OBJECTIVES:A systematic literature review (SLR) of publications from 2000 to 2022 identified terminology for calcium pyrophosphate crystal deposition (CPPD) and revealed substantial heterogeneity and poor adherence to recommendations. This study aimed to standardise CPPD terminology by developing an international consensus on labels and definitions. METHODS:Members of the Gout, Hyperuricemia and Crystal-Associated Disease Network (G-CAN) were invited by email to participate in a 3-round Delphi exercise. A steering committee identified key components of CPPD aetiology, pathophysiology, and clinical presentation among elements appearing in >10% of SLR papers, adding or removing items when scientifically justified. Participants selected preferred labels for each element. Respondents to the first round were invited to subsequent rounds. This paper reports the resulting G-CAN CPPD nomenclature. RESULTS:Consensus was reached for 'calcium pyrophosphate (CPP) crystal' and 'calcium pyrophosphate crystal deposition (CPPD)' to describe the deposition process. The unified term 'calcium pyrophosphate crystal deposition on imaging' was adopted across imaging modalities, whereas 'chondrocalcinosis' was redefined as conventional radiographic cartilage calcification consistent with CPPD. Four clinical manifestations were identified: 'acute CPP crystal arthritis' (with 'flare' for acute episodes), 'chronic CPP crystal arthritis', 'crowned dens syndrome', and 'osteoarthritis with CPPD'; the term 'pseudogout' received no support. The condition is now classified as 'asymptomatic CPPD' or 'CPPD disease' for symptomatic presentations. CONCLUSIONS:This G-CAN nomenclature is the first systematic effort to align CPPD terminology with contemporary biological and imaging evidence. By resolving longstanding ambiguities-particularly regarding 'chondrocalcinosis'-it provides a framework for consistent research definitions, clinical trial homogeneity, and improved patient care.

OBJECTIVE:This study tested the reliability of an ultrasound scoring system (0-3) for lacrimal glands using an OMERACT semi-quantitative ultrasound scoring system developed for salivary glands in primary Sjögrens Disease pSjD). METHODS:Fourteen rheumatologists participated in a static image exercise on ultrasound images in order to evaluate the reliability of the existing salivary gland ultrasound (SGUS) scoring system when applied to lacrimal glands. All images were obtained from patients with suspected pSjD using a 6-24 MHz linear hockey stick transducer. One hundred images representing different grades of parenchyma changes in the lacrimal glands were collected for the inter-observer analyses and 32 of these were repeated to assess intra-observer reliability. Kappa statistics were applied. RESULTS:Participants had musculoskeletal ultrasound experience ranging from 2-28 years, and SGUS experience from 0-12 years. The majority (11/14) had no prior experience in lacrimal gland ultrasound but 13/14 had experience in SGUS. Intra-observer reliability was good to excellent, with kappa values ranging from 0.63 to 1.00 (95% CI: 0.77-0.89). Inter-observer reliability showed good agreement, with a kappa of 0.63 (95% CI: 0.61-0.65). CONCLUSION:The consensus-based semi-quantitative ultrasound scoring system for salivary glands showed good to excellent intra-observer and good inter-observer reliability when applied to the lacrimal glands using static images. The next step is to assess the reliability when scoring lacrimal glands in video-clips and in live exercises.

AIM:Current ultrasound grading tools do not fulfil the criteria of the OMERACT Filter 2.1 Instrument Selection Algorithm (OFISA)and are not idiopathic inflammatory myopathies (IIM)-specific, prompting further work by the OMERACT US Working Group. The aim of this study was, therefore, to develop consensual definitions of elementary US lesions specific to IIM, using a structured methodological approach. METHODS:A multicentre group of 21 international experts from the OMERACT US in myositis subgroup participated in a multi-round Delphi survey followed by a web-based reliability exercise. RESULTS:The group participated in five Delphi rounds, followed by a web-based reliability exercise. Preliminary broad domains of "inflammation" and "damage" resulted in substantial intra-rater reliability testing (kappa: 0.662 and 0.620, respectively) but poor inter-rater reliability testing (kappa: 0.142 and 0.112, respectively). A further two Delphi rounds resulted in a consensus to revise the broad domains to a single domain of "muscle inflammation and damage", with elementary components including echogenicity and fascial thickness. A categorical morphological grading system was then tested in a web-based reliability exercise, which resulted in substantial intra-rater reliability testing (kappa: 0.706, min: 0.051, max: 1.000, SD: 0.295) and an improved moderate inter-rater reliability testing (kappa: 0.506, min: 0.421, max: 1.000, SD: 0.167). CONCLUSION:The systematic approach by the OMERACT US in the myositis subgroup has developed a categorical morphological scoring system, which showed moderate inter-rater reliability using consensus-derived definitions of US domains in IIM.

BACKGROUND:Osteoarthritis (OA) is a leading cause of chronic pain and functional impairment, associated with persistent inflammation, potentially due to impaired resolution. Specialized pro-resolving lipid mediators (SPMs) regulate inflammation resolution and restore homeostasis. The GAUDI study previously demonstrated that SPM supplementation reduces pain and improves quality of life (QoL) in patients with knee OA. This analysis assesses the impact of SPM supplementation on inflammatory biomarkers (IB) and SPM levels and their relationship with clinical outcomes. METHODS:This is a secondary analysis of the GAUDI trial, a randomized, multicenter, double-blind, placebo-controlled study conducted in Spain in adults with symptomatic knee OA who received daily supplementation with SPMs or placebo for 12 weeks. Endpoints included changes in plasma IB and SPM levels and their correlation with clinical outcomes. RESULTS:Changes in IL-1 (15.9 vs. -1.1 pg/ml, p-value: 0.051) and IL-18 (10.3 vs. -1.4 pg/ml, p-value: 0.29) showed a tendency toward reduction in the SPM group compared to the placebo group. Changes in IL-1 and IL-8 positively correlated (r = 0.707, p-value: 0.005 and r = 0.551, p-value: 0.04; respectively) with changes in WOMAC score and negatively correlated (r = -0.797, p-value <0.001 and r = -0.804, p-value <0.001; respectively) with changes in EuroQoL-5 VAS score. Changes in IL-1 (r = 0.554, p-value: 0.048) and IL-6 (r = 0.631, p-value: 0.014 and r = 0.572, p-value: 0.031) correlated with changes in OMERACT-OARSI pain score. No significant differences in IB levels were observed between groups during the intervention. Minor changes in SPM levels point to metabolic pathways at work with SPM supplementation. In patients with a BMI ≥25 kg/m², most IB tended to decrease following SPM consumption. CONCLUSIONS:This analysis suggests a potential association between SPM supplementation, decreased inflammation, and improved pain and QoL in patients with knee OA. Subtle changes in blood plasma SPM levels were detected that indicate, through bioinformatics analysis, a pathway-specific metabolome activation induced by SPM supplementation. TRIAL REGISTRATION:NCT05633849. Registered December 1st, 2022. Retrospectively registered, https://clinicaltrials.gov/ct2/show/study/NCT05633849.

OBJECTIVES:This study aimed to develop consensual definitions and semiquantitative scoring for structural damage on ultrasound and to test the reliability of individual components of a global Outcome Measures in Rheumatology ultrasound joint damage score (GLODS) in rheumatoid arthritis (RA). METHODS:A Delphi survey including statements on normal ultrasound appearance of joint features, scanning technique, new definitions, and scoring systems for 3 components of structural damage (bone erosions, cartilage change, and joint malalignment) was circulated among task force members. After agreement (≥75% of grades 4-5 on a 1-5 Likert scale) was achieved on the statements, datasets of ultrasound images representing various grades of the above-mentioned structural damage components were created and used in 2 web-based exercises. Finally, the metacarpophalangeal joints 1 to 5 of 7 patients with RA were scanned with ultrasound, twice on the same day by 7 task force members for detecting and scoring the 3 components using the consensus-based semiquantitative GLODS. Intraobserver and interobserver reliability of the new scoring system was measured by weighted kappa. RESULTS:Agreement on a total of 9 statements was reached in 4 Delphi rounds. Intraobserver and interobserver reliability for the individual components ranged from good to excellent in both the web-based (0.72-0.97) and the live exercises (0.68-0.89). Intraobserver and interobserver reliability of the total GLODS was shown to be excellent (0.92) and good (0.69), respectively. CONCLUSIONS:Ultrasound is a reliable tool for evaluating bone erosions, cartilage change, and joint malalignment in the hand joints of patients with RA. These features can be reliably integrated into a global ultrasound score.

Musculoskeletal ultrasound (MSUS) is a well-established and reliable tool for the evaluation of entheses and enthesitis, particularly at larger and accessible sites. Recent technological advances, including high- and ultra-high-frequency transducers, have expanded its potential, enabling detailed assessment of distal extremity entheses. This narrative review provides a focused and updated perspective on this evolving field, highlighting three key advances. First, the identification and characterization of previously underrecognized entheseal sites in the distal extremities, such as pulley systems, retinacula, novel tendon insertions, and collateral ligaments, broadening the morphological spectrum of entheseal imaging. This is complemented by improved evaluation of vascularization through microvascular imaging and contrast-enhanced US (CEUS). Second, the emergence of interventional approaches, particularly US-guided entheseal biopsy, offers a novel means to investigate entheseal tissue in vivo and may establish a link between imaging and histopathology. Third, the integration of advanced functional imaging modalities, including elastography and multispectral optoacoustic tomography (MSOT), provides preliminary additional insights into the biomechanical and molecular properties of the enthesis beyond conventional structural assessment. Collectively, these developments support new investigational perspectives, positioning MSUS as a dynamic and integrative modality capable of exploring new anatomical territories and biological dimensions, with the potential to reshape the understanding and evaluation of entheseal involvement in rheumatology.

Interstitial lung disease (ILD) is one of the most important extra-articular manifestations of rheumatoid arthritis (RA) due to its associated significant mortality. The availability of pharmacological treatments capable of slowing its progression, especially when initiated early, makes early diagnosis an essential part of its management. The low sensitivity of chest X-ray or lung function tests to identify RA-ILD in the early stages of the disease, together with the cost, accessibility, and ionizing radiation limitations of high-resolution computed tomography (HRCT), especially when serial screening or follow-up studies are required, has prompted the study of lung ultrasound (LUS) as an additional aid for the screening, diagnosis, and/or follow-up of RA-ILD. Based on the safety, low cost, and accessibility of LUS, and the encouraging results of research into this technique in ILD associated with systemic sclerosis, progress has been made in its validation process with research addressing aspects such as its accuracy, feasibility, and reliability. Negative predictive value and sensitivity values exceeding 80–90% have been reported, suggesting its potential utility. Feasibility has been suggested since LUS scan can be performed in less than 10 minutes, and intra- and inter-observer or examiner reliability shows values in the good to excellent range. However, there are still aspects that require further investigation, such as the standardization of the LUS scanning protocol or the requirements to ensure an effective learning curve before applying the technique in clinical practice. It is necessary to recognize the inherent limitations of LUS and understand that it should be considered a tool to aid in the early identification of patients who require HRCT, which is currently the diagnostic gold standard.

Objectives To provide a comprehensive description of a standardised, landmark-based ultrasound (US) technique for evaluating the lateral costotransverse (LCTL), supraspinous (SSL) and iliolumbar (ILL) ligaments of the thoracolumbar spine and to assess its reliability, feasibility and its potential applicability in spondyloarthritis (SpA).Methods LCTL, SSL and ILL were examined using US in specimens, followed by dissection to confirm structure location and validate US findings using a standardised anatomic-based and sonoanatomic-based landmark approach. The US technique was subsequently applied in 20 healthy controls (HC), in whom feasibility and inter-rater and intra-rater reliability among four operators with different expertise were assessed. Ligament visualisation was scored as: 0, not visualised; 1, incompletely visualised; 2, perfectly visualised. The technique was tested in three patients with SpA to evaluate its applicability.Results Anatomical study confirmed location and landmarks for all three ligaments. 120 ligaments were assessed in two rounds in HC. Visualisation scores ranged from 1 to 2 in 100% LCTL, 99.1% SSL and 85.9% ILL, with score 2 obtained in 69.6% of 960 assessments. Mean examination time decreased from 12′17″ to 10′56″ between rounds, with no significant differences between operators. Intra-rater and inter-rater agreement ranged from moderate to high. In patients with SpA, US detected both inflammatory and structural lesions in the three ligament entheses.Conclusion The proposed standardised US approach allows reliable assessment of LCTL, SSL and ILL. This technique provides a robust and reproducible method for evaluating the ligaments of the thoracolumbar spine and opens a new approach to the US assessment of patients with spinal inflammatory diseases, including SpA.

Ultrasound in medicine has a history arbitrarily going back to the days when a modified custom-built metal flaw detector was used in post-War Glasgow to diagnose abdominal masses. Spanning a period of 30 years, the article describes the coming of age of ultrasound within the field of rheumatology. This historical paper highlights collaborative research focusing on validation and standardization of the imaging modality. In addition, the work of several persons who have played a key role in the development of ultrasound in the field of rheumatology is emphasized. In real time and at the point of care, ultrasound can demonstrate where inflammation is present, thereby giving doctors and patients a better idea of why and where pain and stiffness originate. In retrospect, we may conclude that ultrasound has profoundly changed the practice of clinical rheumatology.

Objective Conventional radiography (CR) and ultrasound (US) are used interchangeably for identification of calcium pyrophosphate deposition (CPPD). The aim of this study was to assess whether combining US and CR offers greater accuracy over either modality alone for the identification of CPPD. Methods Consecutive patients scheduled for knee replacement surgery for osteoarthritis were enrolled. Before surgery, patients underwent CR and US of the knee. Menisci and hyaline cartilage were collected and analyzed using polarized light microscopy to confirm the presence of CPPD (gold standard). CR and US were assessed for absence/presence of CPPD by expert radiologists and sonographers. Diagnostic performance statistics were calculated. Poisson models with robust variance estimators were used to determine the likelihood of identifying CPPD. Results Fifty-one patients (63% female, mean age 71.4 [SD 8] years) were enrolled. US demonstrated higher overall accuracy than CR for CPPD identification (0.78 vs 0.73). Sequential use of both modalities provided an advantage when only 1 knee site was positive in 1 of the 2 techniques; however, when 2 or 3 sites were positive, no additional advantage was observed. When US was negative, subsequent CR did not improve CPPD detection, but in cases of a negative CR, a positive US increased the likelihood of CPPD by 4.21 times, whereas a negative US substantially reduced the probability of CPPD, increasing the likelihood of its absence by 76%. Conclusion US was more accurate than CR for identification of CPPD. Performing both exams can be an added value for CPPD identification only in a few specific cases.

Background/Objectives: The objective of this study is to investigate the intra- and inter-explorer reliability of different lung ultrasound (LUS) scores in patients with suspected rheumatoid arthritis with associated interstitial lung disease (RA-ILD). Methods: Fourteen consecutive patients with suspected RA-ILD based on the presence of respiratory symptoms, lung function tests (LFTs) or imaging alterations were recruited. The screening protocol consisted of an LFT, a chest X-ray, and HRCT. LUS examinations of different B-line and pleural line scores including 14 intercostal spaces were performed by three experienced sonographers, guaranteeing blinding. Intra- and inter-explorer reliability were calculated for all LUS scores and at the intercostal space level by weighted Cohen’s kappa and Fleiss’ kappa, respectively, relying on absolute differences using Stata/IC 14.2 software® (StataCorp, College Station, TX, USA). Results: Both global (ĸ = 0.73–0.82) and binary (ĸ = 0.80–0.90) scores of B lines showed substantial to excellent intra-explorer reliability, with slightly better results for the binary score. The inter-explorer reliability was equally excellent for the global score (ĸ = 0.93) and the binary score (ĸ = 0.90) of B lines. The intra-explorer reliability of the semiquantitative pleural score was excellent for all the sonographers (ĸ = 0.88–0.91), and the binary pleural score had slightly lower intra-explorer reliability (ĸ = 0.77–0.84). Regarding inter-explorer reliability, both semiquantitative and binary pleural scores were equally excellent (ĸ = 0.84). Good to excellent inter-explorer reliability was found in all the scanned areas. Conclusions: Substantial to excellent intra- and inter-explorer reliability of different feasible B-line and pleural LUS scores were found, adding evidence in favor of the potential implementation of LUS for RA-ILD diagnosis in clinical practice.

Osteoarthritis (OA) is a prevalent condition with significant clinical and epidemiological consequences, requiring a multidisciplinary approach. One potential solution is the establishment of specialized, comprehensive healthcare centers to address OA effectively. A previous initiative focused on the development of Centers of Excellence (CoEs) for rheumatoid arthritis (RA), and endorsed by the Pan American League of Associations for Rheumatology (PANLAR), aimed to establish CoEs for select rheumatic conditions, providing a framework for their accreditation.

La osteoartritis (OA) es una condición prevalente con importantes consecuencias clínicas y epidemiológicas, que requiere un abordaje multidisciplinario. Una posible solución es el establecimiento de centros de atención médica integrales y especializados para abordar la OA de manera eficaz. Una iniciativa previa, centrada en el desarrollo de Centros de Excelencia (CoE) para la artritis reumatoide (AR), y avalada por la Liga Panamericana de Asociaciones de Reumatología (PANLAR), tuvo como objetivo establecer CoE para ciertas afecciones reumáticas, proporcionando un marco para su acreditación.

Objectives To develop an EULAR training model for education in synovial tissue biopsy (STB) under ultrasound guidance (UG) following a stepwise approach: (1) development of educational material on UGSTB in large and small joints; (2) assessment of the validity, reliability and feasibility of the UGSTB educational procedure on cadaveric specimens; (3) validation of this procedure in live patients.Methods Using a nominal group (NG) and a DELPHI consensus methodology, educational audio-visual (AV) material and minimal requirements for education in UGSTB were developed by an expert panel. Then the experts performed an UGSTB on cadaveric joints using the developed approach. The samples retrieved from the cadaveric joints were confirmed histologically and the procedure was then tested by a group of ultrasonographers with different expertise for feasibility and face validity. The AV material and the practical procedures’ phases were subsequently ranked by the experts to finalise the training model for performing UGSTB in patients. The ST retrieved in patients was assessed for tissue quality.Results Based on NG and DELPHI processes, educational material and a stepwise standardised cadaver-based training model were developed. The knee was the cadaveric joint with the highest yield of histologically good quality of ST. 90% of the UGSTB from patients showed synovial membrane and 77% intact lining layer.Conclusions This EULAR endeavour provided a consensus-based comprehensive educational material and a practical cadaver-based model for training in UGSTB, which has shown feasibility and validity in tissue acquisition in specimens and patients.

We read with great interest the article titled "A Proposal for a New Lung Ultrasound Score in Rheumatoid Arthritis: The Reliability of Lung Ultrasound for Rheumatoid Arthritis-Associated Interstitial Lung Disease Diagnosis" [...].

OBJECTIVE:To develop and validate a minimally invasive ultrasound (US)-guided biopsy technique to collect entheseal tissue from the common extensor tendon (CET) enthesis at the lateral humeral epicondyle. METHODS:Seven sonographers performed a US examination of the CET on six human cadaveric upper limbs to locate the enthesis using an anatomical landmark-based approach. An adapted mini-arthroscopic system was introduced under US guidance to the target site for sample collection. At the end of the procedure, a dye was injected through the guide needle, followed by dissection, to confirm the sampling location. Histology and immunohistochemistry analyses were performed to assess the quality and representativeness of the samples. The reliability of the procedure among operators was evaluated by analysing the rate of successful sampling. RESULTS:24 samples were collected. The target site to be biopsied was identified as the insertion of the extensor carpi radialis brevis component of the CET. On dissection, the stain used to verify sampling accuracy was confirmed within the defined target area, with no damage to adjacent structures. Histology and immunohistochemistry indicated that most of the samples exhibited characteristics consistent with entheseal tissue (21 out of 24). All participants identified the CET and successfully completed the procedure, demonstrating reliable sample quality across operators. CONCLUSION:We developed a landmark-based approach to perform a minimally invasive full controlled US-guided biopsy of the CET enthesis that showed to be feasible and reproducible. We believe that this standardised, minimally invasive technique will widespread a reliable collection of entheseal tissue for future clinical and translational studies.

Background: Arterial variations in the upper limb, although infrequent, carry critical clinical implications. The presence of superficial ulnar and radial arteries, especially when originating from high levels, increases the risk of iatrogenic injury, misdiagnosis, and surgical complications. To confirm and describe, through ultrasound and anatomical dissection, the presence of a high-origin superficial ulnar artery and a superficial radial artery in a cadaver, highlighting their anatomical trajectory and clinical relevance. Methods: A cross-sectional ultrasound and anatomical study was conducted on 150 upper limbs from fresh-frozen cadavers. High-frequency ultrasound was used to scan the vasculature from the axilla to the wrist. Subsequently, dissection was performed to confirm sonographic findings. Results: One case (0.66%) of concurrent superficial ulnar artery and superficial radial artery was identified in the left arm of a 79-year-old male cadaver. The superficial ulnar artery originated from the axillary artery and coursed superficially along the forearm, anterior to the flexor muscles. The superficial radial artery emerged from the brachial artery and ran subcutaneously in the distal forearm. These arteries remained in close relation to key neural and venous structures, increasing their vulnerability to clinical error. Conclusions: The identification of high-origin superficial arteries is essential for clinical practice. Ultrasound serves as a reliable, non-invasive method for detecting such variations preoperatively. Awareness of these anomalies can prevent inadvertent vascular injuries, improve diagnostic accuracy, and inform safer surgical and anesthetic approaches in upper limb interventions.