[Diagnostic Testing] Electrophysiological Monitoring during Surgery for Cervical Degenerative Myelopathy and Radiculopathy (PDF)

[Justin]

Journal of Neurosurgery: Spine 11:245–252, August 2009

Electrophysiological Monitoring during Surgery for Cervical Degenerative Myelopathy and Radiculopathy

Daniel K. Resnick, M.D.1, Paul A. Anderson, M.D.2, Michael G. Kaiser, M.D.3, Michael W. Groff, M.D.4, Robert F. Heary, M.D.5, Langston T. Holly, M.D.6, Praveen V. Mummaneni, M.D.7, Timothy C. Ryken, M.D.8, Tanvir F. Choudhri, M.D.9, Edward J. Vresilovic, M.D., Ph.D.10, and Paul G. Matz, M.D.11
1Departments of Neurological Surgery and 2Orthopaedic Surgery, University of Wisconsin, Madison, Wisconsin; 3Department of Neurological Surgery, Neurological Institute, Columbia University, New York, New York; 3Department of Neurosurgery, Mount Sinai School of Medicine, New York, New York; 4Department of Neurosurgery, Harvard Medical School and Beth Israel Deaconess Medical Center, Boston, Massachusetts; 5Department of Neurosurgery, University of Medicine and Dentistry of New Jersey—New Jersey Medical School, Newark, New Jersey; 6Division of Neurosurgery, David Geffen School of Medicine, University of California at Los Angeles, California; 7Department of Neurosurgery, University of California at San Francisco, California; 8Department of Neurosurgery, University of Iowa Hospitals and Clinics, Iowa City, Iowa; 9Department of Neurosurgery, Mount Sinai School of Medicine, New York, New York; 10Department of Orthopaedic Surgery, Milton S. Hershey Medical Center, Pennsylvania State College of Medicine, Hershey, Pennsylvania; and 11Division of Neurological Surgery, University of Alabama, Birmingham, Alabama
Abbreviations used in this paper: CSM = cervical spondylotic myelopathy; EMG = electromyography; EP = electrophysiological; MEP = motor evoked potential; SSEP = somatosensory evoked potential; TcMEP = transcranial MEP.

Address correspondence to: Paul G. Matz, M.D., Neurosurgery and Neurology, LLC, 232 South Woods Mill Road, Chesterfield, Missouri 63017. email: matzpg at yahoo.com.

Object
The objective of this systematic review was to use evidence-based medicine to examine the diagnostic and therapeutic utility of intraoperative electrophysiological (EP) monitoring in the surgical treatment of cervical degenerative disease.

Methods
The National Library of Medicine and Cochrane Database were queried using MeSH headings and key words relevant to cervical spine surgery and EP monitoring. The guidelines group assembled an evidentiary table summarizing the quality of evidence (Classes I–III). The group formulated recommendations that contained the degree of strength based on the Scottish Intercollegiate Guidelines network. Validation was done through peer review by the Joint Guidelines Committee of the American Association of Neurological Surgeons/Congress of Neurological Surgeons.

Results
The reliance on changes in EP monitoring as an indication to alter a surgical plan or administer steroids has not been observed to reduce the incidence of neurological injury during routine surgery for cervical spondylotic myelopathy or cervical radiculopathy (Class III). However, there is an absence of study data examining the benefit of altering a surgical plan due to EP changes.

Conclusions
Although the use of EP monitoring may serve as a sensitive means to diagnose potential neurological injury during anterior spinal surgery for cervical spondylotic myelopathy, the practitioner must understand that intraoperative EP worsening is not specific—it may not represent clinical worsening and its recognition does not necessarily prevent neurological injury, nor does it result in improved outcome (Class II). Intraoperative improvement in EP parameters/indices does not appear to forecast outcome with reliability (conflicting Class I data).

KEYWORDS: electrophysiological monitoring; myelopathy; radiculopathy; practice guidelines; spinal surgery; treatment outcome.

©1944-2009 by the American Association of Neurosurgeons