roots and provides an opportunity to detect, and possibly reverse, neurological injury during high-risk spine surgery. As a result, IONM has become routinely used as a surgical adjunct in cases of myelopathy or radiculopathy due to degenerative cervical spine disease. Several monitoring modalities are currently available including somatosensory evoked potentials (SSEP), transcranial motor evoked potential (tcMEP), and spontaneous electromyography (S-EMG). In general, multimodality monitoring is performed to maximize diagnostic potential. Current evidence suggests that multimodality neuromonitoring may be useful to detect intraoperative neurological injury during anterior and posterior cervical spine operations for the treatment of degenerative cervical myelopathy and radiculopathy. However, the efficacy of IONM may be limited in “low-risk” anterior cervical spine surgery, cases of significant preoperative myelopathy and/or radiculopathy, and in the detection and prevention of delayed-onset C5 palsies.


Neurophysiological monitoring Neuromonitoring Cervical Spine Cervical spine Transcranial motor evoked potential Somatosensory evoked potentials Spontaneous electromyography Myelopathy Radiculopathy 



Anterior cervical discectomy and fusion


Cervical spondylotic myelopathy


Intraoperative neurophysiological monitoring


Mean arterial pressure


Motor evoked potential


Magnetic resonance


Spinal cord injury


Spontaneous electromyography


Somatosensory evoked potential


Transcranial motor evoked potential


Total intravenous anesthesia


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© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.Department of Neurological SurgeryColumbia University Medical CenterNew YorkUSA

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