Magnetic resonance diffusion tensor imaging in patients with cervical spondylotic spinal cord compression: correlations between clinical and electrophysiological findings.

STUDY DESIGN: A prospective study evaluating a cohort of patients with spondylotic cervical spine compression. OBJECTIVE: To analyze the potential of diffusion tensor imaging (DTI) of the cervical spinal cord in the detection of changes associated with spondylotic myelopathy, with particular reference to clinical and electrophysiological findings. SUMMARY OF BACKGROUND DATA: Conventional magnetic resonance imaging (MRI) may provide confusing findings because of a frequent disproportion between the degree of the spinal cord compression and clinical symptoms. The DTI is known to be more sensitive to subtle pathological changes of the spinal cord compared with conventional MRI. METHODS: The DTI of the cervical spinal cord was performed within a group of 52 patients with spondylotic spinal cord compression and 13 healthy volunteers on a 1.5-T MRI scanner. All patients underwent clinical examination that differentiated between asymptomatic and symptomatic myelopathy subgroups, and 45 patients underwent electrophysiological examination. We measured the apparent diffusion coefficient and fractional anisotropy of the spinal cord at C2/C3 level without compression and at the maximal compression level (MCL). Sagittal spinal canal diameter, cross-sectional spinal cord area, and presence of T2 hyperintensity at the MCL were also recorded. Nonparametric statistical testing was used for comparison of controls with subgroups of patients. RESULTS: Significant differences in both the DTI parameters measured at the MCL, between patients with compression and control group, were found, while no difference was observed at the noncompression level. Moreover, fractional anisotropy values were lower and apparent diffusion coefficient values were higher at the MCL in the symptomatic patients than in the asymptomatic patients. The DTI showed higher potential to discriminate between clinical subgroups in comparison with standard MRI parameters and electrophysiological findings. CONCLUSION: The DTI appears to be a promising imaging modality in patients with spondylotic spinal cord compression. It reflects the presence of symptomatic myelopathy and shows considerable potential for discriminating between symptomatic and asymptomatic patients.

Cervical spondylotic myelopathy: conservative versus surgical treatment after 10 years.

It is not known whether the results of decompressive surgery to treat the mild and moderate forms of spondylotic cervical myelopathy (CSM) are any better than those of a conservative approach. A 10-year prospective randomised study was performed. The objective of the study was to compare conservative and operative treatments of mild and moderate, non-progressive, or slowly progressive, forms of CSM. Sixty-four patients were randomised into two groups of 32. Group A was treated conservatively while group B was treated surgically. The clinical outcome was evaluated by modified JOA score, timed 10-m walk, score of daily activities recorded by video and evaluated by two observers blinded to the type of therapy, and by subjective assessment by the patients themselves. Seventeen patents died of natural, unrelated causes, during the follow-up. A total of 25 patients in the conservatively and 22 in the surgically treated group were used for the final evaluation. There was no statistically significant difference between both groups in mJOA score, in subjective evaluation by the patients themselves and in evaluation of video-recordings of daily living activities by two observers blinded to treatment mode. There was neither any difference found in the percentage of patients losing the ability to walk nor in the time taken to cover the 10-m track from a standing start. Comparison of conservative and surgical treatment in mild and moderate forms of CSM in a 10-year follow-up has not shown, on average, a significant difference in results. In both groups, patients get better and worse. According to the power analysis it is necessary admit that these results possess the low ability to answer definitely the question which treatment is better for the patients with a mild and moderate non-progressive CSM because of the low number of patients for the final evaluation and for clinically negligible differences between two compared arms. These findings can serve as a worthy odds-on hypothesis which needs the confirmation.

Are subjects with spondylotic cervical cord encroachment at increased risk of cervical spinal cord injury after minor trauma?

The aim of the study was to analyse the risk of symptomatic myelopathy after minor trauma in patients with asymptomatic spondylotic cervical spinal cord encroachment (ASCCE). In a cohort of 199 patients with ASCCE, previously followed prospectively in a study investigating progression into symptomatic myelopathy, the authors looked retrospectively for traumatic episodes that may have involved injury to the cervical spine. A questionnaire and data file analysis were employed to highlight whatever hypothetical relationship might emerge with the development of symptomatic myelopathy. Fourteen traumatic episodes in the course of a follow-up of 44 months (median) were recorded in our group (who had been instructed to avoid risky activities), with no significant association with the development of symptomatic myelopathy (found in 45 cases). Only three minor traumatic events without fracture of the cervical spine were found among the symptomatic myelopathy cases, with no chronological relationship between trauma and myelopathy. Furthermore, 56 traumatic spinal cord events were found before the diagnosis of cervical cord encroachment was established, with no correlation to either type of compression (discogenic vs osteophytic). In conclusion, the risk of spinal cord injury after minor trauma of the cervical spine in patients with ASCCE appeared to be low in our cohort provided risky activities in these individuals are restricted. Implementation of preventive surgical decompression surgery into clinical practice in these individuals should be postponed until better-designed studies provide proof enough for it to take precedence over a conservative approach.

Presymptomatic spondylotic cervical myelopathy: an updated predictive model.

Spondylotic cervical cord compression detected by imaging methods is a prerequisite for the clinical diagnosis of spondylotic cervical myelopathy (SCM). Little is known about the spontaneous course and prognosis of clinically "silent" presymptomatic spondylotic cervical cord compression (P-SCCC). The aim of the present study was to update a previously published model predictive for the development of clinically symptomatic SCM, and to assess the early and late risks of this event in a larger cohort of P-SCCC subjects. A group of 199 patients (94 women, 105 men, median age 51 years) with magnetic resonance signs of spondylotic cervical cord compression, but without clear clinical signs of myelopathy, was followed prospectively for at least 2 years (range 2-12 years). Various demographic, clinical, imaging, and electrophysiological parameters were correlated with the time for the development of symptomatic SCM. Clinical evidence of the first signs and symptoms of SCM within the follow-up period was found in 45 patients (22.6%). The 25th percentile time to clinically manifested myelopathy was 48.4 months, and symptomatic SCM developed within 12 months in 16 patients (35.5%). The presence of symptomatic cervical radiculopathy and electrophysiological abnormalities of cervical cord dysfunction detected by somatosensory or motor-evoked potentials were associated with time-to-SCM development and early development (< or =12 months) of SCM, while MRI hyperintensity predicted later (>12 months) progression to symptomatic SCM. The multivariate predictive model based on these variables correctly predicted early progression into SCM in 81.4% of the cases. In conclusion, electrophysiological abnormalities of cervical cord dysfunction together with clinical signs of cervical radiculopathy and MRI hyperintensity are useful predictors of early progression into symptomatic SCM in patients with P-SCCC. Electrophysiological evaluation of cervical cord dysfunction in patients with cervical radiculopathy or back pain is valuable. Meticulous follow-up is justified in high-risk P-SCCC cases.

Presymptomatic spondylotic cervical cord compression.

STUDY DESIGN: We conducted a cohort study of clinically asymptomatic spondylotic cervical cord compression cases with the primary end point of the development of clinical signs of cervical myelopathy. OBJECTIVES: To investigate whether various demographic, clinical, radiologic, and electrophysiological parameters could predict progression from clinically asymptomatic (preclinical) spondylotic cervical cord compression to symptomatic myelopathy. SUMMARY OF BACKGROUND DATA: The data available on the prediction of the outcome in surgical and conservative treatment of spondylotic cervical myelopathy are controversial. Little is known about the clinical natural history of asymptomatic magnetic resonance image-detected spondylotic cervical cord compression and/or changes of signal intensity. METHODS: A group of 66 patients (32 women, 34 men, median age 50 years) with magnetic resonance signs of spondylotic cervical cord compression but without clear clinical signs of myelopathy was followed prospectively for at least 2 years (range, 2-8 years; median, 4 years). Various demographic, clinical, imaging, and electrophysiological parameters were correlated with clinical outcome. RESULTS: Clinical signs of myelopathy during the follow-up period were detected in 13 patients (19.7%). The only variables significantly associated with the development of clinically symptomatic spondylotic cervical myelopathy (SCM) were the presence of symptomatic cervical radiculopathy, electromyographic signs of anterior horn lesion, and abnormal somatosensory-evoked potentials. A multivariate logistic regression model based on these variables correctly classified 90% of cases into 2 subgroups: a group with development of symptomatic SCM and that without clinical manifestation of subclinical cervical cord compression. CONCLUSIONS: Electrophysiological abnormalities together with clinical signs of cervical radiculopathy could predict clinical manifestation of preclinical spondylotic cervical cord compression.

Approaches to spondylotic cervical myelopathy: conservative versus surgical results in a 3-year follow-up study.

STUDY DESIGN: A 3-year prospective randomized study was conducted. OBJECTIVE: To compare conservative and operative treatments of mild and moderate, nonprogressive, and slowly progressive forms of spondylotic cervical myelopathy. SUMMARY OF BACKGROUND: DATA It is not known whether the results of decompressive surgery for the mild and moderate forms of spondylotic cervical myelopathy are any better than those of the conservative approach. METHODS: For this study, 68 patients were randomized into two groups. Group A, treated conservatively, consisted of 35 subjects, whereas Group B, treated surgically, was composed of 33 patients. The clinical outcome was evaluated by modified JOA score, timed 10-m walk, the score for daily activities recorded by video and evaluated by two observers blinded to the type of therapy, and subjective assessment by the patients themselves at months 6, 12, 24, and 36 of the follow-up period. RESULTS: There was, on the average, no significant deterioration in mJOA score in the two groups over the 3-year follow-up period, but there was a slightly expressed decrease in the self-evaluation score in Group B, and a slight deterioration of the score for daily activities in Group A. Comparison of the two groups showed a significant difference in the timed 10-m walk test favoring group A, but no difference in mJOA score or self-evaluation by the patients themselves, with the exception of a better score at month 6 in favor of Group B. CONCLUSIONS: The 3-year follow-up study did not show, on the average, that the surgery is superior to conservative treatment for mild and moderate forms of spondylotic cervical myelopathy.