Metacarpophalangeal and wrist MRI bone marrow edema can reflect the disease activity of rheumatoid arthritis and correlate with SDAI, CDAI and DAS28

This study aims to investigate the value of Magnetic Resonance Imaging (MRI) in detecting Bone Marrow Edema (BME) in the Metacarpophalangeal (MCP) and wrist joints for Rheumatoid Arthritis (RA) and the correlation between the degree of BME and the disease activity of RA. Nonenhanced MRI scan of dominant wrist/metacarpophalangeal joints of 60 active RA patients were scored for BME using 0.2 T extremity-MRI. The correlation between the BME scores and the disease active index (DAS28, CDAI and SDAI), Rheumatoid Factor (RF) and anti-Cyclic Cirullinated Peptide antibodies (CCP) were assessed. The intra-observer agreement was moderate to excellent, with weighted kappa ranging from 0.88 to 1.0 and 0.79 to 1.0, respectively, while the interobserver agreement ranged from 0.64 to 0.79. MRI BME of MCP and wrist joints was found in 90% RA patients. SDAI (r=0.759, P <0.01), CDAI (r=0.682, P <0.01), and DAS28 (r=0.683, P <0.01) correlated well with BME scores. No significant correlations between BME scores and RF (r=0.138, P >0.05) or anti-CCP (r=0.083, P >0.05) were existed. Metacarpophalangeal and wrist joints BME existed in a higher frequency in active RA patients by using MRI examination indicated a higher sensitivity of this method and can be used as an image indice to monitor the disease activity of RA patients.