Background MRI-proven osteitis is known as the prognostic factor toward radiographic progression in patients with rheumatoid arthritis (RA). Musculoskeletal ultrasonography (MSKUS) is another high sensitive imaging modality to find joint injury of RA patients.
Objectives To explore whether musculoskeletal ultrasonography (MSKUS) assessment of synovial inflammation correlate with magnetic resonance imaging (MRI)-proven osteitis in patients with RA.
Methods Thirty RA patients who fulfilled 2010 RA classification criteria and were naïve to disease modifying anti-rheumatic drugs including biologics or glucocorticoids, were consecutively enrolled in this study. Patients gave their informed consent to be subjected to the protocol that was approved by the Institutional Review Board of Nagasaki University. Ten joints, both 2nd-5th metacarpophalangeal (MCP) and wrist joints, from each patient were examined by MSKUS and plain MRI within 3 days. Gray scale (GS) and power Doppler (PD) assessment of articular synovitis and bone erosion were examined by MSKUS in a semi-quantitative manner. Plain MRI-proven osteitis was also evaluated by OMERACT-RAMRIS score. The Spearman’s correlation coefficient test was used to investigate the correlation of each MSKUS finding with MRI-proven osteitis at the level of each joint.
Results Almost all patients had GS grade≧2 and/or PD grade≧2 articular synovitis on MSKUS in at least one joint. MSKUS-proven bone erosion was found at 30 sites and MRI-proven osteitis at 49 sites. These frequencies were higher in the wrist joints than in the MCP joints. Remarkable correlations were found between the GS grade (MCP joints; r=0.58, p < 0.0001, wrist joints; r=0.83, p<0.0001), PD grade (MCP joints; r=0.78, p < 0.0001, wrist joints; r=0.82, p<0.0001), presence of MSKUS-proven bone erosion (MCP joints; r=0.71, p < 0.0001, wrist joints; r=0.58, p<0.0001) and OMERACT-RAMRIS osteitis score.
Conclusions Our present data suggest that joint injury assessed by MSKUS correlates with MRI-proven osteitis in patients with RA, indicating that both imaging indices each other effectively point out the severity of joint inflammation in patients with RA.
References Kawashiri SY, et al. The power Doppler ultrasonography score from 24 synovial sites or 6 simplified synovial sites, including the metacarpophalangeal joints, reflects the clinical disease activity and level of serum biomarkers in patients with rheumatoid arthritis. Rheumatology (Oxford) 2011; 50: 962-5.
Kawashiri SY, et al. Musculoskeletal ultrasonography assists the diagnostic performance of the 2010 classification criteria for rheumatoid arthritis. Mod Rheumatol. 2013;23:36-43.
Disclosure of Interest None Declared