Prediction of Postoperative Clinical Outcome in Cervical Spondylotic Myelopathy

Authors: D. Štěpánek ;  S. Žídek ;  D. Bludovský ;  M. Choc ;  V. Přibáň ;  I. Holečková
Authors‘ workplace: LF UK a FN Plzeň
Published in: Cesk Slov Neurol N 2014; 77/110(1): 39-46
Category: Original Paper


In this retrospective study we outline the relationship between a chosen surgical approach as it relates to the localization of spinal cord lesion assessed by the use of evoked potentials and the effect of this approach on the postoperative state of patients with cervical spondylotic myelopathy.

The study, from 2006 to 2010, comprised 65 patients with clinical signs of cervical myelopathy. These patients had been indicated for surgery, which subsequently was performed by using either the anterior –  A or posterior –  P approach. The patients were assessed using Nurick and mJOA scores before surgery, then at 12, 24 months after surgery. In addition, they were preoperatively examined with a battery of evoked potentials (EP) –  somatosensory evoked potential (SEP) and motor evoked potential (MEP) tests. Based on EP, principal spinal cord disability was determined: A –  anterior (maximum changes in MEP), P –  posterior (maximum change in SEP). The entire group was, on the basis of EP partitioning and the surgical approach used, divided into four groups: Aa, Ap, Pa, Pp. The results of individual examinations were compared within groups and in between groups.

Objective postoperative improvement mJOA score was found in all four groups. Statistically significant improvement was, however, detected only in the groups of anterior approaches regardless of the primacy of SEP or MEP lesion (Aa: p = 0.011, Ap: p = 0.005). Overall mJOA improvement was revealed in 65 % patients in this study.

Objectively significant postoperative improvements were achieved with anterior approaches, regardless of the fact whether the dominant spinal cord pathology was located ventrally or dorsally. As a result of this study, there seems to be no benefit to choosing a surgical approach based on the localization of dominant spinal cord pathology assesses by EP.

Key words:
spondylotic cervical myelopathy – motor evoked potentials – somatosensory evoked potentials – surgical decompression

The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study.

The Editorial Board declares that the manu­script met the ICMJE “uniform requirements” for biomedical papers.


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