Development of an ultrasound score (US20BR) with small, medium, and large joints: a cross-sectional study in rheumatoid arthritis

Abstract Objectives To identify joint recesses with the strongest correlations between ultrasonographic and clinical variables to develop a Brazilian ultrasound-based joint score(USBR Score) for rheumatoid arthritis(RA) patients. Methods A cross-sectional study was conducted. Small, medium, and large joints recesses [60 (30 bilateral)] were assessed. Sonographic measuremants: Quantitative and semi-quantitative synovitis, power Doppler and bone erosion. Upper limb joint recesses: shoulders, elbows, wrists, metacarpophalangeals[dorsal(d)/palmar(p)], proximal interphalangeals. Lower limb joint recesses: hips, knees, ankles and metatarsophalangeals. Clinical variables: DAS-28, CDAI, SDAI, HAQ, morning stiffness, erythrocyte sedimentation rate, visual analogue scale (0–10 cm) of pain and swelling. Recesses with strongest correlations between ultrasonographic and clinical variables (highest Pearson correlation coefficients; p < 0.05) were selected to the score. Results Fifty-nine RA patients were evaluated [44 women; 74.6%; mean age 46.50 (9.28 years)]. 3,540 joint recesses and 14,160 ultrasound measurements were analyzed. Ultrasonographic correlations: Quantitative synovitis = 129(R 0.284–0.508); power Doppler = 101(R 0.252–0.569); Semi-quantitative synovitis = 86(R 0.256–0.460); and Bone Erosion = 48(R 0.184–0.381). Recesses with the highest correlations[10(20 per patient)] in descending order: wrists, 5th metacarpophalangeal(d/p), 1st metatarsophalangeal, 1st metacarpophalangeal(d), 4th metacarpophalangeal(d), 2nd metacarpophalangeal(d), 3rd metacarpophalangeal(d/p) and 3rd proximal interphalangeal, ankle and 5th metatarsophalangeal. Quantitative synovitis and power Doppler were selected for inclusion in the score (higher number and stronger statistical correlations), whereas semi-quantitative synovitis and bone erosion were excluded (lower number and weaker statistical correlations). Conclusions The Ultrasonographic variable included in the Brazilian ultrasound-based score for RA patients is power Doppler due its practicality. The joints indicated to the SCORE US20BR (BR for Brazil) were the following: wrists, 1st − 5th metacarpophalangeals, 3rd proximal interphalangeals, ankles, 1st and 5th metatarsophalangeals. The US20BR Score may optimize the ultrasound assessment of patients with RA.