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Background: Degenerative cervical spinal cord compression is becoming increasingly prevalent, yet the MRI criteria that define compression are vague, and vary between studies. This contribution addresses the detection of compression by means of the Spinal Cord Toolbox and assesses the variability of the morphometric parameters extracted with it. Methods: Prospective cross-sectional study. Two types of MRI examination, 3 and 1.5 T, were performed on 66 healthy controls and 118 participants with cervical spinal cord compression. Morphometric parameters from 3T MRI obtained by Spinal Cord Toolbox (cross-sectional area, solidity, compressive ratio, torsion) were combined in multivariate logistic regression models with the outcome (binary dependent variable) being the presence of compression determined by two radiologists. Inter-trial (between 3 and 1.5 T) and inter-rater (three expert raters and SCT) variability of morphometric parameters were assessed in a subset of 35 controls and 30 participants with compression. Results: The logistic model combining compressive ratio, cross-sectional area, solidity, torsion and one binary indicator, whether or not the compression was set at level C6/7, demonstrated outstanding compression detection (area under curve =0.947). The single best cut-off for predicted probability calculated using a multiple regression equation was 0.451, with a sensitivity of 87.3% and a specificity of 90.2%. The inter-trial variability was better in Spinal Cord Toolbox (intraclass correlation coefficient was 0.858 for compressive ratio and 0.735 for cross-sectional area) compared to expert raters (mean coefficient for three expert raters was 0.722 for compressive ratio and 0.486 for cross-sectional area). The analysis of inter-rater variability demonstrated general agreement between SCT and three expert raters, as the correlations between SCT and raters were generally similar to those of the raters between one another. Conclusions: This study demonstrates successful semi-automated compression detection based on four parameters. The inter-trial variability of parameters established through two MRI examinations was conclusively better for Spinal Cord Toolbox compared with that of three experts’ manual ratings.

BACKGROUND AND PURPOSE Non-myelopathic degenerative cervical spinal cord compression (NMDC) frequently occurs throughout aging and may progress to potentially irreversible degenerative cervical myelopathy (DCM). Whereas standard clinical magnetic resonance imaging (MRI) and electrophysiological measures assess compression severity and neurological dysfunction, respectively, underlying microstructural deficits still have to be established in NMDC and DCM patients. The study aims to establish tract-specific diffusion MRI markers of electrophysiological deficits to predict the progression of asymptomatic NMDC to symptomatic DCM. METHODS High-resolution 3 T diffusion MRI was acquired for 103 NMDC and 21 DCM patients compared to 60 healthy controls to reveal diffusion alterations and relationships between tract-specific diffusion metrics and corresponding electrophysiological measures and compression severity. Relationship between the degree of DCM disability, assessed by the modified Japanese Orthopaedic Association scale, and tract-specific microstructural changes in DCM patients was also explored. RESULTS The study identified diffusion-derived abnormalities in the gray matter, dorsal and lateral tracts congruent with trans-synaptic degeneration and demyelination in chronic degenerative spinal cord compression with more profound alterations in DCM than NMDC. Diffusion metrics were affected in the C3-6 area as well as above the compression level at C3 with more profound rostral deficits in DCM than NMDC. Alterations in lateral motor and dorsal sensory tracts correlated with motor and sensory evoked potentials, respectively, whereas electromyography outcomes corresponded with gray matter microstructure. DCM disability corresponded with microstructure alteration in lateral columns. CONCLUSIONS Outcomes imply the necessity of high-resolution tract-specific diffusion MRI for monitoring degenerative spinal pathology in longitudinal studies.

Background Cervical vertigo (CV) is a grossly over-diagnosed entity although, in all probability, it does not exist. The aim of this study was to test following hypothesis: that even in patients with one of the most severe forms of cervical spondylosis, degenerative cervical myelopathy (DCM), stimulation of the cervical proprioceptors does not provoke or increase vertigo Methods The study was performed in a cohort of 38 patients with DCM confirmed by clinical manifestation and MRI-detected degenerative cervical cord compression. The incidental presence of vertigo in these patients was investigated by means of a questionnaire and a clinical neurological examination. The cervical torsion test (to stimulate cervical proprioceptors), and ultrasound examinations of the extracerebral carotid and vertebral arteries (to exclude impaired blood circulation in the cervical region) were performed. All patients with vertigo underwent a diagnostic work-up designed to reveal its cause. Results: Subjective symptoms of vertigo occurring in the six months previous to examination were reported by 18 patients (47%). None of these patients responded positively to the cervical torsion test, while highly probable explanations involving an etiology for vertigo other than from the cervical region were found in all patients suffering from it. No patient exhibited significant stenosis of the vertebral arteries. Conclusions: There were no clear signs of CV in the cohort of patients with DCM. If patients with cervical spondylosis suffer from vertigo, its cause may, more easily be explained by common and treatable etiologies that do not lie in the cervical region.

Previous studies have yielded conflicting data concerning the value of evoked potential parameters in the assessment of clinical relevance of cervical cord compression in clinically “silent” cases. The aim of this study was to assess the value of somatosensory (SEP) and motor evoked potentials (MEP) in the evaluation and prediction of the clinical course, by means of a 2-year follow-up prospective electrophysiological and clinical study performed in patients with clinically “silent” spondylotic cervical cord compression. Thirty patients with MR signs of spondylotic cervical cord compression but without clinical signs of myelopathy were evaluated clinically and using SEPs and MEPs during a 2-year period. The results of the study showed that SEPs and MEPs documented subclinical involvement of cervical cord in 50% of patients with clinically “silent” spondylotic cervical cord compression. During the 2-year period clinical signs of cervical myelopathy were observed in one-third of patients with entry EP abnormality in comparison with no patients with normal EP tests. Combined SEPs and MEPs proved to be a valuable tool in the assessment of the functional relevance of subclinical spondylotic cervical cord compression. Normal EP findings predict a favourable 2-year clinical outcome.

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.

International audience; 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, we now 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 3 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 versus 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.

A prospective randomised 2-year study was performed to compare the conservative and operative treatment of mild and moderate forms of spondylotic cervical myelopathy (SCM). Forty-eight patients presenting with the clinical syndrome of SCM, with a modified Japanese Orthopaedic Association (mJOA) score of 12 points or more, were randomised into two groups. Group A, treated conservatively, consisted of 27 patients, mean age 55.6 +/- 8.6 years, while group B was treated surgically (21 patients, mean age 52.7 +/- 8.1 years). The clinical outcome was measured by the mJOA score, recovery rate (RR), timed 10 m walk, score of daily activities (recorded by video and evaluated by two observers blinded to the therapy), and by the subjective assessment of the patients at 6, 12, and 24 months of the follow-up. There was, on average, no significant deterioration in mJOA score, recovery ratio, or timed 10 m walk within either group during the 2 years of follow-up. In the surgery group there was a slight decline in the scores for daily activities and subjective evaluation. A comparison of the two groups showed no significant differences in changes over time in mJOA score or quantified gait, but there were significant differences in the score of daily activities recorded by video at 24 months, which was a little lower in the surgical group, and also in RR and subjective evaluation, which were both worse in the surgical group at months 12 and 24. However, at month 6, this last parameter was significantly better in the surgical than in conservative group. Surgical treatment of mild and moderate forms of SCM in the present study design, comprising the patients with no or very slow, insidious progression and a relatively long duration of symptoms, did not show better results than conservative treatment over the 2-year follow-up.