Magnetic resonance imaging findings in 84 patients with early rheumatoid arthritis: bone marrow oedema predicts erosive progression.

OBJECTIVES

To examine the spectrum and severity of magnetic resonance imaging (MRI) findings in patients with early rheumatoid arthritis (RA), and to investigate the predictive value of MRI findings for subsequent development of conventional radiographic (CR) damage and MRI erosions.

METHODS

84 consecutive patients with RA with disease duration <1 year were enrolled. Patients were treated according to standard clinical practice, and evaluated at baseline, 3, 6 and 12 months by core measures of disease activity, conventional radiographs of both hands and wrists and MRI of the dominant wrist. MR images were scored according to the OMERACT rheumatoid arthritis magnetic resonance imaging score (RAMRIS), and conventional radiographs according to the van der Heijde modified Sharp score.

RESULTS

MRI findings reflecting inflammation (synovitis, bone marrow oedema and tenosynovitis) decreased during follow-up, while there was a small increase in MRI erosion score and CR damage. The proportion of patients with erosive progression at 1 year was 48% for conventional radiography and 66% for MRI. Baseline MRI bone marrow oedema (score >2 RAMRIS units) was identified as an independent predictor of both CR (odds ratio = 2.77 (95% confidence interval (CI) 1.06 to 7.21)) and MRI erosive progression (B = 0.21 (95% CI 0.08 to 0.34)).

CONCLUSIONS

MRI findings were common in early RA, and MRI bone marrow oedema was an independent predictor of radiographic damage. These results suggest that MRI scans of the dominant wrist may help clinicians to determine which patients need early and aggressive treatment to avoid subsequent joint damage.