Prospective evaluation of clinical and ultrasound findings in ankle disease in juvenile idiopathic arthritis: importance of ankle ultrasound.

OBJECTIVE: To prospectively compare clinical examination of the ankle structures with ultrasound (US) findings.
METHODS: In 42 children with juvenile idiopathic arthritis (JIA; 25 girls, 17 boys, mean age 11.3 yrs, range 2.3-22.3 yrs), a total of 61 swollen/painful ankles were assessed clinically and ultrasonographically. Accurate clinical examination of the entire ankle joint was performed, focusing especially on 3 regions - tibiotalar joint and medial and lateral tendons. Clinical and US findings were both scored 0-3 (normal-severe).
RESULTS: US demonstrated no signs of tibiotalar joint effusion in 14 out of 43 ankles considered clinically involved. For the medial tendons, US showed tenosynovitis in 13 ankles out of 31 thought to be clinically normal; and for the lateral tendons, of the 19 deemed to be clinically involved, less than 50% had involvement on US. Very poor agreement was observed comparing the clinical and US scores for the 3 regions: tibiotalar joint, kappa = 0.3; medial tendons, kappa = 0.24; lateral tendons, kappa = 0.25. With regard to other ankle structures, only 39% of the subtalar (talocalcaneal) joints considered clinically involved were deemed abnormal on US. Finally, of the 10 ankles with talonavicular US effusion, only 2 were considered clinically involved.
CONCLUSION: Using US findings as the "gold standard," clinical examination of the ankle in children with JIA was found to be inadequate in identifying the structures involved. US assessment prior to any glucocorticoid injection should be considered to improve the outcome. A prospective study comparing the outcome following clinical- versus US-guided ankle joint injection should be undertaken, to confirm our findings.