G. Supp

Dual-energy computed tomography compared with ultrasound in the diagnosis of gout

OBJECTIVES The aim of our study was to compare dual-energy CT (DECT) with US for the diagnosis of gouty arthritis and to correlate the imaging findings with results from synovial fluid aspiration whenever possible. METHODS We recruited 21 patients (17 male and 4 female) who presented with a clinical suspicion of acute or chronic gout in 37 joints. DECT scans of the hands, wrists, feet, ankles, knees and elbows were performed. For post-processing, a colour-coding gout software protocol was used. US examinations of the same joints were performed. In addition, joint fluid aspiration was performed in a total of 14 joints. RESULTS DECT images were positive for urate crystal deposits in 25 of 37 joints. US findings were positive in 24 of 37 examined joints. In 12 of 14 joints the synovial fluid aspiration was positive. CT and US findings correlated in 32 of 37 joints (86.5%; κ = 0.698, P < 0.001). CT and synovial fluid results correlated in 12 of 14 joints (85.7%; κ = 0.417, P = 0.119). US and cytology findings correlated in 14 of 14 joints (100%; κ = 1, P < 0.001). CONCLUSION DECT and US have comparable sensitivity for the detection of gouty arthritis in a clinical setting. However, DECT results should be interpreted carefully, as there could be some false-negative findings.

Sonographic Joint Assessment in Rheumatoid Arthritis: Associations With Clinical Joint Assessment During a State of Remission†

OBJECTIVE Sonography, as compared with clinical assessment, is a sensitive tool for evaluating synovitis in rheumatoid arthritis (RA). However, differences between these assessment tools may depend on how joint activity (i.e., an active joint) is defined. The present study was undertaken to compare clinically active joints with sonographically active joints in patients with RA, applying different sonographic definitions of an active joint. METHODS Sonographic assessment of the finger and wrist joints (total of 11 joints) of each hand was performed in RA patients whose disease was in remission (Clinical Disease Activity Index ≤2.8; n = 60). Gray-scale (GS) and power Doppler (PD) ultrasound signals for synovitis were evaluated on a 4-point scale (grade 0 = none, grade 3 = severe). The sensitivity and specificity of swollen joint counts were investigated using, as reference, increasingly stringent sonographic definitions of an active joint. Sonographic findings were also assessed for correlations with other clinical variables, including the Health Assessment Questionnaire (HAQ) disability index (DI). Followup analyses were performed after 6-12 months. RESULTS GS ultrasound signals yielded positive findings for synovitis in 67.2% of the 1,320 joints assessed, and PD ultrasound signals indicated signs of synovitis in 20.4% of the joints assessed. Clinical identification of joint swelling was 100% specific for sonographic joint activity, independent of the stringency of the sonographic definition used; maximum sensitivity of the swollen joint counts was 25% for the most stringent definition (i.e., GS grade 3 and PD grade 3). Furthermore, patients with a higher-grade PD signal (grade 3) showed a higher HAQ DI score compared to patients with lower-grade PD signals (mean ± SD HAQ DI 0.45 ± 0.62 versus 0.20 ± 0.35). A higher grade of PD signal at baseline was found in joints that were assessed as clinically swollen at the consecutive followup visit. CONCLUSION Low-grade PD and GS ultrasound signals may not necessarily reflect the presence of active synovitis in RA joints. High-grade PD signals correlate well with the presence of clinical joint swelling and clinical disease activity, and a higher grade of PD signal is associated with higher degrees of functional impairment.

Relationship between radiographic joint space narrowing, sonographic cartilage thickness and anatomy in rheumatoid arthritis and control joints.

Objective To validate ultrasound (US) for measuring metacarpal cartilage thickness (MCT), by comparing it with anatomical measurement using cadaver specimens. To correlate US MCT with radiographic joint space narrowing (JSN) or width (JSW) in patients with rheumatoid arthritis (RA). Methods Bilateral metacarpophalangeal (MCP) joints of 35 consecutive outpatients, with recent hand X-rays, were included in the analysis. Metacarpal and phalangeal cartilage of MCP 2–5 was assessed bilaterally by US. JSW and JSN were evaluated on X-rays by the van der Heijde modified Sharp method (vdHS). In addition, cadaver specimens of MCP 2–5 joints (n=19) were evaluated by anatomical measurement and US. Results The agreement (intraclass correlation coefficient) between sonographic and anatomical MCT on cadaver specimens of MCP joints was 0.61. MCT of individual MCP joints correlated with individual MCP JSN (r=−0.32, p<0.001) and individual MCP JSW (r=0.72, p<0.001). No correlation was found between phalangeal cartilage thickness and JSN in individual MCP joints. The US MCT summary score for MCP joints 2–5 correlated with summary scores for JSW (r=0.78, p<0.001), JSN (r=−0.5, p<0.001), erosion score of the vdHS (r=−0.39, p<0.001) and total vdHS (r=−0.47, p<0.001). Conclusions Sonographic cartilage assessment in MCPs is closely related to anatomical cartilage thickness. Both JSW and JSN by radiography represent cartilage thickness in the MCP joints of patients with RA quite well. Thus, US is a valid tool for measuring MCT if radiographs are not available or in case of joint malalignment.

Persistence of subclinical sonographic joint activity in rheumatoid arthritis in sustained clinical remission

Background Sonographic assessment, measuring grey scale (GS) and power Doppler (PD) signals, is a sensitive tool for the evaluation of inflammatory joint activity in patients with rheumatoid arthritis (RA). We evaluated the persistence of PD and GS signals in previously clinically active RA joints that have reached a state of continuous clinical inactivity. Methods We performed sonographic imaging of 22 joints of the hands of patients with RA, selected all joints without clinical activity but showing ongoing sonographic signs of inflammation, and evaluated the time from last clinical joint activity. Results A total of 90 patients with RA with 1980 assessed joints were included in this study. When comparing the mean time from clinical swelling, we found a significantly longer period of clinical inactivity in joints showing low sonographic activity (mean±SD time from swelling of 4.1±3.2 vs 3.1±2.9 years for PD1 vs PD≥2, p=0.031 and 4.5±3.4 vs 3.3±3.2 years for GS1 vs GS≥2, p≤0.0001). Conclusions We conclude that subclinical joint activity is long-lasting in RA joints in clinical remission, but attenuates over time. The latter conclusion is based on the observed shorter time duration from last clinical activity for strong compared with weaker sonographic signals.

The 2017 EULAR standardised procedures for ultrasound imaging in rheumatology

Background In 2001, the European League Against Rheumatism developed and disseminated the first guidelines for musculoskeletal (MS) ultrasound (US) in rheumatology. Fifteen years later, the dramatic expansion of new data on MSUS in the literature coupled with technological developments in US imaging has necessitated an update of these guidelines. Objectives To update the existing MSUS guidelines in rheumatology as well as to extend their scope to other anatomic structures relevant for rheumatology. Methods The project consisted of the following steps: (1) a systematic literature review of MSUS evaluable structures; (2) a Delphi survey among rheumatologist and radiologist experts in MSUS to select MS and non-MS anatomic structures evaluable by US that are relevant to rheumatology, to select abnormalities evaluable by US and to prioritise these pathologies for rheumatology and (3) a nominal group technique to achieve consensus on the US scanning procedures and to produce an electronic illustrated manual (ie, App of these procedures). Results Structures from nine MS and non-MS areas (ie, shoulder, elbow, wrist and hand, hip, knee, ankle and foot, peripheral nerves, salivary glands and vessels) were selected for MSUS in rheumatic and musculoskeletal diseases (RMD) and their detailed scanning procedures (ie, patient position, probe placement, scanning method and bony/other landmarks) were used to produce the App. In addition, US evaluable abnormalities present in RMD for each anatomic structure and their relevance for rheumatology were agreed on by the MSUS experts. Conclusions This task force has produced a consensus-based comprehensive and practical framework on standardised procedures for MSUS imaging in rheumatology.

The EULAR points to consider for health professionals undertaking musculoskeletal ultrasound for rheumatic and musculoskeletal diseases

Musculoskeletal ultrasound has evolved into an important clinical decision-making tool by assisting in the diagnosis of inflammatory arthritis, monitoring disease activity and therapeutic response, and guiding interventions.1–7 The role of the non-medical health professional has advanced, with many undertaking training and using musculoskeletal ultrasound to improve patient care and in doing so, increasing their scope of practice. Health professionals with clinical expertise and experience using ultrasound are also providing training for colleagues and medical clinicians. As previously described among rheumatologists,8 ,9 the use of musculoskeletal ultrasound and training undertaken varies significantly between different professional groups and across Europe. Guidelines to support training for rheumatologists have been formulated10 but currently there are no recommendations to support the education and training needs of non-medical health professionals using musculoskeletal ultrasound. A European League Against Rheumatism (EULAR) task force was established to reach a consensus on the role of, and education and training needs of health professionals undertaking musculoskeletal ultrasound for the management of people with …

Clinical joint inactivity predicts structural stability in patients with established rheumatoid arthritis

Objectives Clinical joint activity is a strong predictor of joint damage in rheumatoid arthritis (RA), but progression of damage might increase despite clinical inactivity of the respective joint (silent progression). The aim of this study was to evaluate the prevalence of silent joint progression, but particularly on the patient level and to investigate the duration of clinical inactivity as a marker for non-progression on the joint level. Methods 279 patients with RA with any radiographic progression over an observational period of 3–5 years were included. We obtained radiographic and clinical data of 22 hand/finger joints over a period of at least 3 years. Prevalence of silent progression and associations of clinical joint activity and radiographic progression were evaluated. Results 120 (43.0%) of the patients showed radiographic progression in at least one of their joints without any signs of clinical activity in that respective joint. In only 7 (5.8%) patients, such silent joint progression would go undetected, as the remainder had other joints with clinical activity, either with (n=84; 70.0%) or without (n=29; 24.2%) accompanying radiographic progression. Also, the risk of silent progression decreases with duration of clinical activity. Conclusions Silent progression of a joint without accompanying apparent clinical activity in any other joint of a patient was very rare, and would therefore be most likely detected by the assessment of the patient. Thus, full clinical remission is an excellent marker of structural stability in patients with RA, and the maintenance of this state reduces the risk of progression even further.

FRI0092 Influence of Temperature and Humidity on Disease Activity in Rheumatoid Arthritis

Objectives To evaluate whether meteorological parameters influence disease activity in patients with rheumatoid arthritis (RA). Methods We assessed correlations between individual meteorological variables and clinical measures of disease activity: clinical disease activity index (CDAI), self-reported pain (by visual analogue scale), tender- and swollen 28 joint counts (TJC and SJC). Assessments documented in our RA database as well as the average temperature and relative humidity, obtained from the Central Institute for Meteorology and Geodynamics, were matched on a daily basis for a period of 10 years between 2005 and 2015, and analyzed using generalized estimating equations (longitudinal data analysis). Results A total of 1437 patients with RA (average disease duration at first visit: 4.88±8.63 years; 77% female, mean CDAI 17.8±11.7, mean time in study: 75 month, mean number of visits during study period: 19) were analyzed. Higher temperature and lower humidity were significantly associated with lower CDAI (p=0.0002, and p=0.0332, respectively). Regarding pain, the effects of temperature showed an interaction with humidity: while lower temperatures were associated with higher pain levels at the low and middle tertile of relative humidity, they corresponded to a lower pain level at the high tertile of relative humidity. Temperature showed a significantly negative correlation with TJC (p<0.0001), while relative humidity showed a significantly positive correlation with SJC (p=0.0321). Similar to pain, there was again an interaction of temperature and humidity in the SJC analysis. Conclusions In this largest association study of meteorological parameters with RA specific outcomes both temperature and relative humidity were shown to have significant effects on disease activity. Individual measures of disease activity and pain correlated either with temperature or humidity, while the composite CDAI measure correlated with both meteorological variables. These aspects may have to be taken into account in longitudinal analyses of disease activity of RA. Disclosure of Interest None declared

Interphalangeal Osteoarthritis Radiographic Simplified (iOARS) score: a radiographic method to detect osteoarthritis of the interphalangeal finger joints based on its histopathological alterations

Objective To develop a radiographic score for assessment of hand osteoarthritis (OA) that is based on histopathological alterations of the distal (DIP) and proximal (PIP) interphalangeal joints. Methods DIP and PIP joints were obtained from corpses (n=40). Plain radiographies of these joints were taken. Joint samples were prepared for histological analysis; cartilage damage was graded according to the Mankin scoring system. A 2×2 Fishers exact test was applied to define those radiographic features most likely to be associated with histological alterations. Receiver operating characteristic curves were analysed to determine radiographic thresholds. Intraclass correlation coefficients (ICC) estimated intra- and inter-reader variability. Spearmans correlation was applied to examine the relationship between our score and histopathological changes. Differences between groups were determined by a Students t test. Results The Interphalangeal Osteoarthritis Radiographic Simplified (iOARS) score is presented. The score is based on histopathological changes of DIP and PIP joints and follows a simple dichotomy whether OA is present or not. The iOARS score relies on three equally ranked radiographic features (osteophytes, joint space narrowing and subchondral sclerosis). For both DIP and PIP joints, the presence of one x-ray features reflects interphalangeal OA. Sensitivity and specificity for DIP joints were 92.3% and 90.9%, respectively, and 75% and 100% for PIP joints. All readers were able to reproduce their own readings in DIP and PIP joints after 4 weeks. The overall agreement between the three readers was good; ICCs ranged from 0.945 to 0.586. Additionally, outcomes of the iOARS score in a hand OA cohort revealed a higher prevalence of interphalangeal joint OA compared with the Kellgren and Lawrence score. Conclusions The iOARS score is uniquely based on histopathological alterations of the interphalangeal joints in order to reliably determine OA of the DIP and PIP joints radiographically. Its high specificity and sensitivity together with the dichotomous approach renders the iOARS score reliable, fast to perform and easy to apply. This tool may not only be valuable in daily clinical practice but also in clinical and epidemiological trials.

Imaging Anatomy: Conventional Radiography

When Wilhelm Conrad Rontgen discovered X-rays in 1895, the first radiograph he took was of his wife’s hand (Rontgen, Sitzungsberichte der Physikalisch-medizinischen Gesellschaft zu Wurzburg 9:132–41, 1895). Conventional radiography has played a key role in musculoskeletal imaging ever since and is generally the first imaging modality performed in most rheumatic and musculoskeletal diseases. It is by far the most commonly performed imaging technique for depicting the skeletal system. Conventional radiographs may be diagnostic on their own or may provide relevant information, often complementing other imaging techniques, such as ultrasound (Isenberg and Renton, Oxford: Oxford University Press, 2003). A basic understanding of conventional radiography is therefore indispensable for rheumatologists and sonographers alike.