OBJECTIVES: To answer the question whether cervical spondylosis would increase the incidence of cord lesions in MS patients, we investigated the statistical association between the two pathologies.

METHODS: We extracted demographics, basic disease characteristics and MRI data of a cohort of 304 consecutive MS patients. For a subset of 176 patients, a detailed analysis independently assessed for each cervical level the co-existence of spinal canal narrowing from spondylosis and corresponding cord signal abnormalities.

RESULTS: The cohort had typical demographics and in over 80 % of cases there was at least one cord lesion. EDSS correlated with age, disease duration, cerebral lesion burden and spinal cord lesions. After adjusting for either age, disease duration, central lesion burden, or EDSS, the presence of spinal spondylosis was not significantly associated with spinal cord lesions (p > 0.05). In the subset of 176 subjects with the level-by-level spine data, we found a highly statistically significant association (Pearson's chi(2) = 23.7, p < 0.001) between canal narrowing and cord lesion at the level directly above or below. This association remained highly significant in both univariable and multivariable logistic regression models adjusting for age, disease duration, MS treatment, cerebral lesion burden and disability scores (p < 0.001).

CONCLUSIONS: The data from our cohort of MS patients suggest an indirect contribution of cervical spondylosis to disability by increasing the risk of developing localized cord lesions. While further studies are needed to confirm the findings and clarify disease mechanisms, closer attention should be paid to worsening spondylosis in patients with MS.