Paediatric and Adolescent Rheumatology [143–150]

• Published in: Rheumatology (Oxford, England) Vol. 49; no. suppl-1; pp. i86 - i89
• Main Authors: Pascoli, Laura, Napier, Noel J., Wray, Maria, Mc Carron, Maura, Mc Allister, Catherine, Rooney, Madeleine E., Gibson, David S., McAlilister, Catherine, Scaife, Caitriona, Dunn, Michael, Pennington, Stephen, Rooney, Madeleine, Wright, Stephen, Hinks, Anne, Martin, Paul, Flynn, Edward, Eyre, Steve, Packham, Jon, Barton, Anne, Worthington, Jane, Thomson, Wendy, McErlane, Flora, Kulkarni, Priyanka, Nicholl, Karl, Foster, Helen E., Pain, Clare, Baildam, Eileen, Foster, Helen, Harrison, Mark, Symmonds, Deborah
• Format: Journal Article
• Language: English
• Published: Oxford University Press 01.04.2010
• ISSN: 1462-0324; 1462-0332
• DOI: 10.1093/rheumatology/keq724

Background: We prospectively compared agreement between clinical, ultrasound (US) and MRI assessments of the knee joints in children with juvenile idiopathic arthritis (JIA). Methods: Three hundred and thirty one knees from 48 children over a period of 2 years, affected by JIA with knee arthritis, were assessed clinically and ultrasonographically on the same day, using a semi-quantitative scoring system from 0 to 3 (0: normal; 1: mild; 2: moderate; 3: marked) for swelling and effusion, respectively. A subgroup of these children (25) with a total of 40 knees had matching MRI scans obtained within 0 to 14 days from clinical and US examinations. For those, US and MRI scans (T1 weighted images) were scored 0-3 for effusion, synovial hypertrophy, bone oedema and bone erosions, using for the first time our newly developed knee MRI scoring system. Results: A moderate agreement for effusion was found between the 331 knees assessed clinically and ultrasonographically (linear weighted Kappa: 0.54). Out of the 260 clinical normal knees, 30 (11.5%) had mild to moderate effusion on US and 89 (34.2%) had trace of effusion. In the subgroup of 40 knees that had matching US and MRI scans it was demonstrated a good agreement for effusion (linear weighted Kappa: 0.66) and a moderate agreement for synovial hypertrophy (linear weighted Kappa: 0.47). The inter-observer US agreement was very good for effusion (linear weighted kappa: 0.87) and good for synovial hypertrophy (linear weighted kappa: 0.68). The intra-observer MRI agreement was good for effusion (linear weighted kappa: 0.73) and very good for synovial hypertrophy (linear weighted kappa: 0.85). Conclusions: A significant number of knee joint effusions are missed on clinical examination. Musculoskeletal US is a simple, cheap, non invasive, rapid and effective method of detecting joint synovitis in JIA and should be used: as an adjunct to clinical examination especially when joint injections are being considered and to avoid under-diagnosis; when clinical examination is negative and symptoms are equivocal for active arthritis; to identify the site for the intra-articular injection; at follow-up to assess treatment’s efficacy. In our experience it is also very well tolerated by children. Normal data on Paediatric knees are needed to demonstrate whether a small amount of synovial fluid is present. Comparison between clinical and US scores (0-3) for swelling and effusion respectively US EFFUSION SCORE CLINICAL SWELLING SCORE 0 1 2 3 0 230 5 0 0 1 25 27 7 0 2 5 2 12 8 3 0 0 3 7 Disclosure statement: All authors have declared no conflicts of interest.