Spinal mobility in the cervical and lumbar spine correlates with magnetic resonance imaging findings for inflammatory and structural changes in patients with active ankylosing spondylitis.

OBJECTIVES

We aimed to assess relationships between single Bath Ankylosing Spondylitis Metrology Index (BASMI) components and corresponding spinal segment magnetic resonance images (MRI) in anti-tumour-necrosis-factor-treated AS patients.

METHODS

Using available MRI and BASMI data from the GO-RAISE trial (n=91 patients), MRI scores for active inflammatory (ASspiMRI-a) and chronic structural (ASspiMRI-c) changes in cervical and lumbar spine segments were compared with BASMI cervical (cervical-rotation [CR] angle, tragus-to-wall [TTW] distance) and lumbar (lumbar flexion [LF], lateral-lumbar-flexion [LLF]) spine component scores (linear definition). Generalised linear models were employed to assess relationships between BASMI components and ASspiMRI-a/ASspiMRI-c measurements at baseline and for week-14 (golimumab/placebo groups) and week-104 (all golimumab-treated) change scores.

RESULTS

Baseline lumbar ASspiMRI-a scores correlated with LF and LLF (β=0.231 and 0.238, respectively; both p<0.01), while this was less prominent for ASspiMRI-c scores and LLF (β=0.142, p=0.04). A significant but weak correlation was found between changes from baseline to week 104 in cervical spine ASspiMRI-c score and TTW distance among all treated patients (β=0.161, p=0.003).

CONCLUSIONS

Detailed assessments indicated baseline spinal mobility impairment in patients with active AS correlated weakly with MRI-detected lumbar spinal inflammation; correlations with chronic, structural damage/changes were very weak. Improved, less variable MRI and spinal metrology assessments are needed for future clinical research.