The characteristics of synovitis under energy Doppler ultrasonography in knee osteoarthritis patients / 中华风湿病学杂志

ABSTRACT

Objective To investigate the correlation between synovial inflammatory changes (synovial blood signals,synovial thickness,joint effusion) and cartilage injury,meniscus prominence of knee osteoarthritis (KOA) under energy Doppler ultrasound and further to assess the value of ultrasound for prognostic judgment in KOA.Methods A total of 291 KOA patients from our hospital from 2016 to 2018 were collected.The patients with rheumatoid arthritis (RA) with knee joints involved were recruited as control group.The data that conform to the normal distribution were expressed by mean±SD,and others were represented by M (P25,P75).The t test,the rank test and Chi-square test were used between the two groups,and ANOVA or K-W test was used to compare the data between the multiple groups,Spearman correlation analysis was used for correlation analysis.Results ① The proportion of synovial blood flow signal in KOA group was lower than RA group (19.6％ vs 47.7％,x2=286.2,P＜0.01),as well as the typical synovial thickness [2.6(0,3.95) mm vs 3.43 (1.85,6) mm,Z=-3.674,P＜0.01] and popliteal cyst (11.5％ vs 18.5％,x2=4.484,P=0.04).② In KOA group,no significant difference was found between ESR and hs-CRP among different synovial blood signals (H=7.213,H=0.883,all P＞0.05).ESR from KOA group were both significantly lower than controls but the synovial blood signals was the same except for power Doppler signal-2 group (Z=-8.414,Z=-4.991,t=-3.428,all P＜0.05);hs-CRP from KOA group were both significantly lower than controls but the synovial blood signals was the same.③ A total of 489 knee joints were detected in 291 patients with KOA,of which synovial blood flow signals were found in 96 joints,the power Doppler signal-I group was the most frequent in KOA (80/96,83.3％).In addition,joint effusion and synovial thickening were positively correlated with the synovial blood signals,(r=0.277,r=0.411,all P＜0.05).④ At last,the degrees of ultrasound blood flow signal in KOA group was positively associated with the WOMAC score,the Lequsne index and US-1 score (r=0.352,r=0.424,r=0.59,all P＜0.05).Conclusion Energy Doppler ultrasonography can be used to detect the KOA synovitis.Synovitis is not rare in KOA patients,and which is associated with disease activity.However,KOA and RA cannot be differentiated by energy Doppler ultrasonography.