Twenty patients with longstanding polyarticular rheu~ matoid arthritis (including knee involvement) were se~ lected for this study. The severity of the knee synovitis was assessed before and during treatment (with intraarticular corticosteroid injections) using clinical scores, sonography, and thermography. In all patients, the in· flammation regressed during treatment. During followup, the quantity of synovial fluid, as measured sonographically 10 days after the start of therapy, correlated Q uantification of pain and inflammation in rheumatoid arthritis is a difficult clinical problem; 1 as a result, any evaluation based on patient symptoms is fraught with error. A standardized and reproducible method of grading both the severity of disease and the response to treatment is sorely needed.1.2In the last 20 years, various methods have been proposed to assess the severity of articular involvement, including radioisotope scanningM and thermography.5-7 More recently, the use of sonography and magnetic resonance has been suggested. a-u The aim of the present study is to compare the utility of the sonographic parameters, synovial thickness and 7:561, 1988) intra-articular fluid, with the clinical and thermographic rating systems, 2.5;7 both before and during treatment of rheumatoid arthritis of the knee. MATERIALS AND METHODSSixteen women and four men aged 40 to 73 (mean 59 years) were included in this study. All patients had classical rheumatoid arthritis and were classified according to the grading system of the American Rheumatism As· sociation. u All patients had persistent and disabling knee symptoms despite control of the articular symptoms elsewhere by conventional drug therapy.The mean duration of the rheumatoid arthritis in our group was 10 years (range 2 to 26 years). The duration of the acute exacerbation of knee arthritis ranged between 8 and 52 weeks (mean 21 weeks).According to the rating system of the American Rheumatism Association, eight patients were in stage 1 and 12 were in stage 2. uThe patients were assessed on day 0 (before treatment) and at 10 days and three months after treatment