Objective: To evaluate the correlation between neurological deficits indicative of compressive myelopathy and MRI findings in a series of patients with RA and symptomatic involvement of the cervical spine.
Methods: Forty-one consecutive patients with RA were studied using cervical spine MRI. Unconditional logistic regression analysis was used to identify MRI parameters of cervical spine involvement associated with the development of neurological dysfunction.
Results: The mean age of the 41 patients (33 women and 8 men) was 59 yrs (range 23-82 yrs), while the median disease duration was 18 +/- 9 yrs (range 4-40 yrs). According to Ranawat's classification, 17 (42%) patients were in Class I, 21 (51%) in Class II and 3 (7%) in Class III. Thus, patients with clinical manifestations of compressive myelopathy (Ranawat's Class II + III) represented 58% (24/41) of all cases. Among the different MRI parameters of cervical spine involvement analysed, only the presence of atlantoaxial spinal canal stenosis [odds ratio (OR) 4.55; 95% CI 1.14-18.15], atlantoaxial cervical cord compression (OR 9.6; 95% CI 1.08-85.16) and subaxial myelopathy changes (OR 11.43; 95% CI 1.3-100.81) were associated with a significantly increased risk for neurological dysfunction (Ranawat's Class II or III).
Conclusion: In RA patients with symptomatic cervical spine involvement, there is a strong correlation between the development of neurological dysfunction and MRI identification of atlantoaxial spinal canal stenosis, especially in those cases with evidence of upper cervical cord or brainstem compression and subaxial myelopathy changes.