Enthesitis and Related Changes in the Knees in Seronegative Spondyloarthropathies and Skin Psoriasis: Magnetic Resonance Imaging Case-Control Study

Diagnosis of Inflammatory Bowel Disease-Associated Peripheral Arthritis: A Systematic Review

BACKGROUND

Inflammatory bowel disease (IBD)-associated peripheral spondyloarthritis (pSpA) decreases quality of life and remains poorly understood. Given the prevalence of this condition and its negative impact, it is surprising that evidence-based disease definitions and diagnostic strategies are lacking. This systematic review summarizes available data to facilitate development and validation of diagnostics, patient-reported outcomes, and imaging indices specific to this condition.

METHODS

A literature search was conducted. Consensus or classification criteria, case series, cross-sectional studies, cohort studies, and randomized controlled trials related to diagnosis were included.

RESULTS

A total of 44 studies reporting data on approximately 1500 patients with pSpA were eligible for analysis. Data quality across studies was only graded as fair to good. Due to large heterogeneity, meta-analysis was not possible. The majority of studies incorporated patient-reported outcomes and a physical examination. A total of 13 studies proposed or validated screening tools, consensus, classification, or consensus criteria. A total of 28 studies assessed the role of laboratory tests, none of which were considered sufficiently accurate for use in diagnosis. A total of 17 studies assessed the role of imaging, with the available literature insufficient to fully endorse any imaging modality as a robust diagnostic tool.

CONCLUSIONS

This review highlights existing inconsistency and lack of a clear diagnostic approach for IBD-associated pSpA. Given the absence of an evidence-based approach, a combination of existing criteria and physician assessment should be utilized. To address this issue comprehensively, our future efforts will be directed toward pursuit of a multidisciplinary approach aimed at standardizing evaluation and diagnosis of IBD-associated pSpA.

The value of different involvement patterns of the knee "synovio-entheseal complex" in the differential diagnosis of spondyloarthritis, rheumatoid arthritis, and osteoarthritis: an MRI-based study

OBJECTIVES

To explore the different involvement patterns of the knee "synovio-entheseal complex (SEC)" on MRI in patients with spondyloarthritis (SPA), rheumatoid arthritis (RA), and osteoarthritis (OA).

METHODS

This study retrospectively included 120 patients (male:female, 55:65) with a mean age of 39.20 years diagnosed with SPA (n = 40), RA (n = 40), and OA (n = 40) at the First Central Hospital of Tianjin between January 2020 and May 2022. Six knee entheses were assessed by two musculoskeletal radiologists according to the SEC definition. Bone marrow lesions associated with entheses include bone marrow edema (BME) and bone erosion (BE), which were classified as entheseal or peri-entheseal based on their relationship to the entheses. Three groups (OA, RA, and SPA) were established to characterize the location of enthesitis and the different SEC involvement patterns. Inter-group and intra-group differences were analyzed using the ANOVA or chi-square tests, and the inter-class correlation coefficient (ICC) test was used to determine inter-reader agreement.

RESULTS

The study contained a total of 720 entheses. The SEC-based analysis revealed different involvement patterns in three groups. The OA group had the most abnormal signals in tendons/ligaments (p = 0.002). The RA group had considerably greater synovitis (p = 0.002). The majority of peri-entheseal BE was identified in the OA and RA groups (p = 0.003). Furthermore, entheseal BME in the SPA group was significantly different from those in the other two groups (p < 0.001).

CONCLUSIONS

SEC involvement patterns differed in SPA, RA, and OA, which is important for differential diagnosis. SEC should be used as a whole evaluation method in clinical practice.

KEY POINTS

• The "synovio-entheseal complex (SEC)" explained differences and characteristic alterations in the knee joint in patients with spondyloarthritis (SPA), rheumatoid arthritis (RA), and osteoarthritis (OA). • The various SEC involvement patterns are crucial for differentiating SPA, RA, and OA. • When "knee pain" is the only symptom, a detailed identification of characteristic alterations in the knee joint of SPA patients may help timely treatment and delay the structural damage.

Translational Research Studies Unraveling the Origins of Psoriatic Arthritis: Moving Beyond Skin and Joints

Patients with psoriatic arthritis (PsA) are suffering from a decreased quality of life despite currently available treatments. In the latest years, novel therapies targeting the IL-17/IL-23 and TNF pathways improved clinical outcome. Despite this, remission of disease is not achieved in a considerable group of patients, continuous treatment is very often required to reach clinical remission, and prevention of PsA in patients with psoriasis (PsO) is currently impossible. A better understanding of PsA pathogenesis is required to develop novel treatment strategies that target inflammation and destruction more effectively and at an early stage of the disease, or even before clinically manifest disease. The skin is considered as one of the sites of onset of immune activation, triggering the inflammatory cascade in PsA. PsO develops into PsA in 30% of the PsO patients. Influenced by environmental and genetic factors, the inflammatory process in the skin, entheses, and/or gut may evolve into synovial tissue inflammation, characterized by influx of immune cells. The exact role of the innate and adaptive immune cells in disease pathogenesis is not completely known. The involvement of activated IL-17A+ T cells could implicate early immunomodulatory events generated in lymphoid organs thereby shaping the pathogenic inflammatory response leading to disease. In this perspective article, we provide the reader with an overview of the current literature regarding the immunological changes observed during the earliest stages of PsA. Moreover, we will postulate future areas of translational research aimed at increasing our knowledge on the molecular mechanisms driving disease development, which will aid the identification of novel potential therapeutic targets to limit the progression of PsA.

Physical Activity and Investigation With Magnetic Resonance Imaging Partly Explain Variability in the Prevalence of Patellar Tendon Abnormalities: A Systematic Review With Meta-analysis of Imaging Studies in Asymptomatic Individuals

OBJECTIVE

To estimate the pooled prevalence of, and factors associated with, the presence of patellar tendon abnormalities observed on imaging in people without symptoms.

DESIGN

Systematic review with stratified meta-analysis and meta-regression.

LITERATURE SEARCH

We searched Embase, Scopus, MEDLINE, CINAHL, SPORTDiscus, and Web of Science from 1980 to August 2020.

STUDY SELECTION CRITERIA

We included studies that reported the prevalence of asymptomatic patellar tendon abnormalities on imaging. We excluded studies of participants with current tendon pain, a history of tendon pain, or other systemic conditions.

DATA SYNTHESIS

Stratification and meta-regression of studies based on study-level descriptive statistics (mean age, body mass index, proportion of female participants, physical activity participation, imaging modality) were performed using a random-effects model to account for between-study heterogeneity. Risk of bias was assessed using the modified Newcastle-Ottawa scale.

RESULTS

Meta-analysis of 64 studies (7125 limbs from 4616 participants) found significant between-study heterogeneity (I²≥90%, P<.01), which precluded a summary prevalence estimate. Heterogeneity was partially explained by studies that included participants who were physically active and studies that assessed tendon abnormalities using magnetic resonance imaging compared to ultrasound (P<.05). Mean age, body mass index, proportion of female participants, and sample size did not explain the remaining heterogeneity.

CONCLUSION

There was substantial variability in the reported prevalence of asymptomatic patellar tendon abnormalities. A clear and valid method is needed to assess and report the presence of patellar tendon abnormalities to increase research capacity and establish the clinical value of imaging the patellar tendon. J Orthop Sports Phys Ther 2021;51(5):216-231. Epub 28 Mar 2021. doi:10.2519/jospt.2021.10054.

Recent Advances in Imaging for Diagnosis, Monitoring, and Prognosis of Psoriatic Arthritis

Psoriatic arthritis (PsA) is an inflammatory condition characterized by a strong heterogeneity and multifaceted behavior. PsA manifests in two types—axial and peripheral—which may be present at the same time. Peripheral manifestations can be further divided into the articular (arthritis) and extra-articular (i.e., enthesitis and dactylitis) subgroups. In such a complex disease, imaging is often required to characterize the type of involvement and to evaluate the radiological damage and progression of PsA. In addition, imaging plays a pivotal role in clinical practice; that is, for axial involvement. Conventional radiology has been the main standard of reference for many years. However, in recent years, there has been growing interest in different imaging modalities, such as ultrasonography (US) and magnetic resonance imaging (MRI). All these techniques play a role in the diagnosis and follow-up of patients with PsA and cover all the types of the disease. US and MRI have good sensitivities and specificities for detecting synovitis, and this may be helpful for differential diagnosis with other musculoskeletal diseases and useful in the early or preclinical phases of the disease. However, US is not useful in the diagnosis of axial PsA. In addition, other modalities have been investigated in the field of PsA imaging. Computed tomography (CT), in particular, dual energy-CT and high-resolution peripheral CT (HRpQ-CT) might play an important role in the assessment of bone damage, erosions, and new bone formation. Regarding advanced functional imaging, FDG PET/CT is another interesting technique for exploring disease activity.

Magnetic Resonance Imaging of Enthesitis in Spondyloarthritis, Including Psoriatic Arthritis-Status and Recent Advances

Enthesitis, inflammation at the attachment sites of tendons, ligaments, fascia, and joint capsules to bones plays a critical role in the pathogenesis of spondyloarthritis (SpA), including psoriatic arthritis (PsA). Magnetic resonance imaging (MRI) has aided in a better understanding of pathophysiology, early diagnosis, prognostication, therapeutic outcomes, and follow up of enthesitis. The concept of enthesitis as a focal insertional pathology has transformed over the past decade, with the help of MRI, to a more widespread entity involving both bone and surrounding soft tissues. The utility of MRI in the differential diagnosis of suspected enthesitis has recently been explored. With the emergence of the treat-to-target concept, and a domain-based approach in the management of SpA, objective and sensitive monitoring of response to targeted therapy becomes prudent. Properties like high sensitivity, ability to image intra-osseous pathology along with surrounding structures exemplify the utility of MRI technology. Considering the lack of a comprehensive, validated MRI score the Outcome Measures in Rheumatology (OMERACT) MRI in Arthritis Working Group, informed by a systematic literature review, developed the first international, consensus-based MRI-scoring system, combined with MRI definitions of pathologies for enthesitis in patients with spondyloarthritis (SpA) and PsA. An atlas with representative images of each grade of the scoring system was subsequently developed by the group to aid readers interested in using the heel enthesitis MRI scoring system (HEMRIS). The HEMRIS can find utility in clinical trials targeting enthesitis as the primary outcome. MRI also finds value for global assessment of the total burden of enthesitis. The concept of whole-body MRI (WBMRI), enabling visualization of entheses throughout the body using a single image is relatively new. The MRI whole-body score for inflammation in peripheral joints and entheses (MRI-WIPE) is a promising scoring system, which is undergoing further testing in clinical trials and longitudinal cohorts evaluating global measures of inflammation at entheses. This review discusses the role of MRI in diagnosis and monitoring of enthesitis in SpA and PsA, along with recent advances in the field, based on published literature.

Imaging in rheumatoid arthritis, psoriatic arthritis, axial spondyloarthritis, and osteoarthritis: An international viewpoint on the current knowledge and future research priorities

Imaging is increasingly used in the routine management of rheumatic diseases as well as in the clinical trials of these disorders. This viewpoint, authored by a group of international imaging experts following two meetings dedicated to imaging in rheumatology, reports a consensus about the current knowledge and addresses where further research should be focused based on the views of the international imaging experts and discussion of the evidence with attending imaging practitioners. The goal was to maximize the potential of imaging to improve the clinical management of four rheumatic diseases. These rheumatic diseases include rheumatoid arthritis, psoriatic arthritis, axial spondyloarthritis, and osteoarthritis.

Utility of Magnetic Resonance Imaging in Diagnosis and Monitoring Enthesitis in Patients with Spondyloarthritis: An OMERACT Systematic Literature Review

Objective.

A systematic literature review was performed to document published magnetic resonance imaging (MRI) lesion definitions and scoring systems for enthesitis in spondyloarthritis (SpA).

Methods.

PubMed, Embase, and Cochrane Library databases were searched for original publications involving adult patients with SpA undergoing MRI of axial/peripheral joints. Selected articles were assessed for quality using a standardized assessment tool and metric indices.

Results.

Considering the heterogeneous design, quality, and outcome measures of studies, statistical data pooling was considered inappropriate. A qualitative narrative of results was undertaken based on study designs.

Conclusion.

Lack of a comprehensive, validated score warrants additional research to develop an MRI enthesitis scoring system. PROSPERO registration number: CRD42018090537.

The Epidemiology of Psoriatic Arthritis

Psoriatic arthritis (PsA) is a chronic systemic inflammatory disorder characterized by joint and entheseal inflammation with a prevalence of 0.05% to 0.25% of the population and 6% to 41% of patients with psoriasis. PsA is a highly heterogeneous inflammatory arthritis. In this review, current knowledge is discussed regarding the epidemiology of PsA, including disease manifestations, classification criteria for adult and juvenile PsA, methods for recognizing early PsA, including use of screening tools and knowledge of risk factors for PsA, and medical comorbidities associated with PsA.

Evidence-based recommendations on the role of dermatologists in the diagnosis and management of psoriatic arthritis: systematic review and expert opinion

BACKGROUND

Psoriatic arthritis (PsA) can develop at any time during the course of psoriasis.

AIMS

The aims of these practical recommendations are to help dermatologists identify patients at risk of PsA, to diagnose PsA in collaboration with rheumatologists and to gain a better understanding of initial PsA management.

MATERIALS AND METHODS

A scientific committee consisting of 10 dermatologists and a rheumatologist selected clinically relevant questions to be addressed by evidence-based recommendations using the DELPHI method. For each question, a systematic literature review was performed in Medline, Embase and the Cochrane Library databases. The levels of evidence of all selected and reviewed articles were appraised according to the Oxford levels of evidence.

RESULTS

An expert board of 30 dermatologists reviewed and analysed the evidence and developed recommendations for the selected questions. Agreement among participants was assessed on a 10-point scale, and the potential impact of the recommendations on clinical practice was evaluated. Among the 6960 references identified, 190 relevant articles were included in the reviews. Three recommendations regarding risk factors for PsA and one regarding PsA prevalence were issued. The mean agreement score between participants varied from 7.8 to 9.6. Three recommendations on PsA screening tools that can be used by dermatologists were issued. The mean agreement score between participants varied from 7.7 to 9.4. Initial PsA treatment options according to published guidelines were critically appraised for axial and peripheral involvement and enthesitis/dactylitis. Three recommendations were issued. The mean agreement score between participants varied from 7.6 to 8.7.

DISCUSSION

The systematic literature research and meta-analyses did not provide high-quality evidence to support recommendations regarding PsA screening. Conversely, PsA treatment options were supported by strong evidence.

CONCLUSION

Cooperation between dermatologists and rheumatologists should be emphasized to better identify and manage PsA patients.

MR imaging assessment of arthritis of the knee

The magnetic resonance (MR) imaging presentations of arthritis of the knee are important for radiologists to recognize because these disorders are often clinically unsuspected. When they are known or clinically suspected, knowledge of imaging features allows for the confirmation and characterization of the extent of disease. This article reviews the fundamental MR imaging manifestations of rheumatologic disorders of the knee and their presentation in specific arthropathies.

Magnetic resonance imaging of the hand joints in patients with inflammatory bowel disease and arthralgia: a pilot study

OBJECTIVES

To assess whether subclinical inflammatory changes are present on magnetic resonance imaging (MRI) in patients with inflammatory bowel disease (IBD) and arthralgia.

METHOD

In this pilot study, painful hand joints [metacarpophalangeal (MCP), proximal interphalangeal (PIP), and/or distal interphalangeal (DIP)] of 11 IBD patients (age 18-45 years) with continuous pain for > 6 weeks were scanned on a 1.5-T extremity MRI system. A control group of 11 IBD patients without joint pain who were matched for type and disease duration of IBD, gender, and age was included. All patients were clinically examined by a rheumatologist for the presence of pain and arthritis. Imaging was performed according to a standard arthritis protocol with intravenous contrast administration on the same day. Images (blinded for clinical information) were evaluated by two readers in consensus for the presence of joint fluid, synovitis, tenosynovitis, enthesitis, erosions, cartilage defects, and bone marrow oedema.

RESULTS

Enthesitis was seen in three hand joints (MCP 2, MCP 3, PIP 3) of 2/11 (18%) arthralgia patients and in none of the control group (p = 0.48). A small amount of subchondral bone marrow oedema was seen in the metacarpal head of two controls. No other abnormalities were observed.

CONCLUSIONS

Several young IBD patients with chronic hand pain had subclinical inflammation on MRI, which invites for further study in a larger group of patients.

Imaging in psoriatic arthritis

Psoriatic arthritis (PsA), a chronic inflammatory arthritis associated with psoriasis, is often associated with significant inflammation and joint damage leading to a decrease in quality of life measures. Plain radiographs have traditionally been used to detect and estimate the extent of joint damage. Newer imaging modalities such as ultrasound and MRI however, have provided the ability to detect joint damage earlier and measure the extent of joint damage more accurately, than with radiographs. These imaging modalities also provide a sensitive means of assessing for the presence of and quantifying the amount of inflammation. Furthermore, these imaging modalities can help with the identification of enthesitis, tendonitis, and dactylitis, features that can help make a diagnosis of PsA. Additionally, MRI and scintigraphy can help in the early detection and assessment of sacroiliitis and axial disease. In addition to benefits with diagnosis and prognosis, recent advances in imaging techniques have led to their increased use in the assessment of efficacy of novel therapies for psoriatic arthritis. Imaging modalities therefore allow for early detection, assessment of joint inflammation and joint damage as well as in the estimation of disease activity of PsA and thereby enable the clinician to treat PsA early, adequately, and safely.

The critical role of interleukin-23 in spondyloarthropathy

The spondyloarthropathies represent highly enigmatic conditions and although their clinical features, anatomical distribution of disease and genetic predisposing factors have been known for some time, a unified concept of the basic pathobiology underlying these illnesses has remained undefined. Recently progress has been made because numerous independent studies have converged upon IL-23 as a central cytokine in spondyloarthropathy and the mechanism and sites of action of this cytokine have now become much clearer. These findings enable the rational design of therapeutic strategies which it is hoped will profoundly modify the progression of these diseases. We will review the anatomical sites affected and the evidence for the importance of IL-23 in these conditions, before drawing these lines of investigation together to propose a model for the unified understanding of spondyloarthropathy.

Effect of Enthesitis on 1505 Brazilian Patients with Spondyloarthritis

Objective.

To analyze the clinical effect of enthesitis in a large Brazilian cohort of patients with spondyloarthritis (SpA).

Methods.

A common protocol of investigation was prospectively applied to 1505 patients with SpA in 29 centers in Brazil. Clinical and demographic variables and disease indexes were investigated. The Maastricht Ankylosing Spondylitis Enthesitis Score was used to investigate the enthesitis component. Ankylosing spondylitis was the most frequent disease in the group (65.4%). Others were psoriatic arthritis (18.4%), undifferentiated SpA (6.7%), reactive arthritis (3.3%), and enteropathic arthritis (3.2%).

Results.

At least 1 affected enthesis was observed in 54% of the patients with SpA, with a mean of 2.12 ± 2.98 entheses affected. According to the clinical presentation, enthesitis was significantly more frequent in patients with axial + peripheral joint involvement compared to isolated axial or peripheral involvement (p < 0.001). There was a statistical association between the presence of enthesites and axial symptoms (buttock pain, cervical pain, and hip pain), and peripheral symptoms (lower limb arthritis, number of painful and swollen joints; p < 0.05). Patients with enthesitis also presented higher mean scores of Bath Ankylosing Spondylitis Functional Index (BASFI; p < 0.001), Bath Ankylosing Spondylitis Disease Activity Index (p < 0.001), and Ankylosing Spondylitis Quality of Life (ASQoL; p < 0.001). Multivariate logistic regression showed that BASFI (p < 0.0001; OR 74.839), ASQoL (p = 0.0001; OR 14.645), and Achilles tendonitis (p = 0.0059; OR 7.593) were associated with work incapacity.

Conclusion.

The clinical presence of enthesitis in this large cohort of patients with SpA was frequent and was associated with a significant increase in disease activity and decline in functional capacity and quality of life.

Arthritis mimicking sports-related injuries

Arthritis, including inflammatory, crystal deposition, and synovial proliferative disorders, may mimic sports injury. The purpose of this article is to review the clinical and radiologic findings of arthropathies that can present in athletes and be confused with internal derangement.

Recent advances in imaging in psoriatic arthritis

The recent introduction of effective therapies in psoriatic arthritis (PsA) has increased the demand for efficient tools for diagnosis, monitoring and prognostication of PsA, and has caused an increased research effort within imaging in this disease. The clinical appearance of PsA is very diverse, involving the spine, sacroiliac joints, peripheral joints and/or entheses, and accordingly imaging findings vary. In the present paper, we present a review of the recent advances in imaging in PsA, focusing primarily on ultrasonography and magnetic resonance imaging of peripheral disease manifestations.

Knee enthesitis and synovitis on magnetic resonance imaging in patients with psoriasis without arthritic symptoms

OBJECTIVE

This case-control study was designed to evaluate magnetic resonance imaging (MRI) findings of knee joints in patients with psoriasis without clinical peripheral or axial joint involvement, and to correlate MRI findings with disease and demographic variables.

METHODS

In total 48 patients with psoriasis and no clinical evidence of synovitis or enthesitis in any peripheral or axial joints were enrolled. A random sample of 20 healthy subjects without knee or other joint complaints and matched for age and sex served as controls. All patients and controls underwent enhanced MRI studies of both knee joints, and MRI findings were compared.

RESULTS

Among 48 patients (96 knees), a total of 90 entheseal lesions were detected, with no enthesitis in 2 cases (6.3%). Signs of continuing inflammation bilaterally were frequently found: soft tissue edema (STE; n = 52), bone marrow edema (BME; n = 20), perientheseal BME (n = 3), cartilaginous erosions (n = 42), and bone erosions (n = 27). In controls, 2 (10%) subjects had BME and another 5 (25%) showed cartilaginous erosions. None showed evidence of enthesitis. Significant correlations were observed between the number of entheseal lesions of both knees vs STE (present vs absent; r = 0.314, p = 0.030) and STE (number of lesions; r = 0.351, p = 0.014). Enthesitis (unilateral vs bilateral) was significantly and positively correlated with STE (r = 0.304, p = 0.036), cartilaginous erosions (r = 0.304, p = 0.036), and villous projections (r = 0.347, p = 0.016).

CONCLUSION

Subclinical synovitis and enthesitis are frequently found in the knee joint of patients with psoriasis. These may be an early sign of psoriatic arthritis.

Magnetic Resonance Imaging in Psoriatic Arthritis — Update on Current Status and Future Perspectives: A Report from the GRAPPA 2010 Annual Meeting

The potential of magnetic resonance imaging (MRI) for use in clinical practice and research has gained increasing interest over the last decade. International collaborative initiatives from GRAPPA (Group for Research and Assessment of Psoriasis and Psoriatic Arthritis) and/or OMERACT (Outcome Measures in Rheumatology) may contribute to facilitating research, identifying appropriate areas for use, and reaching consensus on the optimal examination technique. Accordingly, GRAPPA, a primary driver of international research in psoriasis and psoriatic arthritis (PsA), has focused on the current use and future development of MRI and other modern imaging modalities in PsA. This review, presented at the GRAPPA 2010 annual meeting, describes the current status of MRI in PsA, with a focus on its use in diagnosis, monitoring, and prediction of the disease course and treatment response. Important areas for future research are also outlined.

Ultrasonography and color Doppler of proximal gluteal enthesitis in juvenile idiopathic arthritis: a descriptive study

BACKGROUND

The presence of enthesitis (insertional inflammation) in patients with juvenile idiopathic arthritis (JIA) is difficult to establish clinically and may influence classification and treatment of the disease. We used ultrasonography (US) and color Doppler (CD) imaging to detect enthesitis at the small and deep-seated proximal insertion of the gluteus medius fascia on the posterior iliac crest where clinical diagnosis is difficult. The findings in JIA patients were compared with those obtained in healthy controls and with the patients' MRI results.

METHODS

Seventy-six proximal gluteus medius insertions were studied clinically (tenderness to palpation of the posterior iliac crest) and by US and CD (echogenicity, thickness, hyperemia) in 38 patients with JIA and in 38 healthy controls, respectively (median age 13 years, range 7-18 years). In addition, an additional MRI examination of the sacroiliac joints and iliac crests was performed in all patients.

RESULTS

In patients with focal, palpable tenderness, US detected decreased echogenicity of the entheses in 53% of the iliac crests (bilateral in 37% and unilateral in 32%). US also revealed significantly thicker entheses in JIA patients compared to healthy controls (p < 0.003 left side, p < 0.001 right side). There was no significant difference in thickness between the left and right sides in individual subjects. Hyperemia was detected by CD in 37% (28/76) of the iliac crests and by contrast-enhanced MRI in 12% (6/50).

CONCLUSIONS

According to US, the gluteus medius insertion was thicker in JIA patients than in controls, and it was hypoechoic (enthesitis) in about half of the patients. These findings may represent chronic, inactive disease in some of the patients, because there was only limited Doppler flow and MRI contrast enhancement. The present study indicates that US can be useful as an adjunct to clinical examination for improved assessment of enthesitis in JIA. This may influence disease classification, ambition to treat, and choice of treatment regimen.

Magnetic resonance imaging of inflammatory arthropathies of peripheral joints

As the treatment of inflammatory arthropathies has advanced with new therapies that can slow or even halt the development of disabling disease, early and accurate diagnosis has become imperative. Magnetic resonance (MR) imaging has proved to be very sensitive in the detection of erosions, but more importantly, it can demonstrate pre-erosive changes. Detection of synovitis and edema-like bone marrow lesions for initial diagnosis and as an indicator of disease progression can provide crucial information leading to therapeutic interventions before permanent joint damage occurs. Understanding the characteristic intra-articular and extra-articular MR imaging findings of the inflammatory arthritides allows the radiologist to provide appropriate consultations in the care of these patients. The MR appearances of both intra-articular and extra-articular findings of inflammatory arthritis are presented. Despite the advances in imaging, however, many of the MR findings remain nonspecific, and radiologists must avoid overdiagnosis by synthesizing all of the clinical information available into their interpretations.