A clinical perspective on imaging in juvenile idiopathic arthritis

In recent years, imaging has become increasingly important to confirm diagnosis, monitor disease activity, and predict disease course and outcome in children with juvenile idiopathic arthritis (JIA). Over the past few decades, great efforts have been made to improve the quality of diagnostic imaging and to reach a consensus on which methods and scoring systems to use. However, there are still some critical issues, and the diagnosis, course, and management of JIA are closely related to clinical assessment. This review discusses the main indications for conventional radiography (XR), musculoskeletal ultrasound (US), and magnetic resonance imaging (MRI), while trying to maintain a clinical perspective. The diagnostic-therapeutic timing at which one or the other method should be used, depending on the disease/patient phenotype, will be assessed, considering the main advantages and disadvantages of each imaging modality according to the currently available literature. Some brief clinical case scenarios on the most frequently and severely involved joints in JIA are also presented.

Validity of ultrasonography in detecting enthesitis in children: A systematic literature review

OBJECTIVE

A systematic review to assess the value of ultrasonography (US) for detecting enthesitis in juvenile idiopathic arthritis (JIA).

METHODS

PubMed and Embase databases were searched for articles published from January 1966 to May 2021; we selected those meeting the inclusion criteria according to the US definition of enthesitis and metric properties studied. We assessed the clinical features of the population, study design, the type and number of entheses examined, the definition and scoring system of US enthesitis and metric properties according to the OMERACT filter (truth, discrimination and feasibility). The quality of the studies was evaluated with the Quality Assessment of Diagnostic Accuracy Studies 2.

RESULTS

Five publications met the inclusion criteria (26 to 146 patients and 1 to 10 bilaterally examined entheses). All studies focused on lower-limb entheses. The elementary lesions included in the definition of adult enthesitis were generally assessed. Few studies reported US reliability and none evaluated sensitivity to change of US. US revealed entheseal abnormalities in 9.4 to 53% of JIA patients and 20 to 83% of enthesitis-related arthritis cases. No significant abnormalities were found in healthy children. US findings were poorly correlated with clinical examination. The overall quality of the studies was low, mainly because of the lack of a reference standard.

CONCLUSION

US is a sensitive tool to detect entheseal abnormalities in JIA. The current evidence highlights that a standardized US definition of enthesitis in children is lacking and US criteria and discriminant validity have not been established.

Associations between power Doppler ultrasound findings and B-mode synovitis and clinical arthritis in juvenile idiopathic arthritis using a standardised scanning approach and scoring system

OBJECTIVES

To describe power Doppler (PD) ultrasound findings in joint regions with B-mode (BM) synovitis using a standardised scanning protocol and scoring system in patients with juvenile idiopathic arthritis (JIA). Further, to examine associations between PD findings and BM synovitis, clinical arthritis, patient characteristics and disease activity.

METHODS

In this cross-sectional study, one experienced ultrasonographer, blinded to clinical findings, performed ultrasound examinations in 27 JIA patients with suspected clinical arthritis. The elbow, wrist, metacarpophalangeal 2-3, proximal interphalangeal 2-3, knee, ankle and metatarsophalangeal 2-3 joints were assessed bilaterally and scored semiquantitatively (grades 0-3) for BM and PD findings using a joint-specific scoring system with reference atlas. Multilevel mixed-effects ordered regression models were used to explore associations between PD findings and BM synovitis, clinical arthritis, age, sex, JIA subgroups, disease duration and 10-joint Juvenile Arthritis Disease Activity Score (JADAS10).

RESULTS

Twenty-one girls and six boys, median age (IQR) 8 years (6-12 years) were included. Overall, 971 joint regions were evaluated by ultrasound, 129 had BM synovitis and were assessed for PD. PD findings were detected in 45 joint regions (34.9%), most frequently in the parapatellar recess of the knee (24.4%). Increasing PD grades were associated with higher BM grades (OR=5.0,p<0.001) and with clinical arthritis (OR=7.4,p<0.001) but not with age, sex, JIA subgroups, disease duration or JADAS10.

CONCLUSION

Increasing severity of PD findings were significantly associated with BM synovitis and with clinical arthritis. This suggests that PD signals detected using a standardised ultrasound examination and scoring system can reflect active disease in JIA patients.

Contribution of Ultrasound in Current Practice for Managing Juvenile Idiopathic Arthritis

The interest and application of musculoskeletal ultrasound (MSUS) in juvenile idiopathic arthritis (JIA) are increasing. Numerous studies have shown that MSUS is more sensitive than clinical examination for detecting subclinical synovitis. MSUS is a well-accepted tool, easily accessible and non-irradiating. Therefore, it is a useful technique throughout JIA management. In the diagnostic work-up, MSUS allows for better characterizing the inflammatory involvement. It helps to define the disease extension, improving the classification of patients into JIA subtypes. Moreover, it is an essential tool for guiding intra-articular and peritendinous procedures. Finally, during the follow-up, in detecting subclinical disease activity, MSUS can be helpful in therapeutic decision-making. Because of several peculiarities related to the growing skeleton, the MSUS standards defined for adults do not apply to children. During the last decade, many teams have made large efforts to define normal and pathological US features in children in different age groups, which should be considered during the US examination. This review describes the specificities of MSUS in children, its applications in clinical practice, and its integration into the new JIA treat-to-target therapeutic approach.

Ultrasound Imaging-Based Methods for Assessing Biological Maturity during Adolescence and Possible Application in Youth Sport: A Scoping Review

Bone maturity is an indicator for estimating the biological maturity of an individual. During adolescence, individuals show heterogeneous growth rates, and thus, differences in biological maturity should be considered in talent identification and development. Radiography of the left hand and wrist is considered the gold standard of biological maturity estimation. The use of ultrasound imaging (US) may be advantageous; however, its validity and reliability are under discussion. The aims of this scoping review are (1) to summarize the different methods for estimating biological maturity by US imaging in adolescents, (2) to obtain an overview of the level of validity and reliability of the methods, and (3) to point out the practicability and usefulness of ultrasound imaging in the field of youth sports. The search included articles published up to November 2022. The inclusion criteria stipulated that participants had to fall within the age range of 8 to 23 years and be free of bone disease and fractures in the region of interest. Nine body regions were investigated, while the hand and wrist were most commonly analyzed. US assessment methods were usually based on the estimation of a bone maturity stage, rather than a decimal bone age. Furthermore, 70% of the assessments were evaluated as applicable, 10% expressed restraint about implementation, and 20% were evaluated as not applicable. When tested, inter- and intra-rater reliability was high to excellent. Despite the absence of ionization, low costs, fast assessment, and accessibility, none of the US assessments could be referred to as a gold standard. If further development succeeds, its application has the potential to incorporate biological age into selection processes. This would allow for more equal opportunities in talent selection and thus make talent development fairer and more efficient.

Role of Ultrasound Evaluation of Temporomandibular Joint in Juvenile Idiopathic Arthritis: A Systematic Review

Background: Juvenile idiopathic arthritis (JIA) is childhood’s most frequent chronic rheumatic disease. JIA is a broad term that includes all arthritides starting before 16 years, lasting at least six weeks, and of unknown cause. The temporomandibular joint (TMJ) could be involved in JIA both at onset and during the disease course. The presence of TMJ synovitis might severely impair dentofacial maturation in pediatric patients. The ultrasound (US) application to detect early signs of TMJ synovitis in children with JIA has provided contradictory results. We sought to assess the current role of TMJ US in JIA through a systematic literature review. Methods: The systematic review was conducted according to the recommendations of the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA). Results: The literature search found 345 records. After duplicates removal, 253 records were screened, 20 full-text articles were reviewed to assess their eligibility, and 7 of them were included in the qualitative analysis. Joint effusion was the most recorded parameter, followed by bony condylar abnormalities. Compared to contrast enhancement MRI, the capability to detect signs of active synovitis of TMJ by US is low, especially at the early stages. Conclusion: Understanding how US may help diagnose and manage children with JIA is advisable for several reasons. MRI cannot be frequently repeated, may need sedation, and is expensive. The constant technical improvement of US will undoubtedly allow for better evaluation of what, in the past, was not clear or not even captured by sonography. So far, the role of US in the assessment of TMJ involvement in JIA is indubitably secondary to the MRI. Even so, we think that a baseline MRI of TMJ and the repetition of the sonography over time might both help the interpretation of US images and intercept significative changes.

Procedures for the content, conduct and format of EULAR/PReS paediatric musculoskeletal ultrasound courses

Background

Despite the worldwide increasing request of education on paediatric musculoskeletal ultrasound (PedMSUS), content, conduct and format of PedMSUS courses have never been internationally agreed.

Objectives

To produce educational procedures for the conduct, content and format of EULAR/PReS PedMSUS courses.

Methods

After a systemic literature review and expert opinion collection, a panel of items for the development of procedures on PedMSUS courses was identified. Agreement on the items was assessed through Delphi surveys among a taskforce of 24 members, which included 18 experts in PedMSUS (8 rheumatologists, 1 radiologist, 9 paediatric rheumatologists), 1 methodologist and rheumatologist expert in MSUS, 2 patient research partners, 1 health professional in rheumatology and 2 EMEUNET/EMERGE members, from 8 different European countries. Each item was assessed through a 5-point Likert scale (0, full disagreement; 5, full agreement); agreement was reached for >75% of answers rating 4–5. All items with agreement were included in the preliminary core set of educational procedures, which underwent external assessment by a broader Consensus group (Faculty and Tutors of previous EULAR PedMSUS courses and PReS Imaging Working Party members), through Delphi survey.

Results

Two Delphi surveys produced the preliminary core set of procedures for basic, intermediate, advanced and teach-the-teachers (TTT) PedMSUS courses. A Delphi survey within the Consensus group produced agreement on the proposed procedures.

Conclusions

Shared EULAR/PReS procedures for the conduct, content and format of basic, intermediate, advanced and TTT PedMSUS courses were identified on international basis.

Doppler and Spectral Ultrasound of Sacroiliac Joints in Pediatric Patients with Suspected Juvenile Spondyloarthritis

Background: Power Doppler ultrasound (PDUS) with spectral wave analysis (SWA) has been compared with magnetic resonance imaging (MRI) in documenting active sacroiliitis in early spondyloarthritis (SpA) but, to date, PDUS/SWA has not been yet applied to the study of sacroiliac joints (SIJs) in children. Methods: A group of 20 children (13 F/7 M, mean age 14.2 y) with suspected juvenile SpA (jSpA) underwent PDUS/SWA and, subsequently, MRI of the SIJs. SIJs PDUS scoring and resistance index (RI) of the SIJs flows were recorded. The accuracy of PDUS/SWA for the diagnosis of active sacroiliitis was evaluated, with MRI as the gold standard. Results: PDUS signals were detected in 19 patients and 30 SIJs. Bone marrow edema (BME) lesions on MRI were detected in 12 patients (diagnosed as jSpA) and 22 SIJs. PDUS scoring on SIJs were higher in patients with a final diagnosis of jSpA (p = 0.003). On SWA, the mean RIs in patients with or without final diagnosis of active sacroiliitis were, respectively, 0.604 and 0.767 (p = 0.005) at joint level. A RI < 0.55 and PDUS > 1 showed the higher specificity for sacroiliitis (AUROC curve 0.854 for PDUS and 0.920 for RI). SIJs PDUS/SWA showed an overall concordance of 82.35%, with substantial agreement (k = 0.627) with MRI on the diagnosis of sacroiliitis. Conclusions: In children with sacroiliitis, PDUS demonstrates a rich vascularization into SIJs and low RIs (<0.55) have high specificity for this condition. SIJs PDUS/SWA could be useful as a screening method in children with suspected jSpA.

Discordance between Clinical and Ultrasound Examinations in Juvenile Idiopathic Arthritis: An Experimental Approach

Clinical examination (CE) and musculoskeletal ultrasound (MSUS) of ten joints (knee, ankle, wrist, elbow, II-MCP) and their extra-articular (EA) compartments (tendons and bursae) were performed on 35 consecutive patients with active juvenile idiopathic arthritis (JIA) (active group) to test how the extension of MSUS examinations to EA changes the concordance between MSUS and CE. The overall concordance between CE and MSUS, measured with Cohen’s Kappa (k), was moderate (k = 0.43); the addition of EA MSUS increased the concordance in all joints, with the exclusion of II-MCP (k = 0.49). In the ankle and wrist, the k increase was relevant (k from 0.13 to 0.27 and 0.11 to 0.41). In the active group patients, we observed 44 subclinical synovitis; the number of subclinical synovitis per patient was correlated with JADAS-27 (p = 0.03) and was higher in a control group composed of 15 patients with persistent disease remission (1.3 vs. 0.4 p = 0.03). Our results show that EA compartments should always be evaluated during MSUS. Furthermore, we demonstrate a moderate concordance between CE and MSUS in JIA; the finding of subclinical synovitis is common in patients with active diseases and is related to disease activity.

Ultraschalldiagnostik in der Kinderrheumatologie

Der Artikel gibt einen Überblick zum aktuellen Stand der Ultraschallbefundung in der Kinderrheumatologie und geht insbesondere auf den praktischen Einsatz und die technischen Aspekte der Gelenksonografie ein. Dabei werden auch die wissenschaftlichen Entwicklungen der letzten Jahre zusammengefasst und berücksichtigt. Neben der Gelenksonografie wird die Ultraschalltechnik in der Kinderrheumatologie zunehmend auch auf weitere Körperregionen und -organe ausgeweitet, die für die kinderrheumatologische Diagnostik relevant sind.

Ultrasonography in Pediatric Rheumatology

This review highlights the increasing evidence from the last few years supporting the use of musculoskeletal ultrasonography (MSUS) in the evaluation and management of patients with pediatric rheumatic diseases, particularly focusing on juvenile idiopathic arthritis. Recently developed definitions for the sonographic appearance of healthy and pathologic joints in children are discussed. Further topics explored include how MSUS enhances the diagnosis of inflammatory joint disease (synovitis, enthesitis, tenosynovitis), including the detection of subclinical synovitis. There is a brief summary on the use of ultrasonography in the evaluations of myositis, Sjögren syndrome, and scleroderma.

Upper-Limb Entheses in Healthy Children: A Comprehensive Ultrasound Study

BACKGROUND

Interest in ultrasound (US) as a diagnostic tool in spondyloarthritis is growing. Although the literature has provided detailed description of normal lower-limb entheses for adults and children, validated normal US findings of the pediatric upper-limb (UL) entheses are lacking.

OBJECTIVES

The aim of this study was to describe the sonographic characteristics of the UL entheses in healthy children to provide a basis for assessing pathologic findings in children with rheumatic diseases.

METHODS

This is an observational, cross-sectional study. The recruited healthy children were grouped according to age: group 1, 3-9 years (n = 22); group 2, 10 to 13 years (n = 12); and group 3, 14 to 18 years (n = 9). The following UL entheses were examined: (1) supraspinatus, (2) common flexor, (3) common extensor, and (4) triceps. Ultrasound examination was performed in B mode for morphology and structural abnormalities, and power Doppler was applied to detect vascularization within the enthesis and cartilage sites.

RESULTS

Forty-three children with a median age of 9 years (6-13 years) were included; 55% were boys. A total of 344 entheses were evaluated; all of them presented a homogeneous hyperechoic fibrillar pattern. Tendon insertion thickness at the bone attachment site increased with age and was greater in males. No signs of chronic enthesopathy were detected. Doppler signal was observed in children from groups 1 and 2, but not in any of the patients in group 3. In group 1, intraentheses signal was detected in the common extensor tendon insertion as an isolated signal (n = 2 patients), whereas intracartilage signal was detected in the supraspinatus (n = 1 patient) and the triceps (n = 1 patient). In group 2, intracartilage signal was detected in the common extensor (n = 2 patients) and the common flexor (n = 2 patients). Interobserver agreement for the entheses' thickness was as follows: intracorrelation coefficient class (ICC) of 0.86 (95% confidence interval [CI], 0.84-0.92) for the supraspinatus enthesis, ICC of 0.83 (95% CI, 0.83-0.90) for the common extensor enthesis, ICC of 0.96 (95% CI, 0.91-0.97) for the common flexor enthesis, and ICC of 0.94 (95% CI, 0.89-0.95) for the triceps enthesis. The κ index was 0.93 for the detection of the power Doppler signal. Intraobserver agreement was good for all evaluated entheses: ICC of 0.85 (95% CI, 0.83-0.91) for supraspinatus, ICC of 0.86 (95% CI, 0.84-0.91) for common extensor entheses, ICC of 0.89 (95% CI, 0.86-0.93) for common flexor entheses, and ICC of 0.96 (95% CI, 0.90-0.97) for evaluation of triceps entheses. The κ index was 0.91 for the detection of Doppler signal.

CONCLUSIONS

The current study provides a comprehensive description of the structural appearance and vascularization of UL entheses on healthy children. This information can be useful as reference for interpretation of pathological findings in children with musculoskeletal diseases in clinical practice.

Development and reliability of a novel ultrasonographic joint-specific scoring system for synovitis with reference atlas for patients with juvenile idiopathic arthritis

Objective

To develop an ultrasonographic image acquisition protocol and a joint-specific scoring system for synovitis with reference atlas in patients with juvenile idiopathic arthritis (JIA) and to assess the reliability of the system.

Methods

Seven rheumatologists with extensive ultrasound experience developed a scanning protocol and a semiquantitative joint-specific scoring system for B-mode (BM) synovitis for the elbow, wrist, metacarpophalangeal 2–3, proximal interphalangeal 2–3, hip, knee, ankle and metatarsophalangeal 2–3 joints. An ultrasonographic reference atlas for BM synovitis, divided in four age groups (2–4, 5–8, 9–12, 13–18 years), and power Doppler (PD) activity was then developed. Reliability was assessed for all joints on still images and in a live exercise including 10 patients with JIA, calculated by intraclass correlation coefficient (ICC) and weighted kappa.

Results

A scanning protocol and scoring system for multiple joints with reference atlas composed of images with four different score levels for BM and PD were developed. Still image scoring for BM synovitis on joint level showed good to excellent intra-reader reliability (ICC/kappa ranges: 0.75–0.95/0.63–0.91) and moderate to excellent inter-reader reliability (ICC/kappa ranges: 0.89–0.99/0.50–0.91). Still image scoring for PD activity showed excellent intra-reader and inter-reader reliability (ICC/kappa: 0.96/0.91 and ICC/kappa: 0.97/0.80, respectively). In the live scoring, inter-reader reliability (ICC/kappa) was moderate to excellent for BM synovitis (0.94/0.51) and PD activity (0.91/0.60).

Conclusion

An ultrasonographic image acquisition protocol and joint-specific scoring system with reference atlas were developed and demonstrated moderate to excellent reliability for scoring of synovitis in patients with JIA. This can be a valuable tool in clinical practice and future research.

Application of the OMERACT synovitis ultrasound scoring system in juvenile idiopathic arthritis: a multicenter reliability exercise

OBJECTIVES

To evaluate the reliability of the OMERACT paediatric ultrasound (US) synovitis definitions and scoring system in JIA.

METHODS

Thirteen sonographers analysed 75 images for the presence/absence of elementary lesions (binary scoring) and for grading synovitis, synovial hypertrophy, effusion and Doppler signals. Static US images of the second metacarpophalangeal joint (MCP-II), wrist, elbow, knee and ankle in JIA patients at different ages and different disease stages were collected with standardized scanning by two experienced sonographers. Intra- and inter-reader reliability were analysed with kappa coefficients.

RESULTS

Intra-reader reliability was good for binary scoring (Cohen's kappa 0.62, range 0.47-0.75), synovitis and synovial hypertrophy; excellent for Doppler signals (quadratic weighted kappa 0.77, 0.66-0.86; 0.76, 0.61-0.84; and 0.87, 0.77-0.94, respectively); and moderate for effusion (0.55, 0.24-0.76). Inter-reader reliability was good for synovitis and synovial hypertrophy (Light's kappa 0.68, 95% CI: 0.61, 0.75 and 0.63, 0.54-0.71, respectively), excellent for Doppler signals (0.85, 95% CI: 0.77, 0.90), and moderate for binary scoring and effusion (0.48, 95% CI: 0.36, 0.64 and 0.49, 0.40-0.60, respectively). We obtained the best scores for the knee (0.71, 0.54-0.85) except for Doppler signals, with reliability higher for MCP-II. We found a trend toward better results in older children.

CONCLUSIONS

This is the first study establishing the reliability of the OMERACT paediatric US synovitis definitions and scoring system in the five most commonly affected joints in JIA. The reliability was good among a large group of sonographers. These results support the applicability of these definitions and scoring system in clinical practice and multicentre studies.

The new role of musculoskeletal ultrasound in the treat-to-target management of juvenile idiopathic arthritis

This article reviews the role of musculoskeletal ultrasound (MSUS) for the diagnosis, monitoring and treat-to-target management of JIA. Technological advancements in MSUS allow more precise evaluation of arthritis, tenosynovitis and enthesitis versus clinical examination alone, which may assist treatment decisions. In adult studies, serum and synovial biomarkers have correlated with MSUS findings. Within paediatric rheumatology, significant developments in the definition of normal and pathology, a necessity for the future integration of MSUS into treat-to-target management, have already been reached or are underway, which in turn could allow tighter control of disease activity and earlier identification of treatment response and failure, bringing the goal of 'precision medicine' closer. Additionally, the utility of MSUS for the evaluation of subclinical disease remains an unexamined area of interest. 'Ultrasound remission' combined with clinical assessment and immunological markers could therefore potentially improve the treat-to-target management of JIA.

Ultrasound imaging in paediatric rheumatology

The role of ultrasound imaging in the diagnosis and monitoring of paediatric rheumatic diseases with special emphasis on recent scientific work regarding the evidence base and standardization of this technique is being reviewed. An overview of the most important practical aspects for the use of musculoskeletal ultrasound in a clinical setting is also provided. Huge scientific efforts and advances in recent years illustrate the increasing importance of musculoskeletal ultrasound in pediatric rheumatology. Several studies focused on setting an evidence-based standard for the ultrasound appearance of healthy and normal joints in children of all age groups. Physiologic vascularization and ossification were two main aspects of these studies. Other publications demonstrate that ultrasound imaging is also an important and useful tool to detect pathology as synovitis, tenosynovitis or enthesitis in children and to monitor pediatric patients with rheumatic conditions. Important practical aspects include training in the use of correct ultrasound techniques, as well as knowledge and experience of normal pediatric sonoanatomy and the appearance of pathological findings on ultrasound.

Emergence of Musculoskeletal Ultrasound Use in Pediatric Rheumatology

PURPOSE OF REVIEW

To summarize recent international efforts on standardization and validation of pediatric musculoskeletal ultrasound and determine its role in diagnosis and monitoring of disease in pediatric rheumatology.

RECENT FINDINGS

Over the past decade, significant progress has been made on building the evidence base for musculoskeletal ultrasound in pediatric rheumatology. This includes the clear definition of the sonographic appearance of the normal pediatric joint and enthesis on ultrasonography, definitions for pathology, and the establishment of a specific scoring system for the pediatric knee. Ultrasonography has been shown to have an important role in the detection of subclinical synovitis and can predict flares in children considered to be in remission clinically. Musculoskeletal ultrasound is likely going to play an important role in complementing the clinical exam especially in juvenile idiopathic arthritis. Given the powerful therapeutic tools available, it will support early diagnosis and precisely determine remission status. In a treat to target approach, it will greatly help to define the targets that need to be reached.

Current status and recent advances on the use of ultrasonography in pediatric rheumatic diseases

BACKGROUND

Ultrasonography has become a useful tool in the clinical rheumatology settings in the last two decades, but its use has only recently been explored by pediatric rheumatologists. The aim of this article is to review the literature on the current status and recent advances on the use of ultrasound in pediatric rheumatic diseases.

DATA SOURCES

We have retrieved and reviewed the relevant articles from MEDLINE/PubMed databases published so far, on the applications of ultrasound in juvenile idiopathic arthritis (JIA), systemic lupus erythematosus, dermatomyositis, enthesitis, Sjogren's syndrome, and other rheumatic diseases. In addition, articles on novel ultrasound imaging technology of potential use in pediatric rheumatology are also reviewed.

RESULTS

In JIA, ultrasound can be used to detect subclinical synovitis, to improve the classification of patients in JIA subtypes, to capture early articular damage, to monitor treatment response, and to guide intraarticular injections. Ultrasound is also considered useful in other rheumatic disorders for the evaluation of musculoskeletal symptoms, assessment of parotid gland pathology, and measurement of skin thickness and pathology. Novel ultrasound techniques developed to augment the functionality of ultrasonography may also be applicable in pediatric rheumatic disorders.

CONCLUSIONS

Ultrasound shows great promise in the assessment and management of children with rheumatologic disorders. However, standardization and validation of ultrasound in healthy children and in patients with rheumatic diseases are still needed.

OMERACT Definitions for Ultrasonographic Pathologies and Elementary Lesions of Rheumatic Disorders 15 Years On

OBJECTIVE

The Outcome Measures in Rheumatology (OMERACT) Ultrasound (US) Working Group (WG) operates research activities for the validation of US as an outcome measurement instrument according to the Filter 2.0 framework.

METHODS

Original publications on definitions and scoring systems for pathophysiological manifestations and elementary lesions of various rheumatic disorders were reviewed from the onset of the WG research in 2005.

RESULTS

Definitions and scoring systems according to new terminology are provided.

CONCLUSION

We have redefined OMERACT US pathology and elementary lesions as well as scoring systems, which are now proposed for OMERACT approval for application in clinical trials.

Merging into the mainstream: the evolution of the role of point-of-care musculoskeletal ultrasound in hemophilia

Bleeding with resultant hemophilic arthropathy constitutes the largest cause of morbidity in patients with hemophilia. It results from repeated bleeding episodes in the joint and is characterized by synovial hypertrophy and cartilage and bony destruction. Hemophilic arthropathy assessment is a continually evolving process and is particularly challenging in children and young adults in whom joint disease may be missed or underestimated as obtaining serial "baseline" magnetic resonance imaging scans of multiple clinically asymptomatic or nearly asymptomatic joints may be unjustifiable and cost-ineffective. Musculoskeletal ultrasound-particularly, point-of-care musculoskeletal ultrasound-has emerged as a promising imaging modality for the early detection and management of hemophilic arthropathy, and for the evaluation of hemarthrosis and painful musculoskeletal episodes in patients with hemophilia. This review summarizes currently available data on the emerging role of this new imaging modality, its limitations, and gaps in knowledge. The review also raises unanswered questions, highlights the need for consolidated research efforts, and delineates future directions expected to advance this technology and optimize its use in this patient population.

Novel Ultrasound Image Acquisition Protocol and Scoring System for the Pediatric Knee

OBJECTIVE

The use of musculoskeletal ultrasound is increasing among pediatric rheumatologists. Reliable scoring systems are needed for the objective assessment of synovitis. The aims of this study were to create a standardized and reproducible image acquisition protocol for B-mode and Doppler ultrasound of the pediatric knee, and to develop a standardized scoring system and determine its reliability for pediatric knee synovitis.

METHODS

Six pediatric rheumatologists developed a set of standard views for knee assessment in children with juvenile arthritis. Subsequently, a comprehensive literature review, practical exercises, and a consensus process were performed. A scoring system for both B-mode and Doppler was then developed and assessed for reliability. Interreader reliability or agreement among a total of 16 raters was determined using 2-way single-score intraclass correlation coefficient (ICC) analysis.

RESULTS

Twenty-one views to assess knee arthritis were initially identified. Following completion of practical exercises and subsequent consensus processes, 3 views in both B-mode and Doppler were selected: suprapatellar longitudinal and medial/lateral parapatellar transverse views. Several rounds of scoring and modifications resulted in a final ICC of suprapatellar view B-mode 0.89 (95% confidence interval [95% CI] 0.86-0.92) and Doppler 0.55 (95% CI 0.41-0.69), medial parapatellar view B-mode 0.76 (95% CI 0.68-0.83) and Doppler 0.75 (95% CI 0.66-0.83), and lateral parapatellar view B-mode 0.82 (95% CI 0.75-0.88) and Doppler 0.76 (95% CI 0.66-0.84).

CONCLUSION

A novel B-mode and Doppler image acquisition and scoring system for assessing synovitis in the pediatric knee was successfully developed through practical exercises and a consensus process. Study results demonstrate overall good-to-excellent reliability.

The OMERACT Stepwise Approach to Select and Develop Imaging Outcome Measurement Instruments: The Musculoskeletal Ultrasound Example

Objective.

To describe the Outcome Measures in Rheumatology (OMERACT) stepwise approach to select and develop an imaging instrument with musculoskeletal ultrasound (US) as an example.

Methods.

The OMERACT US Working Group (WG) developed a 4-step process to select instruments based on imaging. Step 1 applies the OMERACT Framework Instrument Selection Algorithm (OFISA) to existing US outcome measurement instruments for a specific indication. This step requires a literature review focused on the truth, discrimination, and feasibility aspects of the instrument for the target pathology. When the evidence is completely unsatisfactory, Step 2 is a consensus process to define the US characteristics of the target pathology including one or more so-called “elementary lesions”. Step 3 applies the agreed definitions to the image, evaluates their reliability, develops a severity grading of the lesion(s) at a given anatomical site, and evaluates the effect of the acquisition technique on feasibility and lesion(s) detection. Step 4 applies and assesses the definition(s) and scoring system(s) in cross-sectional studies and multicenter trials. The imaging instrument is now ready to pass a final OFISA check.

Results.

With this process in place, the US WG now has 18 subgroups developing US instruments in 10 different diseases. Half of them have passed Step 3, and the groups for enthesitis (spondyloarthritis, psoriatic arthritis), synovitis, and tenosynovitis (rheumatoid arthritis) have finished Step 4.

Conclusion.

The US WG approach to select and develop outcome measurement instruments based on imaging has been repeatedly and successfully applied in US, but is generic for imaging and fits with OMERACT Filter 2.1.

Ultrasonography for the orthopaedic surgeon

The recent development of high-frequency ultrasonography transducers has provided better accuracy and improved the ability to image more superficial body structures. Ultrasonography is a widely available, inexpensive, comparative, and dynamic imaging technique that involves no radiation exposure and has no other adverse effects. Ultrasonography must always be combined with a medical history, physical examination, and radiographic assessment. What is ultrasound-assisted orthopaedic surgery? This approach consists in the use of ultrasonography by orthopaedic surgeons during patient visits and/or in the operating room. Similar to arthroscopy, ultrasonography is used as a complementary technique by physicians involved in the management of musculo-skeletal disease (e.g., radiologists, rheumatologists, and sports physicians). What knowledge of biophysics is needed to use ultrasonography? The surgeon must be familiar with the mechanisms by which the ultrasound waves are generated and received during B-mode and Doppler ultrasonography and with possible types of image artefacts. What is the procedure for examining a structure by ultrasonography? Each anatomic component must be assessed along two perpendicular planes in scanning mode. What does ultrasonography contribute during patient visits? Ultrasonography provides additional diagnostic information and helps to explain the pathological process to the patient. How does the contribution of ultrasonography vary across body sites and pathological processes? Ultrasonographic imaging is easier at some body sites than at others. Ultrasonography can provide useful information in patients with joint disease, sports injuries, osteo-articular infections, peripheral neuropathy, or tumours. What is interventional ultrasonography in orthopaedic surgery? Ultrasound-guided orthopaedic interventions include injections, aspirations, and minimally invasive surgical procedures. How can orthopaedic surgeons incorporate ultrasonography into their practice? The surgeon must purchase an ultrasound machine dedicated to the musculo-skeletal system and follow the necessary training courses.

Educational initiatives and training for paediatric rheumatology in Europe

The Paediatric Rheumatology European Society (PReS) has over many years, developed a portfolio of educational activities to address increasing educational needs of workforce and support young clinicians to acquire skills to develop new knowledge and deliver clinical care in the future. These educational activities aim to facilitate growth of paediatric rheumatology and ultimately improve the clinical care for children and families. This article describes the current portfolio of PReS educational activities and their relevance to the international paediatric rheumatology community.

The role of imaging in juvenile idiopathic arthritis

INTRODUCTION

The prognosis of juvenile idiopathic arthritis (JIA) has changed dramatically due to the availability of novel drugs. Prompt diagnosis and treatment are essential to prevent permanent joint damage. As a result, methods to improve JIA diagnosis and prognosis are of high priority to tailor treatment strategies and maximize their efficacy. Musculoskeletal ultrasound and magnetic resonance imaging are more sensitive than clinical examination and radiography in the detection of joint involvement and might play a substantial role to optimize the management of JIA. Areas covered: This review compiles an inventory of potential uses of imaging studies in the modern practice of pediatric rheumatology, together with a critical analysis of the major challenges that are still to be addressed. Imaging appearance of normal growth-related changes of the musculoskeletal system will be discussed. Expert commentary: Knowledge of the evolving patterns of skeletal maturity is paramount to define pathological findings and avoid misinterpretations. Establishing a novel radiological algorithm for a rational use of imaging in JIA is of high priority to allow a speedier integration of imaging into the clinical workflow and decision-making process.

Normative ultrasound references for the paediatric wrist; dorsal soft tissues

Objective

To report novel ultrasound (US) references for the healthy paediatric wrist.

Methods

Healthy children and adolescents had an US examination including Doppler, of the right wrist, using a mid-sagittal image through the radiocarpal (RC)/midcarpal (MC) joints. These features were noted: appearances and depth of the recess, with an additional measurement in the flexed position and number of Doppler signals within the recess in close proximity to the joint. In a second, blinded session, all images were reassessed by the same observer.

Results

In total, 116 subjects (59 girls) aged 6–16 years (mean 10 years and 11 months) were included. The RC recess was visible in 71, of which 60 were non-bulging and 11 were bulging. In flexion, the thickness decreased in 60 (84.5%), suggestive of joint fluid. Of the 54 visible MC recesses, 45 (83.3%) thinned in flexion. The mean depths of the RC and MC recesses were 0.4 mm (SD 0.5, range 0–2.9) and 0.5 mm (SD 0.6, range 0–2.4), respectively, with no differences according to sex, but with increasing depths by age.

For the RC joints, at least one Doppler signal was seen in the recess in 9/116 joints (7.8%), whereas this was true for 3.5% of the MC recesses. There were no statistically significant association between the depth of the RC or MC recesses and number of hand active sport activities (P=0.733 and P=0.091, respectively).

Conclusion

The appearances of the dorsal RC and MC recesses in healthy children may mimic pathology. Hence, findings should be interpreted carefully.