Prediction of Erosive Disease in Early Rheumatoid Arthritis (RA) by Ultrasound and Cartilage Biodegradation Markers

Multicenter, prospective, open-label, cohort study. Primary objective: Determination of the predictive value of US alone and in combination with cartilage biodegradation markers on radiographic progression (change in Ratingen score) Secondary objectives: * Correlation of ultrasound synovitis score and clinical disease activity score * Determination of the sensitivity of ultrasound erosion detection compared to MRI * Assessment of the value of including tenosynovitis assessment for predicting radiographic progression * Assessment of the predictive value of ultrasound synovitis score at baseline for the need to install biologic DMARDs