Correlation between Severity of Synovitis and Clinical Features in Rotator Cuff Tears.

BACKGROUND: Rotator cuff tears can be asymptomatic in some cases; however, even when the tear size is small, clinical symptoms can be very severe. This suggests that symptoms of rotator cuff tears are related to factors other than the size. Although synovitis has been cited as one of the factors, there is no grading system for synovitis in rotator cuff tears. Moreover, there are few studies that evaluated the relationship between synovitis and clinical features in patients with rotator cuff tears. METHODS: Patients with medium-sized rotator cuff tears, who were scheduled for arthroscopic repair, were recruited for this study. The glenohumeral joint was divided into 4 quarters. Then, vascularity and hypertrophy of the joint were graded in each quarter using a modified scoring system. Clinical assessment was performed preoperatively and at 3 months and 6 months after surgery. Finally, correlation between the severity of synovitis and clinical features was analyzed. RESULTS: The intraobserver correlation coefficient was 0.815 to 0.918 and the interobserver correlation coefficient was 0.779 to 0.992 for the single measurement. Vascularity was significantly correlated with the range of motion, strength, and constant score within 6 months after surgery. Hypertrophy was correlated with the range of motion within 6 months after surgery. CONCLUSIONS: Synovitis in the shoulder with rotator cuff tears can be graded by using our modified scoring system. The severity of synovitis was closely related to the clinical features after surgery. Therefore, when treating patients with rotator cuff tears, treatment of synovitis should also be considered.

A convolutional neural network with transfer learning for automatic discrimination between low and high-grade synovitis: a pilot study.

Ultrasound-guided synovial tissue biopsy (USSB) may allow personalizing the treatment for patients with inflammatory arthritis. To this end, the quantification of tissue inflammation in synovial specimens can be crucial to adopt proper therapeutic strategies. This study aimed at investigating whether computer vision may be of aid in discriminating the grade of synovitis in patients undergoing USSB. We used a database of 150 photomicrographs of synovium from patients who underwent USSB. For each hematoxylin and eosin (H&E)-stained slide, Krenn's score was calculated. After proper data pre-processing and fine-tuning, transfer learning on a ResNet34 convolutional neural network (CNN) was employed to discriminate between low and high-grade synovitis (Krenn's score < 5 or ≥ 5). We computed test phase metrics, accuracy, precision (true positive/actual results), and recall (true positive/predicted results). The Grad-Cam algorithm was used to highlight the regions in the image used by the model for prediction. We analyzed photomicrographs of specimens from 12 patients with arthritis. The training dataset included n.90 images (n.42 with high-grade synovitis). Validation and test datasets included n.30 (n.14 high-grade synovitis) and n.30 items (n.16 with high-grade synovitis). An accuracy of 100% (precision = 1, recall = 1) was scored in the test phase. Cellularity in the synovial lining and sublining layers was the salient determinant of CNN prediction. This study provides a proof of concept that computer vision with transfer learning is suitable for scoring synovitis. Integrating CNN-based approach into real-life patient management may improve the workflow between rheumatologists and pathologists.

La sinoviortesis radioisotópica en el control de la sinovitis refractaria en Castilla La-Mancha. Una experiencia de 10 años / Radioisotope synoviorthesis in the control of refractory synovitis in Castilla-La Mancha. A 10-year experience

Nuestro hospital es el hospital de referencia en medicina nuclear para la realización de la sinoviortesis radioisotópica para toda Castilla La-Mancha. OBJETIVO: Describir la experiencia en la realización de la sinoviortesis radioisotópica en las artritis refractarias a otros tratamientos en nuestro hospital. METODOLOGÍA: Estudio observacional, descriptivo y transversal protocolizado a través de la revisión de la base de datos de las sinoviortesis radioisotópicas realizadas entre 2007 y 2017. Se recopilaron datos clínicos previos (edad, sexo, proceso patológico, tratamientos previos, infiltración previa y articulación afectada) y evolutivos a los 6 meses tras administrar el isótopo. Se creó una base de datos Excel para un análisis de frecuencias con SPSS 21. RESULTADOS: Se realizaron 30 radiosinoviortesis, siendo las enfermedades más frecuentes, por este orden: sinovitis villonodular pigmentada (40%), artritis reumatoide (23,3%), espondiloartritis (13,3%), osteoartritis (10%) y artritis inespecíficas (6,7%), seguido de lupus eritematoso sistémico y gota. Tras 6 meses un 56,7% de los pacientes mejoraron frente a un 36,7% que seguían igual. Así mismo, ninguno de ellos presentó complicaciones relacionadas con el procedimiento. A un 6,6% de los pacientes se les perdió el seguimiento. DISCUSIÓN Y CONCLUSIONES: En los pacientes con episodios de artritis de repetición con derrame articular asociado en una o 2 articulaciones, refractarias a tratamientos sistémicos, a las infiltraciones locales con corticoides y en aquellos pacientes en los que otros tratamientos puedan estar contraindicados, debemos considerar la posibilidad de realizar una radiosinoviortesis isotópica, pues es una técnica sencilla, segura y con una tasa de éxito superior al 50%

Our hospital is the nuclear medicine referral hospital for radioisotopic synoviorthesis for all of Castilla-La Mancha. OBJECTIVE: To describe the experience in the performance of radioisotopic synoviorthesis for arthritis refractory to other treatments in our hospital. METHODOLOGY: Observational, descriptive and cross-sectional study protocolised through the review of the database of radioisotopic synoviorthesis performed between 2007 and 2017. Previous clinical data were collected (age, sex, pathology, previous treatments, previous infiltration and affected joint), and progress at 6 months after administering the isotope. An Excel database was created for a frequency analysis with SPSS 21. RESULTS: 30 radiosynovitis interventions were performed. The most frequent pathologies in this order were: pigmented villonodular synovitis (40%), rheumatoid arthritis (23.3%), spondyloarthritis (13.3%), osteoarthritis (10%) and nonspecific arthritis (6.7%), followed by systemic lupus erythematosus and gout. After 6 months, 56.7% of the patients improved compared to 36.7% who remained the same. Likewise, none of them presented complications related to the procedure. Six point six percent of the patients were lost to follow-up. DISCUSSION AND CONCLUSIONS: In patients with episodes of recurrent arthritis with associated joint effusion in one or two joints, refractory to systemic treatments, to local infiltrations with corticosteroids and for patients for whom other treatments may be contraindicated, we must consider the possibility of performing an isotope radiosinoviortesis, as it is a simple, safe technique with a success rate of more than 50%

Ultrasound is not associated with the presence of systemic autoimmunity or symptoms in individuals at risk for rheumatoid arthritis.

Objective: To identify whether musculoskeletal ultrasound (MSUS) abnormalities are associated with specific phases of rheumatoid arthritis (RA) development in individuals at risk of RA. Methods: This is a prospective cohort study of individuals at risk of developing RA, namely first-degree relatives of patients with RA (RA-FDRs) without evidence of established rheumatic disease at inclusion. The inflammatory activity on MSUS was assessed according to a validated score (SONAR). Active MSUS was defined as a total B-mode score greater than 8, including at least one joint with significant synovitis (grade 2 or 3) or significant synovial hyperaemia (Doppler score greater than 1). We used logistic regression to analyse associations between MSUS findings and recognised preclinical phases of RA development, adjusting for other demographic and biological characteristics. Results: A total of 273 RA-FDRs were analysed, of whom 23 (8%) were anticitrullinated protein autoantibodies-positive, 58 (21%) had unclassified arthritis and 96 (35%) had an active MSUS, which was only associated with unclassified arthritis (OR: 1.8, 95% CI 1.0 to 3.3). Conclusion: In individuals at risk of RA, active MSUS was associated with the presence of unclassified arthritis, but not with any of the earlier described phases of RA development. These findings do not support an indiscriminate use of ultrasound in a screening strategy for preclinical RA.

Classifying glenohumeral synovitis: a novel intraoperative scoring system.

BACKGROUND: Synovitis of the shoulder is a common entity that is poorly described. This study aims to create a simple and reliable classification system for glenohumeral synovitis, which would benefit further research related to synovitis and outcomes. METHODS: Twenty 30-second shoulder arthroscopy videos were distributed to 19 fellowship-trained orthopedic surgeons. The observers responded with their years in practice, fellowship type, whether synovitis affects outcomes, and whether synovitis affects plans. The surgeons then rated the videos based on the following: color of capsule (pale, pink, or red); villous projections (none, few, or extensive); capillaries in capsule (scattered or hypertrophied); and axillary recess (normal or contracted). Scores ranging from 0 to 6 were assigned. The videos were randomized and redistributed at a later date. Statistical analysis used an intraclass correlation coefficient with a mixed-effects model to calculate variability based on observer. RESULTS: Nineteen observers completing the survey twice resulted in 760 videos being scored. There were 12 shoulder surgeons and 7 sports surgeons. Only 4 surgeons believed that synovitis did not affect outcomes, and the remaining 15 believed that it did. The intraclass correlation coefficient showed that 68% of the variation in measured scores was due to variation among patients and only 4% was due to variation among observers. There was no significant variation seen in scores due to surgeon experience, surgeon specialty, or first and second viewing. CONCLUSIONS: This interclass observer reliability shoulder synovitis study defined a system with excellent reliability among a range of surgeons with diverse training and experience. In addition, there was excellent reliability for the same surgeon between viewings.

Preliminary Definitions for the Sonographic Features of Synovitis in Children.

OBJECTIVE: Musculoskeletal ultrasonography (US) has the potential to be an important tool in the assessment of disease activity in childhood arthritides. To assess pathology, clear definitions for synovitis need to be developed first. The aim of this study was to develop and validate these definitions through an international consensus process. METHODS: The decision on which US techniques to use and the components to be included in the definitions, as well as the final wording, were developed by 31 US experts in a consensus process. A Likert scale of 1-5 (where 1 = complete disagreement and 5 = complete agreement) was used. A minimum of 80% of the experts scoring 4 or 5 was required for final approval. The definitions were then validated on 120 standardized US images of the wrist, metacarpophalangeal joints, and tibiotalar joints, displaying various degrees of synovitis at various ages. RESULTS: B-mode and Doppler should be used for assessing synovitis in children. A US definition of the various components (i.e., synovial hypertrophy, effusion, and Doppler signal within the synovium) was developed. The definition was validated on still images with a median of 89% of participants (range 80-100) scoring it as 4 or 5 on a Likert scale. CONCLUSION: US definitions of synovitis and its elementary components covering the entire pediatric age range were successfully developed through a Delphi process and validated in a web-based still-images exercise. These results provide the basis for the standardized US assessment of synovitis in clinical practice and research.

Does the Age of a Patient Affect the Outcome of Temporomandibular Joint Arthroscopic Surgery?

PURPOSE: Although temporomandibular joint (TMJ) disorders encompass all age groups, it is generally considered to affect young to middle-age adults. The aim of this investigation was to study patients who met the criteria for TMJ arthroscopy and to determine whether there was a difference in outcomes between younger and older patients. MATERIALS AND METHODS: This was a retrospective chart review of patients who underwent TMJ operative arthroscopy. The primary variable studied was patient age. Major outcome variables included changes in subjective pain measured by a visual analog scale (VAS) and changes in maximum interincisal opening (MIO) after arthroscopic surgery. Other variables of interest included the presence of systemic disease, synovitis, and osteoarthritis diagnosed arthroscopically. Data analysis included the Student t test, regression analysis (R Studio, Boston, MA), and χ2 test with a P value less than .05 indicating statistical significance. RESULTS: The study population consisted of 103 patients diagnosed with internal derangement and severe inflammatory or degenerative TMJ disease (Wilkes stages II to V) who underwent operative arthroscopy. Patients were divided into 2 groups based on age (group Y, <40 yr old, n = 51, mean age, 26 yr; group O, >40 yr old, n = 52, mean age, 56 yr). The presence of osteoarthritis diagnosed arthroscopically was significantly greater in group O than in group Y (P < .01). There was significant postoperative improvement in pain (VAS) and MIO in group Y (P < .01) and group O (P < .01). Although the 2 groups showed substantial improvement after arthroscopy, when comparing differences in outcomes between the groups, the absolute postoperative pain level for group O was significantly lower than for group Y (P < .05). Comparison of postoperative MIO did not show a significant difference between group Y and group O (P = .286). CONCLUSIONS: Groups Y and O showed substantial improvement in pain (VAS) and mandibular mobility (MIO) after surgical TMJ arthroscopy. Group O had a higher prevalence of arthroscopically diagnosed osteoarthritis and lower postoperative pain levels compared with group Y. Older patients with advanced TMJ disease responded well to TMJ arthroscopy.

[Ultrasound examination in rheumatoid arthritis]. / Gelenk-Ultraschall bei rheumatoider Arthritis.

Musculoskeletal ultrasound in the clinical routine praxis increases the hit rate for the diagnosis of inflammatory joint diseases. Power Doppler ultrasound is helpful in the detection of subclinical synovitis in the small finger joints in patients with rheumatoid arthritis; subclinical synovitis can lead to severe joint destruction. Rigorous clinical remission criteria result in lower synovitis detected by power Doppler ultrasound.

Grading of ultrasound Doppler signals in synovitis: does it need an update?

OBJECTIVES: To compare subjective estimation with computerized quantification of synovial perfusion in active RA, develop new quantitative scores, establish quantitative limit values for the respective grades in order to achieve even distribution and compare the new scores with the established semi-quantitative score. METHODS: Patients fulfilling the 2010 RA classification criteria in whom US showed power Doppler signals in one or more wrist or MCP joints were included. Right and left wrists and MCP joints 1-5 were examined with dorsal and volar scans. The proportion of the synovium covered by Doppler signals was estimated and quantified electronically in the area with the greatest fraction of colour signals. RESULTS: Forty-one RA patients [29 females, mean age 62 years (s.d. 14), disease duration 11 years (s.d. 13), 28-joint DAS 5.5 (s.d. 1.3)] were examined. Colour signals were found in 192 of 984 joint regions. Forty-two, 139 and 11 regions were allocated to the semi-quantitative grades 1, 2 and 3, respectively, with electronically calculated colour fractions of 3.9%, 12.6% and 29.7%. The mean estimated colour fractions were lower than the mean measured fractions. An even distribution of the scores was found for estimated colour fractions of >0-10% for grade 1, >10-25% for grade 2 and >25% for grade 3 and for measured colour fractions of >0-6% for grade 1, >6-12% for grade 2 and >12% for grade 3. CONCLUSION: This study suggests replacing the semi-quantitative grading system for synovial Doppler US with more evenly distributed quantitative scores that might better reflect treatment response.

Validation of the 2010-ACR/EULAR -classification criteria using newly EULAR-defined erosion for rheumatoid arthritis on the very early arthritis community-based (VErA) cohort.

OBJECTIVE: To validate the 2010-ACR/EULAR criteria for rheumatoid arthritis (RA), taking into account the recent EULAR definition of "erosive disease", on the 310 patients comprising the very early arthritis cohort (VErA). METHODS: 2010-criteria performances were tested by first strictly applying its three items successively: ≥ 1 clinical synovitis/another disease(s)/score ≥ 6/10), then the typical erosion grid without obtaining a score of ≥ 6 to diagnose RA. We tested successively: no erosion (S1), ≥ 1 erosion(s) (S2), EULAR-defined erosive disease (S3). Two gold standards were used: expert diagnosis at six years and EULAR erosive disease at two years. RESULTS: At inclusion, median age was 52 years; median RA duration 4.2 months. 2010-ACR/EULAR criteria, including EULAR-defined erosive disease applied at baseline, classified comparable numbers of patients as the 1987 criteria (P=0.27). Using expert diagnosis at six years, more patients were classified as RA with S2 than 1987-ACR criteria (P<0.04). In contrast, sensitivity and specificity indicated that 2010-ACR/EULAR-S3 criteria performed slightly but not significantly better than 1987-ACR criteria. On ROC curves, a score ≥ 6 correctly classified RA. When EULAR-defined erosion at two years was the gold standard, the 1987-ACR, the 2010-S1, -S2 and -S3 criteria performed comparably. CONCLUSIONS: Using the very early community-based, conservatively treated VErA cohort, the strict application of 2010-ACR/EULAR criteria using the new EULAR definition of erosive disease or not performed slightly but not significantly better than the 1987-ACR criteria.

Diagnosis and classification of rheumatoid arthritis.

Rheumatoid arthritis (RA) is a systemic chronic inflammatory disease of unclear etiology that is manifested in by a progressive and destructive polyarthritis in association with serological evidence of autoreactivity. Its diagnosis is based on the classification criteria that involve four parameters: joint involvement, serology (rheumatoid factor and anti-cyclic citrullinated peptide--anti-CCP), levels of acute phase reactants and the duration of the symptoms Aletaha, et al. [1]. This classification simplifies the categorization of the patients with early RA; however, the diagnosis requires highly trained specialists who are able to differentiate early symptoms of RA from other pathologies.

Three groups in the 28 joints for rheumatoid arthritis synovitis--analysis using more than 17,000 assessments in the KURAMA database.

Rheumatoid arthritis (RA) is a joint-destructive autoimmune disease. Three composite indices evaluating the same 28 joints are commonly used for the evaluation of RA activity. However, the relationship between, and the frequency of, the joint involvements are still not fully understood. Here, we obtained and analyzed 17,311 assessments for 28 joints in 1,314 patients with RA from 2005 to 2011 from electronic clinical chart templates stored in the KURAMA (Kyoto University Rheumatoid Arthritis Management Alliance) database. Affected rates for swelling and tenderness were assessed for each of the 28 joints and compared between two different sets of RA patients. Correlations of joint symptoms were analyzed for swellings and tenderness using kappa coefficient and eigen vectors by principal component analysis. As a result, we found that joint affected rates greatly varied from joint to joint both for tenderness and swelling for the two sets. Right wrist joint is the most affected joint of the 28 joints. Tenderness and swellings are well correlated in the same joints except for the shoulder joints. Patients with RA tended to demonstrate right-dominant joint involvement and joint destruction. We also found that RA synovitis could be classified into three categories of joints in the correlation analyses: large joints with wrist joints, PIP joints, and MCP joints. Clustering analysis based on distribution of synovitis revealed that patients with RA could be classified into six subgroups. We confirmed the symmetric joint involvement in RA. Our results suggested that RA synovitis can be classified into subgroups and that several different mechanisms may underlie the pathophysiology in RA synovitis.

The Canadian Early Arthritis Cohort (CATCH): patients with new-onset synovitis meeting the 2010 ACR/EULAR classification criteria but not the 1987 ACR classification criteria present with less severe disease activity.

OBJECTIVE: Our objective was to describe characteristics of Canadian patients with early arthritis and examine differences between those fulfilling 1987 and 2010 rheumatoid arthritis (RA) classification criteria. METHODS: The Canadian Early Arthritis Cohort (CATCH) is a national, multicenter, observational, prospective cohort of patients with early inflammatory arthritis, receiving usual care, recruited since 2007. Inclusion criteria include age > 16 years; symptom duration 6-52 weeks; swelling of ≥ 2 joints or ≥ 1 metacarpophalangeal/proximal interphalangeal joint; and 1 of rheumatoid factor ≥ 20 IU, positive anticitrullinated protein antibodies (ACPA), morning stiffness ≥ 45 min, response to nonsteroidal antiinflammatory drug, or positive metatarsophalangeal joint squeeze test. Data from patients enrolled to March 15, 2011, were analyzed. RESULTS: In total, 1450 patients met the eligibility criteria (1187 were followed). At baseline, mean age was 53 ± 15 years, symptom duration was 6.1 ± 3.2 months, Disease Activity Score (DAS28) was 4.9 ± 1.6, Health Assessment Questionnaire-Disability Index was 1.0 ± 0.7. Forty-one percent (n = 450) of patients had moderate (3.2 < DAS28 ≤ 5.1) and 46% (n = 505) had high (DAS28 > 5.1) disease activity; 28% of those with baseline radiographs (n = 250/908) had radiographic evidence of erosions. ACPA status was available for 70% (n = 831) of patients; 55% (n = 453) tested positive. Sixty percent (n = 718) of patients were treated with methotrexate (MTX) initially. Of 612 patients without erosions, 63% and 83% fulfilled 1987 and 2010 RA classification criteria, respectively. Seventy-three percent (n = 166) of those who did not fulfill 1987 criteria were newly identified by the 2010 criteria. These patients had less severe disease and more were MTX-naive compared to those satisfying the 1987 criteria. Forty-seven percent of all patients achieved remission at 1 year. CONCLUSION: Patients with early RA present with moderate high disease activity; < 50% achieve remission at 1 year, despite MTX treatment in the majority. The 2010 RA classification criteria identify more patients with RA who would previously have been designated as having undifferentiated disease. However, these patients have lower disease activity at the time of identification.

Profiling the clinical presentation of diagnostic characteristics of a sample of symptomatic TMD patients.

BACKGROUND: Temporomandibular disorder (TMD) patients might present a number of concurrent clinical diagnoses that may be clustered according to their similarity. Profiling patients' clinical presentations can be useful for better understanding the behavior of TMD and for providing appropriate treatment planning. The aim of this study was to simultaneously classify symptomatic patients diagnosed with a variety of subtypes of TMD into homogenous groups based on their clinical presentation and occurrence of comorbidities. METHODS: Clinical records of 357 consecutive TMD patients seeking treatment in a private specialized clinic were included in the study sample. Patients presenting multiple subtypes of TMD diagnosed simultaneously were categorized according to the AAOP criteria. Descriptive statistics and two-step cluster analysis were used to characterize the clinical presentation of these patients based on the primary and secondary clinical diagnoses. RESULTS: The most common diagnoses were localized masticatory muscle pain (n = 125) and disc displacement without reduction (n = 104). Comorbidity was identified in 288 patients. The automatic selection of an optimal number of clusters included 100% of cases, generating an initial 6-cluster solution and a final 4-cluster solution. The interpretation of within-group ranking of the importance of variables in the clustering solutions resulted in the following characterization of clusters: chronic facial pain (n = 36), acute muscle pain (n = 125), acute articular pain (n = 75) and chronic articular impairment (n = 121). CONCLUSION: Subgroups of acute and chronic TMD patients seeking treatment can be identified using clustering methods to provide a better understanding of the clinical presentation of TMD when multiple diagnosis are present. Classifying patients into identifiable symptomatic profiles would help clinicians to estimate how common a disorder is within a population of TMD patients and understand the probability of certain pattern of clinical complaints.

[US evaluation of the hands and feet in rheumatoid arthritis]. / Comment je fais un bilan échographique des mains et des pieds dans la polyarthrite rhumatoïde?

Rheumatoid arthritis (RA) is a chronic inflammatory disease characterized by progressive damage of synovial-lined joints and variable extra-articular manifestations. Synovitis is usually found in the wrist, metacarpophalangeal, proximal interphalangeal and metatarsophalangeal joints. For these reasons, we believe that ultrasound with power doppler can be used for the detection and monitoring of synovitis with a simplified "hands and feet" protocol. In this article, we will describe this protocol used daily in our institution for early diagnosis and therapeutic management of this disease.

[Cross-sectional imaging of peripheral involvement in psoriatic arthritis]. / Nouvelle imagerie des atteintes périphériques du rhumatisme psoriasique.

The purpose of this article is to: 1) describe the main plain film, ultrasound and MR imaging features of peripheral involvement in psoriatic arthritis, 2) describe the advantages of ultrasound and MRI at the early stages of the disease; 3) describe how to use MRI and ultrasound in order to assess response to tumor necrosis factor-alpha blocker therapy.

[Cross-sectional imaging of peripheral involvement in ankylosing spondylitis]. / Imagerie moderne des atteintes périphériques dans la spondylarthrite ankylosante.

Ankylosing spondylitis is the most common spondyloarthropathy. It is characterized by enthesopathy (inflammation at the insertion of ligaments, tendons or fascia to bone). The os calcis is most frequently involved. Additional peripheral manifestations include synovitis and dactylitis. Unlike radiographs that demonstrate late manifestations of the disease, ultrasound and MRI demonstrate early inflammatory changes of bones and soft tissues. Multiple sites of involvement may also be detected on a single examination. Both imaging modalities facilitate early diagnosis, a crucial element for patient management. Both modalities may also monitor lesion regression during treatment.

Comparison of clinical versus ultrasound-determined synovitis in juvenile idiopathic arthritis.

OBJECTIVE: To compare clinical evaluation and ultrasonography (US) in the assessment of joint synovitis in children with juvenile idiopathic arthritis (JIA). METHODS: Thirty-two patients underwent clinical evaluation of 52 joints by 2 pediatric rheumatologists. Joints were assessed for swelling, tenderness/pain on motion, and restricted motion. The same joints were scanned independently by an experienced sonographer for synovial hyperplasia, joint effusion, and power Doppler (PD) signal. RESULTS: In total, 1,664 joints were assessed both clinically and with US. On clinical examination, 98 joints (5.9%) were swollen, 59 joints (3.5%) were tender, and 40 joints (2.4%) had restricted motion. On US evaluation, 125 joints (7.5%) had synovial hyperplasia, 153 joints (9.2%) had joint effusion, and 53 joints (3.2%) had PD signal. A total of 104 (6.3%) and 167 (10%) joints had clinical and US synovitis, respectively. Of the 1,560 clinically normal joints, 86 (5.5%) had subclinical synovitis (i.e., had synovitis on US). US led to classifying 5 patients as having polyarthritis who were classified as having oligoarthritis or were found to have no synovitis on clinical evaluation. US variables were moderately correlated with clinical measures of joint swelling, but poorly correlated with those of joint tenderness/pain on motion and restricted motion. Overall, correlations were lower for PD signal than for synovial hyperplasia and joint effusion. CONCLUSION: We found that subclinical synovitis as detected by US is common in children with JIA. This finding may have important implications for patient classification and may affect the choice of the optimal therapeutic strategy in individual patients.