Ankle Evaluation in Active Rheumatoid Arthritis by Ultrasound: A Cross-Sectional Study

Ankle joint evaluation is underestimated in many clinical and sonographic scores used for evaluation and follow-up of rheumatoid arthritis (RA) patients. Agreement on examination parameters is poor among sonographic scores that include the ankle joint. More effort is needed to detect the value of ankle joint examination in RA and assessment of ultrasonographic signs according to frequency, disease duration and activity. The objective of this study was to use ultrasound (US) to detect ankle involvement in active RA and to compare findings with disease duration, disease activity and assessment of ankle bone erosion. A total of 63 RA patients with active disease and 20 controls were included in the study. The tibiotalar and talonavicular joints were examined by US for synovitis and/or effusion in gray-scale and power Doppler modes. The anterior, lateral and posterior ankle tendons were examined for tenosynovitis and tendinosis. Mean age was 35.1 ± 8.3 y, mean disease duration was 22.7 ± 9.6 mo and the mean 28-joint Disease Activity Score-erythrocyte sedimentation rate was 3.05 ± 0.66. Ankle involvement was seen in 28 patients (44.4%). The most frequent pathologies detected were tenosynovitis (30.2%), followed by synovitis (18.3%), erosion (8.7%) and tendinosis (4%). The earliest sonographic signs were tenosynovitis, followed by synovitis, erosion and tendinosis. The right ankle exhibited greater involvement than the left ankle, which was significant with respect to erosions (p = 0.009). The most common tendon affected by tenosynovitis was the tibialis anterior (22.2%), followed by the tibialis posterior (20.6%). Tenosynovitis, especially of the tibialis anterior and posterior, tibiotalar synovitis and erosions should be considered in future US ankle scores for the assessment of RA.