To compare the frequency of joint and tendon disease on ultrasound (US) and clinical examination, and to investigate agreement between US and clinical evaluation in ankles with clinically active juvenile idiopathic arthritis (JIA).
US and clinical evaluation were performed independently in the joint and tendon compartments of 105 ankles. Gray-scale (GS) US and power Doppler (PD) US joint abnormalities were scored on a 4-point semiquantitative scale. A joint with a GS score ≥2 and/or a PD score ≥1 was defined as active on US. Agreement was tested using kappa statistics.
A total of 163 joints in 89 ankles had active synovitis on US. The tibiotalar (TT) joint was the most commonly affected joint on US and on clinical evaluation. The intertarsal (IT) joint and the subtalar (ST) joint were the second in frequency on US and on clinical evaluation, respectively. Tenosynovitis was found more commonly on US than on clinical evaluation (70.5% and 32.4%, respectively), and was more frequent in the medial and lateral than in the anterior tendon compartment. Isolated tenosynovitis was detected on US in 12 of 105 ankles. Agreement between US and clinical evaluation for detection of active synovitis and tenosynovitis was less than acceptable (κ <0.4). No correlation was found between any feature of active disease recorded on clinical evaluation (joint swelling, tenderness/pain on motion, and restricted motion) and active synovitis on US in the TT joint, ST joint, and IT joint.
Coupling clinical evaluation with US aids in correctly localizing pathology. US training of practitioners is recommended to manage ankle disease in JIA.