Development and Evaluation of a Novel Ultrasound Score for Large Joints in Rheumatoid Arthritis: One Year of Experience in Daily Clinical Practice

Objective. To introduce and evaluate a new standardized ultrasound (US) score developed for large joints in patients with rheumatoid arthritis (RA). Methods. A US score was designed to determine the degree of inflammation in the shoulder, the elbow, the hip, and the knee joint in patients with RA (Sonography of Large Joints in Rheumatology [SOLAR] score). Synovitis and synovial vascularity were scored semiquantitatively (grade 0-3) by gray-scale US (GSUS) and power Doppler US (PDUS). Patients with RA were examined at baseline and 3, 6, and 12 months after initiation of local or systemic therapy (disease-modifying antirheumatic drugs [DMARDs]/biologic agents). Erythrocyte sedimentation rate, anti-cyclic citrullinated peptide antibodies, and the clinical Disease Activity Score in 28 joints (DAS28) were determined. Results. A cohort of 199 patients were analyzed and followed up over 12 months. At baseline, before modification of the therapy, patients received either DMARDs (n = 131), DMARDs plus biologic agents (n = 46), biologic monotherapy (n = 8), or no DMARD therapy (n = 14). At baseline, the mean DAS28 score was 4.6 and decreased to 3.2 after 1 year of therapy (P < 0.001). All US scores demonstrated a statistically significant improvement except for the PDUS scores for the shoulder and the hip. In detail, the mean synovitis GSUS score for the knee decreased from 5.2 at baseline to 2.2 after 12 months of followup. The mean GSUS score for the shoulder fell from 2.6 to 1.6, for the elbow fell from 5.2 to 2.6, and for the hip fell from 2.2 to 0.4 (P < 0.05 for each). Conclusion. The SOLAR score is a feasible tool for the qualitative and quantitative evaluation of large joint involvement in patients with RA using US.