Background Patients with rheumatoid arthritis (RA) who have achieved clinical remission (CR) or low disease activity (LDA) may have synovitis detectable by ultrasound (US) and continue to get joint distruction. Despite an essential role for RA patients stability and mobility, the ankle joints are frequently omitted in activity scoring systems including DAS 28. Consequently patients with DAS 28 CR or LDA frequently maintain a symptomatic ankle and only few studies have assessed pathologies detected by ultrasonography in these circumstances.
Objectives The main purpose of the study was to evaluate the ankle joint involvement through power Doppler ultrasound in patients with RA who have achieved CR or LDA according to DAS 28 EULAR criteria.
Methods 50 consecutive RA patients (ACR/EULAR classification criteria 2010) who have achieved CR or LDA were reviewed. Patients underwent DAS28 assessment and US of the ankle joints. Synovitis was detected by power Doppler (PDUS) and scored on a 0–3 semi-quantitative scale. A total number of 100 ankle joints were examined using MSUS. Talonavicular, intertarsal- and tarso-metatarsal joints as well as flexor and extensor tendons were investigated.
Results Ankle pain was recorded in 31 patients while 19 patients were asymptomatic. Pathology detected was arthritis of the tibiotalar and/or talonavicular joint in 72% of the patients (36 out of 50), followed by tenosynovitis of the flexor tendons in 56% of the patients (28 out of 50). Gray scale findings were observed in 90.3% of the symptomatic patients (28/31) as well as in 53% of the asymptomatic patients (10/19) (p<0.01). PDUS activity was higher in symptomatic patients - 35% (11/31) compared to 21% in asymptomatic patients (4/19) (p<0.01). 10 patients (43%) in CR presented gray scale arthritis and tenosynovitis and 13% PD activity while 26 patients (93%) in LDA were positive for gray scale arthritis and tenosynovitis and 43% patients for PD signal.
Conclusions Ultrasonographic Doppler imaging reflects disease activity even in patients with low activity or in remission.Ankle joint is frequently involved according to ultrasound evaluation in patients with RA in DAS 28 LDA or CR. Most frequent pathologies detected by MSUS were arthritis of the tibiotalar and talonavicular joint, followed by tenosynovitis of the flexor tendons. Pathologic findings are also very common in asymptomatic patients with RA, whereas PDUS activity is predominately observed in symptomatic patients. Ankle joint should be more closely monitored for pathological findings in patients with LDA or CR as it frequently represents a source of pain, instability and disability in patients with RA.
Disclosure of Interest None declared