Reliability of high-resolution ultrasonography in the assessment of Achilles tendon enthesopathy in seronegative spondyloarthropathies

Hematological indices in psoriatic enthesopathy: relation to clinical and ultrasound evaluation

BACKGROUND

Enthesopathy is considered a crucial aspect of assessment and outcome in psoriatic arthritis (PsA). Musculoskeletal ultrasound (MSUS) is a critical tool for accurately detecting enthesitis. Recent research focuses on identifying simple biomarkers for detecting and monitoring psoriatic enthesopathy. Red cell distribution width (RDW), mean platelet volume (MPV), and neutrophil/lymphocyte ratio (NLR) are components of a complete blood count (CBC) and are reliable bio-inflammatory markers in various rheumatic diseases.

AIM OF WORK

To measure MPV, RDW, and NLR in psoriatic enthesopathy and determine their relationship to disease activity and MSUS findings.

PATIENTS AND METHODS

This study focused on 30 people with psoriatic arthritis (PsA) as per CASPAR criteria, along with 20 control subjects. Enthesopathy was evaluated clinically using the Leeds Enthesitis Index (LEI). The modified Disease Activity Index of Psoriatic Arthritis (DAPSA28) was calculated, and RDW, MPV, NLR, CRP, and ESR were measured. Each enthesis in LEI was radiologically assessed using plain radiography and MSUS according to OMERACT definitions.

RESULTS

There was a significant relationship between clinical tenderness, the presence of enthesophytes on plain radiography, and MSUS findings at entheses sites (p < 0.001 for each). Psoriatic patients had higher levels of RDW and MPV (p < 0.001 and 0.01, respectively) than controls, with no significant differences in NLR (p = 0.189) between the two groups. RDW and MPV levels were positively correlated with the DAPSA28 score.

CONCLUSION

Monitoring PsA disease activity can be improved by considering RDW and MPV as reliable indicators and using them to screen for psoriatic enthesopathy with MSUS indices. Key points • Clinically identifying enthesitis in patients with PsA can be challenging. Imaging MSUS indices hold promise for objective analysis, but there is no consensus on which indices to use in clinical trials and daily practice. • Patients with psoriatic enthesopathy have higher RDW and MPV levels, which are positively correlated with DAPSA28 score. • RDW and MPV can be considered in the turn of improved screening of psoriatic enthesopathy with MSUS scores.

A New Quantitative Tool for the Ultrasonographic Assessment of Tendons: A Reliability and Validity Study on the Patellar Tendon

Ultrasound is widely used for tendon assessment due to its safety, affordability, and portability, but its subjective nature poses challenges. This study aimed to develop a new quantitative analysis tool based on artificial intelligence to identify statistical patterns of healthy and pathological tendons. Furthermore, we aimed to validate this new tool by comparing it to experts' subjective assessments. A pilot database including healthy controls and patients with patellar tendinopathy was constructed, involving 14 participants with asymptomatic (n = 7) and symptomatic (n = 7) patellar tendons. Ultrasonographic images were assessed twice, utilizing both the new quantitative tool and the subjective scoring method applied by an expert across five regions of interest. The database contained 61 variables per image. The robustness of the clinical and quantitative assessments was tested via reliability analyses. Lastly, the prediction accuracy of the quantitative features was tested via cross-validated generalized linear mixed-effects logistic regressions. These analyses showed high reliability for quantitative variables related to "Bone" and "Quality", with ICCs above 0.75. The ICCs for "Edges" and "Thickness" varied but mostly exceeded 0.75. The results of this study show that certain quantitative variables are capable of predicting an expert's subjective assessment with generally high cross-validated AUC scores. A new quantitative tool for the ultrasonographic assessment of the tendon was designed. This system is shown to be a reliable and valid method for evaluating the patellar tendon structure.

Entheseal Involvement in Spondyloarthritis (SpA) and Gout: An Ultrasound Comparative Study

Objective

To compare the assessment of entheses in subjects with spondyloarthritis (SpA) with patients with gout by the Madrid Sonographic Enthesis Index (MASEI).

Method

This cross-sectional study includes videos of entheses evaluated by ultrasound (US) of 30 patients with SpA diagnosed according to the ASAS criteria and 30 patients with gout established by the presence of monosodium urate crystals. Entheses were evaluated for MASEI in 2 Institutes located in two different countries. Demographic and clinical data were registered. Total MASEI score, MASEI-inflammatory, and MASEI-chronic damage were analyzed. Comparisons between groups were obtained by chi-square test and Student's t-test. An inter-reading US reliability was realized.

Results

Patients with gout were older and had significantly more comorbidities than those with SpA. The total MASEI score was not significantly different among diseases (p = 0.07). MASEI-inflammatory was significantly more prevalent at the Achilles tendon in SpA, while the proximal patellar tendon was in gout. Power Doppler was higher in SpA compared to gout (p = 0.005). MASEI-chronic damage related to calcification/enthesophytes predominated in gout (p = 0.043), while calcaneal erosions did in SpA (p = 0.008). The inter-reader concordance was excellent (0.93, CI 95% 0.87–0.96, p = 0.001).

Conclusions

SpA and gout similarly involve entheses according to MASE, however, some inflammatory and chronic lesions differ significantly depending on the underlying disease and tendon scanned.

Enthesitis in Psoriatic Arthritis, the Sonographic Perspective

Purpose of Review

To provide an overview of the ultrasound (US) studies focusing on enthesitis in psoriatic arthritis (PsA).

Recent Findings

Last-generation US equipment has demonstrated the ability to detect subtle morphostructural and vascular abnormalities at entheseal level. US is able to identify pathologic changes in both “classical” (i.e., the site of attachment of tendons, ligaments, and joint capsules into the bone) and “functional” entheses (i.e., anatomical regions where tendons or ligaments wrap around bony pulleys).

Summary

US has the potential to be the first-line method in the assessment of enthesitis. In the present review we critically discussed the current definitions of US enthesitis, the scoring systems, and the main fields of application (i.e., the detection of enthesitis in PsA and psoriasis, the identification of different disease subsets, and the assessment of response to treatment).

Ultrasound definition of enthesitis in spondyloarthritis and psoriatic arthritis: arrival or starting point?

Enthesitis has a key role in the diagnosis, classification and management of patients with spondyloarthritis and psoriatic arthritis. Clinical assessment of enthesitis is known to be inaccurate mainly due to its poor specificity. In this context, ultrasound has the potential to improve the evaluation of enthesitis and, therefore, the management of patients with spondyloarthritis and psoriatic arthritis. In this viewpoint, we review the Outcome Measures in Rheumatology (OMERACT) definitions for ultrasound enthesitis, highlighting their current limits and potential implications on rheumatology research and clinical practice.

A Narrative Review of the Classification and Use of Diagnostic Ultrasound for Conditions of the Achilles Tendon

Enthesitis is a cardinal feature of spondyloarthropathies. The Achilles insertion on the calcaneus is a commonly evaluated enthesis located at the hindfoot, generally resulting in hindfoot pain and possible tendon enlargement. For decades, diagnosis of enthesitis was based upon patient history of hindfoot or posterior ankle pain and clinical examination revealing tenderness and/or enlargement at the site of the tendon insertion. However, not all hindfoot or posterior ankle symptoms are related to enthesitis. Advanced imaging, including magnetic resonance imaging (MRI) and ultrasound (US), has allowed for more precise evaluation of hindfoot and posterior ankle conditions. Use of US in diagnosis has helped confirm some of these cases but also identified other conditions that may have otherwise been misclassified without use of advanced imaging diagnostics. Conditions that may result in hindfoot and posterior ankle symptoms related to the Achilles tendon include enthesitis (which can include retrocalcaneal bursitis and insertional tendonopathy), midportion tendonopathy, paratenonopathy, superficial calcaneal bursitis, calcaneal ossification (Haglund deformity), and calcific tendonopathy. With regard to classification of these conditions, much of the existing literature uses confusing nomenclature to describe conditions in this region of the body. Some terminology may imply inflammation when in fact there may be none. A more uniform approach to classifying these conditions based off anatomic location, symptoms, clinical findings, and histopathology is needed. There has been much debate regarding appropriate use of tendonitis when there is no true inflammation, calling instead for use of the terms tendinosis or tendonopathy. To date, there has not been clear examination of a similar overuse of the term enthesitis in conditions where there is no underlying inflammation, thus raising the need for more comprehensive taxonomy.

[CME Sonography 93: Ultrasound of the Enthesis - Not Every "Enthesitis" Signals a Spondyloarthritis]

CME Sonography 93: Ultrasound of the Enthesis - Not Every "Enthesitis" Signals a Spondyloarthritis Abstract. In this CME we will focus on the ultrasound anatomy of the enthesis. In addition, we describe the terms enthesopathy and enthesitis and discuss related differential diagnostic considerations. It is important to know all the diseases that can manifest themselves at the enthesis, so that diagnoses can be made, and patients classified correctly. At this point it is worth mentioning that the findings of enthesitis do not necessarily need to be associated with spondylarthritis.

Ultrasonographic evaluation of Achilles tendon: Is there any difference between ankylosing spondylitis, non-radiographic axial spondyloarthropathy and controls?

PURPOSE

The aim is to evaluate Achilles tendon enthesopathy with ultrasound (US) in ankylosing spondylitis (AS) and non-radiographic axial SpA (nr-axSpA) patients and controls, and compare these groups in terms of associations between disease activity parameters and ultrasonographic Achilles enthesitis signs.

METHODS

A total of 24 AS and 20 nr-axSpA patients fulfilling the Assessment in Spondyloarthritis International Working Group criteria for axSpA and 30 controls were enrolled. Demographic characteristics, erythrocyte sedimentation rate, C-reactive protein (CRP), human leukocyte antigen (HLA)-B27, Bath AS Disease Activity Index, Bath AS Functional Index, Bath AS Metrology Index, Maastricht AS Enthesitis Score (MASES), AS Disease Activity Score-CRP, modified Stoke AS Spine Score (m-SASSS) scores and ultrasonographic findings were noted.

RESULTS

HLA-B27 positivity, extra-articular and peripheral involvement, disease activity, functional status, mean m-SASSS, ultrasonographic gray scale (GS) and total scores were similar between AS and nr-axSpA groups. In GS, tendon echotexture scores were significantly different across all groups (0.812 ± 0.384 in AS, 0.575 ± 0.466 in nr-axSpA, 0.017 ± 0.091 in controls; P < .001). Entheseal calcification scores were similar in AS and nr-axSpA patients, and higher than controls (P = .001). Bone profile scores were similar in patients with AS and nr-axSpA, and higher than controls (P = .010). When the correlations between US findings and disease activity and functional status were considered, power Doppler US (PDUS) and MASES total scores were positively correlated in the AS group (P = .045; r = .41).

CONCLUSION

AS and nr-axSpA patients were found to be similar in various clinical, functional, and US findings indicating that these 2 entities are different phenotypic reflections of the same disease spectrum. The positive correlation between PDUS and MASES scores in AS patients substantiate the performance of MASES in evaluation of entheseal activity.

[Usefulness and reliabitlity of musculoskeletal point of care ultrasound in family practice (1): Knee, shoulder and enthesis]

Musculoskeletal ultrasound (MSU) is a technique which has been extended to practically all medical specialties that comprise this pathology. Family Doctor (FD) has not been away from this process due to its great wide of competences, using it in different scenarios inside his common practice in which he can get profits in a reliable, efficient and effective way. Ultrasound equipment incorporation in Primary Care (PC) centers is an increasing reality, contributing to high ranges of accessibility, immediacy and clinic handle capability, and thus, together with the high prevalence in this area in locomotor apparatus, turns MSU into an strategic action for the improvement of the resolving capacity and consequently for the health care. To ensure proficiency among users, it's being necessary to define the benefits and potential risks its use can cause, as well as its different scenarios, avoiding unnecessary explorations and optimizing the investment of this resource at PC level. This paper pretends to summarize the state of the art of the musculoskeletal ultrasound and its benefits for the FD into this efficient and effective scenarios.

Entheseal involvement in patients with systemic lupus erythematosus: an ultrasound study

Objectives

The main objective of this study is to explore the prevalence and distribution of entheseal US changes in a cohort of SLE patients, taking as controls a group including both PsA patients and healthy subjects. The secondary objective is to investigate the correlation between the US findings and the clinical and serological data in SLE patients.

Methods

Clinical and US assessment of quadriceps, patellar and Achilles tendons, and plantar fascia entheses were performed by independent rheumatologists on 65 patients with SLE, 50 patients with PsA and 50 healthy subjects. US findings were identified according to the OMERACT definitions. In SLE patients, the correlation between the US changes and the clinical and laboratory findings was evaluated.

Results

US revealed one or more abnormalities in at least one enthesis in 44 out of 65 SLE patients (67.7%), 47 out of 50 PsA patients (94.0%) and 22 out of 50 healthy subjects (44.0%). In SLE patients, US findings indicating active inflammation were significantly more frequently detected than in healthy subjects (P < 0.001). The distal enthesis of the patellar tendon was the most commonly involved. The presence of power Doppler signal at the enthesis was an independent predictor of SLE disease activity (SLEDAI-2k P < 0.001, β = 0.52; musculoskeletal-BILAG P < 0.001, β = 0.56).

Conclusion

The burden of entheseal sonographic changes was significantly higher in SLE patients than in healthy subjects, especially as regards active inflammation. The presence of power Doppler signal at the enthesis may represent a potential biomarker of SLE disease activity.

Remission in psoriatic arthritis-where are we now?

Advances in treatments and treatment strategies for PsA have led to many patients responding well to management of their disease, and targeting remission as a treatment goal is now a possibility. Treat to target is a strategy aimed at maximizing benefit, irrespective of the type of medication used, by monitoring disease activity and using it to guide therapy. The measurement of response to treatment has been the subject of wide discussions among experts for some time, and many instruments exist. Comparisons of the different measures and their different strengths and weaknesses is ongoing. The impact of modern imaging techniques on monitoring disease progression is also evolving, and advanced techniques using both MRI and US have the potential to improve management of PsA through identification of risk factors for poor prognosis as well as accurate assessment of inflammation and damage, including subclinical disease. Increased understanding of the pathways that drive the pathogenesis of PsA will be key to identifying specific biomarkers for the disease and developing effective treatment strategies. Targets for response, considerations for use of a treat to target strategy in PsA, different imaging techniques and serological aspects of remission are all discussed in this review, and areas for further research are identified.

Achilles enthesitis defined by ultrasound is not associated with clinical enthesitis in patients with psoriatic arthritis

Objective

To compare clinical and ultrasonographic (US) evaluation of Achilles enthesitis in patients with psoriatic arthritis (PsA).

Methods

The Achilles insertion of outpatients with PsA was examined by clinical assessment of tenderness and US evaluation of (1) inflammatory activity (defined as the presence of power Doppler signal, tendon thickening and/or hypoechogenicity) and (2) structural damage (defined as the presence of erosions, calcifications and/or enthesophytes). Univariate and multivariate logistic regression analyses were performed0.4 to explore the associations between clinical characteristics and US scores.

Results

282 Achilles tendons in 141 patients with PsA were assessed. Mean (SD) age was 52.4 (10.2) years, disease duration 9.5 (6.6) years and 50.4% were females. Palpatory tenderness was found in 88 (31.2%), US-verified inflammatory activity in 46 (16.3%) and structural damage in 148 (52.5%) of the Achilles. Total US scores, as well as their components, were similar for patients with and without palpatory tenderness. None of the clinical characteristics were associated with inflammatory activity. Age, body mass index (BMI), regular physical exercise and current use of biological disease-modifying antirheumatic drugs (bDMARDs) were associated with structural damage.

Conclusion

There appears to be a lack of association between clinical and US signs of Achilles enthesitis in PsA. Age, BMI, regular physical exercise and current use of bDMARDs were associated with structural damage on US.

Ultrasound Characteristics of the Achilles Tendon in Tophaceous Gout: A Comparison with Age- and Sex-matched Controls

OBJECTIVE

To investigate the frequency and distribution of characteristics of the Achilles tendon (AT) in people with tophaceous gout using musculoskeletal ultrasound (US).

METHODS

Twenty-four participants with tophaceous gout and 24 age- and sex-matched controls without gout or other arthritis were recruited. All participants underwent a greyscale and power Doppler US examination. The AT was divided into 3 anatomical zones (insertion, pre-insertional, and proximal to the mid-section). The following US characteristics were assessed: tophus, tendon echogenicity, tendon vascularity, tendon morphology, entheseal characteristics, bursal morphology, and calcaneal bone profile.

RESULTS

The majority of the participants with tophaceous gout were middle-aged men (n = 22, 92%) predominately of European ethnicity (n = 14, 58%). Tophus deposition was observed in 73% (n = 35) of tendons in those with gout and in none of the controls (p < 0.01). Intratendinous hyperechoic spots (p < 0.01) and intratendinous power Doppler signal (p < 0.01) were more frequent in participants with gout compared to controls. High prevalence of entheseal calcifications, calcaneal bone cortex irregularities, and calcaneal enthesophytes were observed in both gout participants and controls, without differences between groups. Intratendinous structural damage was rare. Hyperechoic spots were significantly more common at the insertion compared to the zone proximal to the mid-section (p < 0.01), but between-zone differences were not observed for other features.

CONCLUSION

US features of urate deposition, tophus, and vascularization are present throughout the AT in patients with tophaceous gout. Despite crystal deposition, intratendinous structural changes are infrequent. Many characteristics observed in the AT in people with tophaceous gout, particularly at the calcaneal enthesis, are not disease-specific.

Ultrasonography assessment of heel entheses in patients with spondyloarthritis: a comparative study with magnetic resonance imaging and conventional radiography

The aim of the present study was to determine the agreement between ultrasonography (US), magnetic resonance imaging (MRI), and conventional radiography (CR) in the detection of findings indicative of enthesopathy in spondyloarthritis (SpA) patients. A cross-sectional study was performed in 40 SpA patients. Heel entheses (Achilles tendon and plantar fascia) were bilaterally examined by US, MRI, and CR. The three imaging modalities were carried out by three independent operators blinded to the other imaging modality data. Soft tissue abnormalities indicative of enthesopathy as thickening, structural changes, and bursitis were assessed by both US and MRI, and cortical bone abnormalities indicative of enthesopathy as erosions and enthesophytes were assessed by the three imaging modalities. The unweighted kappa values between US and MRI were 0.80, 0.66, 0.69, 0.70, and 0.70 for thickening, structural changes, bursitis, enthesophytes, and bone erosions, respectively. With respect to the detection of enthesophytes, the unweighted kappa values between CR and both US and MRI were 0.78 and 0.76, respectively. At last, for the recognition of bone erosions, the unweighted kappa values between CR and both US and MRI were 0.38 and 0.45, respectively. Using MRI as standard reference method, US was more sensitive with respect to CR revealing bone erosions. The present study provides evidence about the high overall agreement between US and MRI for all abnormal comparable findings at entheseal level and between US, MRI, and CR for the detection of enthesophytes in SpA patients.

Recommendations for the Use of Ultrasound and Magnetic Resonance in Patients With Spondyloarthritis, Including Psoriatic Arthritis, and Patients With Juvenile Idiopathic Arthritis

OBJECTIVE

To develop evidence-based recommendations on the use of ultrasound (US) and magnetic resonance imaging in patients with spondyloarthritis, including psoriatic arthritis, and juvenile idiopathic arthritis.

METHODS

Recommendations were generated following a nominal group technique. A panel of experts (15 rheumatologists and 3 radiologists) was established in the first panel meeting to define the scope and purpose of the consensus document, as well as chapters, potential recommendations and systematic literature reviews (we used and updated those from previous EULAR documents). A first draft of recommendations and text was generated. Then, an electronic Delphi process (2 rounds) was carried out. Recommendations were voted from 1 (total disagreement) to 10 (total agreement). We defined agreement if at least 70% of participants voted≥7. The level of evidence and grade or recommendation was assessed using the Oxford Centre for Evidence Based Medicine levels of evidence. The full text was circulated and reviewed by the panel. The consensus was coordinated by an expert methodologist.

RESULTS

A total of 12 recommendations were proposed for each disease. They include, along with explanations of the validity of US and magnetic resonance imaging regarding inflammation and damage detection, diagnosis, prediction (structural damage progression, flare, treatment response, etc.), monitoring and the use of US guided injections/biopsies.

CONCLUSIONS

These recommendations will help clinicians use US and magnetic resonance imaging in patients with spondyloarthritis and juvenile idiopathic arthritis.

The effect of foot position on Power Doppler Ultrasound grading of Achilles enthesitis

The aim of this study was to determine whether foot position could modify power Doppler grading in evaluation of the Achilles enthesis. Eighteen patients with clinical Achilles enthesitis were studied with power Doppler ultrasound (PDUS) in five different positions of the foot: active and passive dorsiflexion, neutral position, active and passive plantar flexion. The Doppler signal was graded in any position and compared with the others. The Doppler signal was higher with the foot in plantar flexion and decreased gradually, sometimes till to disappear, while increasing dorsiflexion. The Doppler signal was always less during the active keeping of the position of the joint, than during the passive. The PDUS examination of the Achilles enthesis should be performed also with the foot in passive plantar flexion, in order not to underestimate the degree of vascularization.

Discriminant validity study of Achilles enthesis ultrasound

OBJECTIVE

We want to know if the ultrasound examination of the Achilles tendon in spondyloarthritis is different compared to other rheumatic diseases.

MATERIAL AND METHODS

We studied 97 patients divided into five groups: rheumatoid arthritis, spondyloarthritis, gout, chondrocalcinosis and osteoarthritis, exploring six elementary lesions in 194 Achilles entheses examined.

RESULTS

In our study the total index ultrasonographic Achilles is higher in spondyloarthritis with significant differences. The worst elementary spondyloarthritis lesions for discriminations against other pathologies were calcification.

CONCLUSIONS

This study aims to demonstrate the discriminant validity of Achilles enthesitis observed by ultrasound in spondyloarthritis compared with other rheumatic diseases that may also have ultrasound abnormalities such enthesis level.

Is entheses ultrasound reliable? A reading Latin American exercise

The objective of this study is to evaluate inter-reader entheses ultrasound (US) reliability and the influence of the type of image or degree of sonographer experience on US reliability in patients with spondyloarthritis (SpA). Eighteen Latin American ultrasonographers with different experience took part in an US reading exercise evaluating 60 entheseal images (50 % static images and 50 % videos) from healthy controls and SpA patients. The following sonographic lesions were assessed: structure, thickness, bone proliferation/tendon calcification, erosions, bursitis, and Doppler signal. Another group of three experts with significant experience in entheses US read all images too. Inter-reader reliability among participants and experts was calculated by the Cohen's kappa coefficient. Thresholds for kappa values were <0.2 poor, 0.21-0.4 fair, 0.41-0.6 moderate, 0.61-0.8 good, and 0.81-1 excellent. Furthermore, the results for the expert group were stratified based on the type of image. Kappa correlation coefficients among participants, showed variability depending on the type of lesion, being fair for structure and thickness, moderate for calcifications, erosions, and bursitis, and excellent for Doppler signal. Inter-reader reliability among experts was higher, being moderate for structure and thickness, good for calcifications and bursitis, and excellent for erosions and Doppler. Inter-reader reliability for assessing calcification and structure using static images was significantly higher than for videos. Overall inter-reader reliability for assessing entheses by US in SpA is moderate to excellent for most of the lesions. However, special training seems fundamental to achieve better inter-reader reliability. Moreover, the type of image influenced these results, where evaluation of entheses by videos was more difficult than by static images.

Enthesopathies and enthesitis. Part 1. Etiopathogenesis

The pathologies of tendon and ligament attachments are called enthesopathies. One of its types is enthesitis which is a characteristic sign of peripheral spondyloarthropathy. Clinical diagnosis of enthesitis is based on rather non-specific clinical signs and results of laboratory tests. Imaging examinations are highly promising. Numerous publications prove that enthesitis can be differentiated from other enthesopathic processes in an ultrasound examination or magnetic resonance imaging. However, some reports indicate the lack of histological criteria, specific immunological changes and features in imaging examinations that would allow the clinical diagnosis of enthesitis to be confirmed. The first part of the publication presents theories on the etiopathogenesis of enthesopathies: inflammatory, mechanical, autoimmune, genetic and associated with the synovio-entheseal complex, as well as theories on the formation of enthesophytes: inflammatory, molecular and mechanical. The second part of the paper is a review of the state-of-the-art on the ability of imaging examinations to diagnose enthesitis. It indicates that none of the criteria of inflammation used in imaging medicine is specific for this pathology. As enthesitis may be the only symptom of early spondyloarthropathy (particularly in patients with absent HLA-B27 receptor), the lack of its unambiguous picture in ultrasound and magnetic resonance scans prompts the search for other signs characteristic of this disease and more specific markers in imaging in order to establish diagnosis as early as possible.

Defining enthesitis in spondyloarthritis by ultrasound: results of a Delphi process and of a reliability reading exercise

OBJECTIVE

To standardize ultrasound (US) in enthesitis.

METHODS

An initial Delphi exercise was undertaken to define US-detected enthesitis and its core components. These definitions were subsequently tested on static images taken from spondyloarthritis patients in order to evaluate their reliability.

RESULTS

Excellent agreement (>80%) was obtained for including hypoechogenicity, increased thickness of the tendon insertion, calcifications, enthesophytes, erosions, and Doppler activity as core elementary lesions of US-detected enthesitis. US definitions were subsequently obtained for each elementary component. On static images, the intraobserver reliability showed a high degree of variability for the detection of elementary lesions, with kappa coefficients ranging from 0.13-1. The interobserver kappa values were variable, with the lowest kappa coefficient for enthesophytes (0.24) and the highest coefficient for Doppler activity at the enthesis (0.63).

CONCLUSION

This is the first consensus-based US definition of enthesitis and its elementary components and the first step performed to ensure a higher degree of homogeneity and comparability of results between studies and in daily clinical work.

Psoriatic arthritis and nail changes: exploring the relationship

OBJECTIVE

Psoriatic arthritis (PsA) has a diverse range of clinical manifestations, both articular and extra-articular. Although the association of PsA with skin changes is well established, the relationship of PsA with psoriatic nail changes remains relatively unexplored.

METHODS

This report reviews the current literature surrounding the association of PsA with nail changes. A review of the literature was completed using PubMed, MEDLINE, and EMBASE in September 2013, encompassing years 1964-2012.

RESULTS

A total of 21 articles were reviewed. On average, 66% [standard deviation (SD) 17.7] of PsA patients had nail changes. The type of nail changes and their associations varied widely between studies.

CONCLUSIONS

Studies of nail changes in PsA are highly variable with a wide range of results. Given the variability of results that were observed in this review, our recommendations are that further large studies on nail changes in patients with PsA should be conducted.

Role of sonography and magnetic resonance imaging in detecting deltoideal acromial enthesopathy: an early finding in the diagnosis of spondyloarthritis and an under-recognized cause of posterior shoulder pain

The acromial origin of the deltoid is a target structure of ankylosing spondylitis and related spondyloarthritis, which are often overlooked and underdiagnosed as causes of posterior shoulder pain. The objective of this article is to review the roles of sonography and magnetic resonance imaging in detecting deltoideal acromial enthesopathy and their importance for optimizing management in individuals with posterior shoulder pain. Adequate awareness of such enthesopathy as a potential manifestation of inflammatory rheumatic disorders is critical for early diagnosis of spondyloarthritis.

Value of contrast-enhanced ultrasonography for the detection and quantification of enthesitis vascularization in patients with spondyloarthritis

OBJECTIVE

To evaluate if contrast-enhanced ultrasound (CEUS) can improve the detection and quantification of the vascularization of mild enthesitis in spondyloarthritis (SpA) and to evaluate the influence of nonsteroidal antiinflammatory drugs (NSAIDs) on such detection.

METHODS

Fourteen patients with mildly active SpA were evaluated at 3 consecutive visits: at baseline while undergoing NSAID treatment (V1), after 1 week of stopping NSAIDs (V2), and after 1 week of resuming NSAIDs (V3). At each visit, enthesitis was evaluated clinically and by power Doppler US (PDUS). A selected enthesis with a doubtful PDUS vascularization signal was studied by CEUS in 2 steps: (1) using a dedicated technology that preserves microbubbles (Contrast Tuned Imaging technology [CEUS-CnTI]) and (2) using high PD (CEUS-PD) to destroy microbubbles. A linear mixed model statistical analysis, taking visits and contrast agent as fixed factors and the patient as a random factor, was used.

RESULTS

Disease activity and PDUS findings increased between V1 and V2 and then decreased between V2 and V3. As compared with PDUS alone, CEUS-PD and CEUS-CnTI each detected 1 supplementary vascularized enthesis at V1, CEUS-PD detected 1 vascularized enthesis and CEUS-CnTI detected 3 vascularized entheses at V2, and CEUS-PD and CEUS-CnTI each detected 2 vascularized entheses at V3. The mean inflammation score was increased by the use of CEUS (P = 0.04). This score increased between V1 and V2 (P = 0.03 by CEUS-PD and P = 0.01 by CEUS-CnTI) and decreased between V2 and V3.

CONCLUSION

CEUS improved the detection of enthesitis in SpA patients by confirming all doubtful enthesitis signals and confirming the absence of enthesis vascularization. The use of NSAIDs influenced the detection of vascularization.

Sonographic measurement of Achilles tendon thickness in seronegative spondyloarthropathies

OBJECTIVE

To define the best cut-off value for identifying Achilles tendon thickening using ultrasound (US) in patients with spondyloarthropathies (SpA) and to assess its diagnostic utility in comparison with different cut-off values used in the literature.

MATERIAL AND METHODS

One-hundred and one subjects (55 SpA patients and 46 age and body mass index ((BMI)-matched healthy controls (HC)) were investigated. US was performed using a MyLab70 US system (Esaote Biomedica, Genoa, Italy) with a linear probe (6-18 MHz). Three images per Achilles enthesis were stored and the antero-posterior thickness of the enthesis was measured at the level of the Achilles tendon deeper margin insertion into the calcaneal bone on the longitudinal median scan. The best cut-off value for each gender was determined by ROC curve analysis and compared to the other cut-off values in the literature: 1) 5.29 mm for both genders, and 2) 5.5 mm for females and 6.2 mm for males. The number of measurements exceeding the cut-off values as well as sensitivity (SE), specificity (SP), positive (PPV) and negative (NPV) predictive values were calculated.

RESULTS

A significant difference was observed for Achilles enthesis thickness between genders (mean±SD: 4.6±0.7 mm in males vs. 4.0±0.8 mm in females, p<0.00) and between SpA patients and HC (mean±SD: 4.4±0.8 mm in SpA patients vs. 4.0±0.8 mm in HC, p<0.001). The ROC curve analysis revealed the best cut-off value to be 3.7 mm for females and 4.8 mm for males (SE: 43-70%, SP: 59-85%, PPV: 66-79%, NPV: 54-63%). Previously reported cut-off values were found to have high SP (91-98%) but very low SE (2-11%).

CONCLUSION

Achilles tendon thickness differs between genders; thus, it is crucial to refer to normal values that are specific for gender. High cut-off values, as previously suggested, showed very low SE in the current study. When Achilles enthesis thickening is used for the purpose of screening enthesitis in SpA patients, a lower cut-off value has a higher SE with slightly worse SP, PPV and NPVs.

Usefulness of ultrasonography in the assessment of peripheral enthesis in spondyloarthritis

Enthesitis is one of the characteristic etiopathogenic manifestations of spondyloarthritis. However, in clinical practice, its presence often goes unnoticed because of the lack of precision and sensitivity of physical examination to detect it. Viable, valid and reliable imaging tests are needed for early diagnosis, as well as a good sensitivity to change to monitor therapeutic response. In this paper we review the most relevant aspects of current knowledge of the enthesis and discusses the validity of ultrasound for assessing enthesitis in spondyloarthritis and its sensitivity to change to monitor therapeutic response.

MRI and ultrasonography for diagnosis and monitoring of psoriatic arthritis

Imaging techniques such as magnetic resonance imaging (MRI) and ultrasound (US) have been increasingly used in psoriatic arthritis (PsA) providing additional clues to the pathogenesis of this peripheral, axial and dermatologic disease. This has improved our understanding of the disease and can be used to aid diagnosis and then to follow outcomes of treatment. Both imaging modalities have highlighted the differing involvement of PsA when compared with rheumatoid arthritis (RA) with a significant burden of entheseal disease, flexor tenosynovitis (occurring alone or as part of dactylitis) and other extra-capsular inflammatory changes. MRI scanning has also highlighted the link between the nail and the distal interphalangeal (DIP) joint confirming previous clinical observations. Imaging studies in psoriasis patients have discovered a high level of subclinical inflammatory change but the clinical importance of such findings has not yet been defined. The potential use of MRI and US to monitor treatment outcomes has encouraged research in this field. In MRI, the PsA MRI Score (PsAMRIS) has been developed with promising initial validation. In US, work is ongoing with the OMERACT group to define key pathologies and to develop scoring systems. A few scoring systems are available for enthesitis scoring using US which are further being developed and refined. Further improvements in technologies in both of these fields offer exciting possibilities for future research. New MRI techniques offer the chance to image previously 'dark' structures such as tendons which is key in spondyloarthritides (SpA). Sonoelastography may also improve our understanding of tendon involvement in SpA. Whole-body multi-joint MRI allows a 'snapshot' of inflammation in PsA including joints, entheses and spinal involvement. Three-dimensional US should improve reliability and comparability of US scoring reducing inter-operator variability. The latest machines offer real-time fusion imaging employing US machines with an in-built virtual navigator system linked to previous MRI acquisitions. All of these new techniques should aid our understanding of PsA and our ability to objectively measure response to therapy.

Role of diagnostic ultrasound in the assessment of musculoskeletal diseases

The wide availability and recent improvement in technology coupled with portability, low cost and safety makes ultrasound the first choice imaging investigation for the evaluation of musculoskeletal diseases. Diagnostic use of ultrasound findings is greatly enhanced by knowledge of the clinical presentation. Conversely, ultrasound skills with its prerequisite anatomical knowledge make the clinical diagnosis more precise and reduce uncertainty in the choice of therapy. Therefore, it is essential for rheumatologists to acquire ultrasonography skills in order to improve patient care. Ultrasound examination provides an excellent opportunity for patient education and to explain the rationale for therapy. This review summarizes the indications for musculoskeletal ultrasound and describes its role in diagnosis, monitoring and prognosis.

Quantitative MRI measurements of the Achilles tendon in spondyloarthritis using ultrashort echo times

OBJECTIVES

Tendon involvement is common in spondyloarthritis. The MRI signal from the Achilles tendon has been used to quantify mechanical tendinopathy; however, conventional MRI is limited by the short T(2) of normal tendon. Short and ultrashort echo time (UTE) MRI have the potential to better measure signal intensity reflecting changes in T(2) or gadolinium enhancement. Furthermore, UTE images could be used for normalisation to reduce variability. The aim of this work was to investigate such techniques in patients with spondyloarthritis (SpA).

METHODS

The Achilles tendons of 14 healthy volunteers and 24 patients with symptomatic spondyloarthritis were studied. Combined UTE (TE=0.07 ms) and gradient echo (TE=4.9 ms) images were acquired before and after intravenous gadolinium together with pre-contrast gradient echo images (TE=2 ms). The signal intensity from a region of interest in the Achilles tendon above the calcaneus was measured. The relative enhancement at echo times of 0.07 ms (RE(0.1)) and 4.9 ms (RE(5)) were calculated. The ratios of the signal intensities from both 4.9 ms and 2 ms gradient echo images to the signal intensity from the UTE image were calculated (RTE(5) and RTE(2) respectively).

RESULTS

Interobserver intraclass correlation coefficients were excellent (≥0.97). The contrast-to-noise ratio was higher for enhancement on UTE images than on gradient echo images. RE(0.1), RTE(5) and RTE(2) were significantly higher in SpA patients than controls.

CONCLUSION

Signal intensity ratios using UTE images allow quantitative measurements to be made which are sensitive to tendon T(2) or contrast enhancement and which are increased in spondyloarthritis. They therefore have the potential for use as measures of tendon disease in spondyloarthritis.

[Present and future of echography in spondyloarthritis]

Today ultrasound in spondyloarthritis is being developed in three main areas. Joint ultrasound is similar to that described in rheumatoid arthritis and other synovitis, with extensive literature on the matter. Enthesis ultrasound has a growing number of publications that describe the main elementary lesions. Several ultrasound enthesis scores have been developed that provide an overall view of the patient status and this information is useful both in the field of diagnosis and in assessing disease activity. The sacroiliac joints have also received attention and the published sensitivity and specificity could be useful in clinical practice. The future is unknown, but ultrasound has many possibilities that include improving the reliability, the incorporation of enthesis ultrasound assessment to the diagnostic classification criteria as well as the likelyhood developing simplified scores.

Reproducibility of sonographic measurement of thickness and echogenicity of the plantar fascia

BACKGROUND

To evaluate the intra- and interrater reliability of ultrasonographic measurements of the thickness and echogenicity of the plantar fascia.

METHODS

Eleven patients (20 feet), who complained of inferior heel pain, and 26 volunteers (52 feet) were enrolled. Two sonographers independently imaged the plantar fascia in both longitudinal and transverse planes. Volunteers were assessed twice to evaluate intrarater reliability. Quantitative evaluation of the echogenicity of the plantar fascia was performed by measuring the mean gray level of the region of interest using Digital Imaging and Communications in Medicine viewer software.

RESULTS

Sonographic evaluation of the thickness of the plantar fascia showed high reliability. Sonographic evaluations of the presence or absence of hypoechoic change in the plantar fascia showed surprisingly low agreement. The reliability of gray-scale evaluations appears to be much better than subjective judgments in the evaluation of echogenicity. Transverse scanning did not show any advantage in sonographic evaluation of the plantar fascia.

CONCLUSIONS

The reliability of sonographic examination of the thickness of the plantar fascia is high. Mean gray-level analysis of quantitative sonography can be used for the evaluation of echogenicity, which could reduce discrepancies in the interpretation of echogenicity by different sonographers. Longitudinal instead of transverse scanning is recommended for imaging the plantar fascia.

Ultrasound in the evaluation of enthesitis: status and perspectives

Introduction

An increasing number of studies have applied ultrasound to the evaluation of entheses in spondyloarthritis patients. However, no clear agreement exists on the definition of enthesitis, on the number and choice of entheses to examine and on ultrasound technique, which may all affect the results of the examination. The objectives of this study were to first determine the level of homogeneity in the ultrasound definitions for the principal lesions of enthesitis in the published literature and second, to evaluate the metric properties of ultrasound for detecting enthesitis according to the OMERACT filter.

Methods

Search was performed in PUBMED and EMBASE. Both grey-scale and Doppler definitions of enthesitis, including describing features of enthesitis, were collected and metrological qualities of studies were assessed.

Results

After selection, 48 articles were analyzed. The definition of ultrasound enthesitis and elementary features varied among authors. Grey-scale enthesitis was characterized by increasing thickness (94% of studies), hypoechogenicity (83%), enthesophytes (69%), erosions (67%), calcifications (52%), associated bursitis (46%) and cortical irregularities (29%). Only 46% of studies reported the use of Doppler. High discrepancies were observed on frequency, type of probe and Doppler mode used. Face and content validity were the most frequently evaluated criteria (43%) followed by reliability (29%) and responsiveness (19%).

Conclusions

Ultrasound has evidence to support face, content validity and reliability for the evaluation of enthesitis, though there is a lack of well-reported methodology in most of the studies. Consensus on elementary lesions and standardization of exam is needed to determine the ultrasound definition of enthesitis in grey-scale and in Doppler for future applications.

Ultrasound revealing subclinical enthesopathy at the greater trochanter level in patients with spondyloarthritis

This study was conducted to determine the prevalence of subclinical entheseal involvement at the greater trochanter level by ultrasound in patients with spondyloarthritis. Forty-six patients with spondyloarthritis and 46 healthy age- and sex-matched controls were studied. All patients with no clinical evidence of enthesopathy at the greater trochanter underwent an ultrasound examination. The following three entheses were scanned bilaterally: anterior insertion of gluteus minimus, anterior insertion of gluteus medius, and posterior insertion of gluteus medius. Ultrasound findings of enthesopathy were thickening, calcifications, bone erosions, enthesophytes, bursitis, and power Doppler signal. A total of 276 entheses were evaluated in spondyloarthritis patients. In 112 out of 276 (40.5%), grayscale ultrasound found enthesopathy. The enthesis with the highest number of signs of enthesopathy was the anterior insertion of gluteus medius (46/276) (16%), followed by posterior insertion of gluteus medius (37/276) (13.4%) and anterior insertion of gluteus minimus (29/276) (10.5%). In the healthy population, ultrasound found entesopathy in 80 out of 276 (29%) entheseal sites (p < 0.0001). Posterior insertion of gluteus medius enthesis was the more frequently involved (34/276) (12.3%), followed by anterior insertion of gluteus medius (24/276) (8.6%) and anterior insertion of gluteus minimus (22/276) (7.9%). Power Doppler was found more frequently in patients with spondyloarthritis compared with healthy controls (1% vs 0%). Our results show a higher prevalence of subclinical enthesopathy at the greater trochanter level in patients with spondyloarthritis than in age- and sex-matched healthy controls.

Teaching enthesis ultrasound: experience of an ultrasound training workshop

To evaluate a standardised enthesis ultrasound training method, a workshop was conducted to train rheumatologists on enthesis ultrasound. After a theoretical session about ultrasound elementary enthesis lesions (changes in tendon architecture/thickness, bone proliferation/erosion, bursitis or Doppler signal), a reading exercise of 28 entheses' ultrasonographic images (plantar fasciae, Achilles, origin and insertion of patellar tendon) was completed. Participants scored through an electronic multiple-choice device with six possible lesions in each enthesis. To assess the adequacy and efficacy of the workshop, we explored the following: (1) subjective outcomes: a 12-item structured satisfaction questionnaire (graded 1-5 using Likert scale) and (2) objective outcomes of reliability: sensitivity (Se), specificity (Sp) and percentage of correctly classified cases (CC). Forty-nine participants attended the workshop. The satisfaction questionnaire demonstrated a 4.7 mean global value. The inter-reader Kappa reliability coefficient was moderate for the plantar fascia (0.47), Achilles tendon (0.47), and distal patellar tendons (0.50) and good for the proximal patellar tendon (0.63). The whole group means comparing to teachers' consensus were as follows: (a) plantar fascia: Se, 73.2%; Sp, 87.7%; CC, 83.3%; (b) Achilles: Se, 66.9%; Sp, 85.0%; CC, 79.5%; (c) distal patellar tendon: Se, 74.6%; Sp, 85.3%; CC, 82.1%; and (d) proximal patellar tendon: Se, 82.2%; Sp, 90.6%; CC, 88%. The proposed learning method seemed to be simple, easily performed, effective and well accepted by the target audience.

The OMERACT Ultrasound Task Force — Status and Perspectives

This article reports the most recent work of the Outcome Measures in Rheumatology (OMERACT) Ultrasound Task Force, and highlights the future research priorities discussed at the OMERACT 10 meeting. Results of the following studies were presented: (1) intra- and interobserver reliability of ultrasound detecting and scoring synovitis in different joints of patients with rheumatoid arthritis (RA); (2) systematic review of previous ultrasound scoring systems of synovitis in RA; (3) enthesitis systematic review and Delphi definition exercise in spondyloarthritis enthesitis; (4) enthesitis intra- and interobserver reliability exercise; and (5) Delphi definition exercise in hand osteoarthritis, and reliability exercises. Study conclusions were discussed, and a future research agenda was approved, notably further validation of an OMERACT ultrasound global synovitis score (GLOSS) in RA, emphasizing the importance of testing feasibility, predictive value, and added value over standard clinical variables. Future research areas will include validating scoring systems for enthesitis and osteoarthritis, and testing the metric qualities of ultrasound for evaluating tenosynovitis and structural damage in RA.

Clinical and ultrasonography assessment of peripheral enthesitis in ankylosing spondylitis

OBJECTIVE

The aim of this study was to compare clinical examination with power Doppler US (PDUS) in the detection of entheseal abnormalities in patients with AS.

METHODS

Thirty-six AS patients underwent clinical and PDUS examination of the following bilateral entheseal sites: common extensor tendon at its insertion at the lateral humeral epicondyle; gluteus tendons at their insertion at the greater trochanter; quadriceps tendon at its insertion at the superior pole of the patella; patellar tendon at its proximal insertion at the inferior pole of the patella; patellar tendon at its distal insertion at the tibial tuberosity; Achilles tendon at its insertion at the calcaneus; and plantar aponeuroses at its insertion at the calcaneus.

RESULTS

Clinical and PDUS examination revealed at least one abnormal enthesis in 23 (63.9%) and 35 (97.2%) AS patients, respectively. Furthermore, of 432 entheses examined in our 36 AS patients, 64 (14.8%) were considered abnormal by clinical examination and 192 (44.4%) by PDUS. US abnormalities most commonly found were enthesophytes (31.7%), calcifications (33.7%), thickening (29.8%) and hypoechogenicity (26.6%). We found erosions and PD signals in 9.7 and 6% of examined entheseal sites, respectively. The evidence of entheseal abnormalities by clinical examination has a poor likelihood ratio (LR) for the presence of US abnormalities with vascularization (LR = 1.61), without vascularization (LR = 1.24) or erosions (LR = 1.51) at all sites.

CONCLUSIONS

PDUS permits detection of structural and inflammatory abnormalities of the enthesis in AS and may complement the physical examination in order to better evaluate enthesitis.