[General Spine] The Natural History of Cervical Spondylotic Myelopathy (PDF)

[Justin]

Journal of Neurosurgery: Spine 11:104–111, August 2009

The natural history of cervical spondylotic myelopathy

Paul G. Matz, M.D.1, Paul A. Anderson, M.D.2, Langston T. Holly, M.D.3, Michael W. Groff, M.D.4, Robert F. Heary, M.D.5, Michael G. Kaiser, 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 Daniel K. Resnick, M.D.11
1Division of Neurological Surgery, University of Alabama, Birmingham, Alabama; 2Departments of Orthopaedic Surgery and 11Neurological Surgery, University of Wisconsin, Madison, Wisconsin; 3Division of Neurosurgery, David Geffen School of Medicine, University of California at Los Angeles, California; 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; 6Department of Neurological Surgery, Neurological Institute, Columbia University, New York, New York; 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; and 10Department of Orthopaedic Surgery, Milton S. Hershey Medical Center, Pennsylvania State College of Medicine, Hershey, Pennsylvania

Abbreviations used in this paper: AP = anteroposterior; ADL = activities of daily living; CSM = cervical spondylotic myelopathy; EMG = electromyography; ISI = increased signal intensity; JOA = Japanese Orthopaedic Association; mJOA = modified JOA; ROM = range of motion; SEP = somatosensory evoked potential.

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 delineate the natural history of cervical spondylotic myelopathy (CSM) and identify factors associated with clinical deterioration.

Methods
The National Library of Medicine and Cochrane Database were queried using MeSH headings and keywords relevant to the natural history of CSM. Abstracts were reviewed and studies meeting the inclusion criteria were selected. The guidelines group assembled an evidentiary table summarizing the quality of evidence (Classes I–III). Disagreements regarding the level of evidence were resolved through an expert consensus conference. 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 and the Congress of Neurological Surgeons.

Results
The natural history of CSM is mixed: it may manifest as a slow, stepwise decline or there may be a long period of quiescence (Class III). Long periods of severe stenosis are associated with demyelination and may result in necrosis of both gray and white matter. With severe and/or long lasting CSM symptoms, the likelihood of improvement with nonoperative measures is low. Objectively measurable deterioration is rarely seen acutely in patients younger than 75 years of age with mild CSM (modified Japanese Orthopaedic Association scale score > 12; Class I). In patients with cervical stenosis without myelopathy, the presence of abnormal electromyography findings or the presence of clinical radiculopathy is associated with the development of symptomatic CSM in this patient population (Class I).

Conclusions
The natural history of CSM is variable, which may affect treatment decisions.

KEYWORDS: cervical spine; cervical spondylosis; myelopathy; natural history; practice guidelines.

©1944-2009 by the American Association of Neurosurgeons