A sonographic enthesitic index of lower limbs is a valuable tool in the assessment of ankylosing spondylitis

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.

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.

Ultrasound features of shoulder involvement in patients with ankylosing spondylitis: a case-control study

Background

During Ankylosing spondylitis (AS) courses, shoulder involvement is common. However, etiologies of shoulder pain in patients with AS remain to be defined. The aim of this study was to investigate the prevalence of ultrasound (US) abnormalities in shoulders of patients with ankylosing spondylitis (AS), and to determine predictive factors of ultrasound shoulder enthesitis.

Methods

38 patients with AS were included with 38 age and sex-matched healthy controls. All patients fulfilled the modified New York criteria for ankylosing spondylitis. Clinical and demographical data were recorded. US examination of bilateral shoulders was performed by a musculoskeletal sonographer according to a defined protocol that included imaging of the insertions of supraspinatus, subscapularis and infraspinatus tendons, rotator cuff tendons, subacromial-subdeltoid bursa, acromioclavicular joint, and glenohumeral joint.

Results

The mean age of patients and controls was 36 years, each group of patients and controls comprised 22 men (57.9%) and 16 women (42.1%). Disease duration was 9.6 ± 7.2 years. Among 38 patients with AS, 21 had coxitis (55%) and 19 had previous or current shoulder pain (50%). AS shoulders presented significantly more ultrasound enthesitis than controls shoulders (43 shoulders (56.6%) versus 8 shoulders (10.5%) respectively). Involvement of rotator cuff tendons was significantly higher in patients with AS compared with control subjects (16/38 (42.1%) versus 6 (15.2%) respectively). However, involvement of gleno-humeral and acromio-clavicular joints was infrequent in both groups. In patients with AS, we found that the presence of coxitis was the only significant predictive factors of shoulder enthesitis (Odds Ratio (OR) = 9.4; Confidence interval (CI) 95% (1.10; 81.9), p = 0.04).

Conclusions

Ultrasound abnormalities of shoulders are common in patients with AS, and the most frequent abnormalitie was enthesitis, which was associated with the presence of coxitis.

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.

Spondyloarthritis Research Consortium of Canada (SPARCC) enthesitis index in Turkish patients with ankylosing spondylitis: relationship with disease activity and quality of life

AIM

The aim of this study was to investigate the relationship between Spondyloarthritis Research Consortium of Canada (SPARCC) enthesitis index and disease activity and health-related quality of life in patients with ankylosing spondylitis (AS).

METHODS

Eighty-six AS patients not receiving antitumour necrosis factor (TNF) therapy were included in the study. Spinal pain by visual analogue scale (pain VAS rest and activity), disease activity by Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), functional capacity by Bath Ankylosing Spondylitis Functional Index (BASFI), enthesitis severity by SPARCC index, quality of life by Short Form-36 (SF-36), and Bath Ankylosing Spondylitis Metrology Index (BASMI) were assessed in patients. In the laboratory evaluations, the erythrocyte sedimentation rates and serum C-reactive protein levels of the patients were determined.

RESULTS

All participants were aged between 18 and 65 years, with a mean age of 36.9 ± 11.13 years. The most frequent region of enthesitis was Achilles tendon insertion into calcaneum (55.8%). Pain VAS rest and activity, BASFI and all parameters of SF-36 were significantly different in AS patients with and without enthesitis. SPARCC index was significantly correlated with pain VAS activity (P < 0.05), pain VAS rest, BASDAI, BASFI and all parameters of SF-36 (P < 0.001). There were no correlations between SPARCC index and BASMI, disease duration and laboratory parameters (P > 0.05).

CONCLUSION

The clinical assessment of enthesitis in AS is an important outcome measure, and enthesitis indexes such as SPARCC enthesitis index can be valuable tools in the evaluation of disease activity in AS patients not receiving anti-TNF therapy.

Value of ultrasound in rheumatologic diseases

The use of musculoskeletal ultrasound in rheumatology clinical practice has rapidly increased over the past decade. Ultrasound has enabled rheumatologists to diagnose, prognosticate and monitor disease outcome. Although international standardization remains a concern still, the use of ultrasound in rheumatology is expected to grow further as costs fall and the opportunity to train in the technique improves. We present a review of value of ultrasound, focusing on major applications of ultrasound in rheumatologic diseases.

The evolution of ultrasound in rheumatology

Musculoskeletal ultrasound is a powerful tool not only for evaluating joint and related structures but also for assessing disease activity. Ultrasound in rheumatology has rapidly evolved and been incorporated into routine clinical practice over the past decade. Moreover, technological development of equipment has made it more accessible for rheumatologists. We present a review of advances in ultrasound in rheumatology, focusing on major chronological developments.

The use of ultrasound for the assessment of enthesitis in patients with spondyloarthritis

Seronegative spondyloarthritis (SpA) represents a group of diseases that share certain genetic, clinical, and radiographic features. Enthesitis, inflammation at the site of tendon insertion into the bone, involving both the axial and the peripheral joints, is an important sign of SpA. Clinical diagnosis of enthesitis, however, is neither sensitive nor specific; thus, the diagnosis of enthesitis often relies on typical abnormalities in imaging studies. Due to its low costs and availability, ultrasound is emerging as the preferred technique for detection of enthesitis for both clinical and research purposes. Ultrasonographic features of enthesitis include tendon hypoechogenicity and thickening, calcifications, bone erosions, and Doppler signal. Several semi-quantitative scoring systems have been developed to quantify ultrasonographic abnormalities of the entheses. These methods have been used for early diagnosis and classification of SpA as well as for monitoring response to treatment.

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.

[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.

The Ultrasound Imaging Module: A Report from the GRAPPA 2010 Annual Meeting

In a plenary session at the 2010 meeting of the Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA), the use of sonography for evaluating articular disease and enthesitis in psoriasis and psoriatic arthritis (PsA) was reviewed. Ultrasound can readily demonstrate signs of synovitis, erosions, and osteoproliferation. There is a need to develop ultrasound joint indices to evaluate and follow PsA longitudinally. Sonography is able to depict ultrastructural features of enthesitis, as well as increased vascularity. Sonographic signs of subclinical enthesitis in patients with psoriasis have been reported by 2 groups, 1 of which has reported limited longitudinal data that suggest baseline composite enthesitis scores may predict future risk of PsA. Although recent studies have studied mostly lower extremity entheses, further work is needed to clarify if other areas need to be included, especially within the framework of the synovial entheseal complex. The study design of the PREPARE (Prevalence of Psoriatic Arthritis in Adults with Psoriasis) trial was also presented.

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.

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.

High prevalence of ultrasonographic synovitis and enthesopathy in patients with psoriasis without psoriatic arthritis: a prospective case-control study

OBJECTIVE

To investigate the presence of synovitis, tenosynovitis and enthesitis with power Doppler (PD) ultrasonography (US) in patients with psoriasis without musculoskeletal diseases as compared with controls with other skin diseases without musculoskeletal disorders.

METHODS

A total of 162 patients with plaque psoriasis and 60 age-matched controls with other skin diseases, all without musculoskeletal diseases, were prospectively recruited at 14 centres. They underwent dermatological and rheumatological assessment and a blinded PDUS evaluation. Clinical assessment included demographics, comorbidities, severity of psoriasis, work and sport activities and musculoskeletal clinical examination. PDUS evaluation consisted of the detection of grey scale (GS) synovitis and synovial PD signal in 36 joints, GS tenosynovitis and tenosynovial PD signal at 22 sites, and GS enthesopathy and entheseal PD signal in 18 entheses.

RESULTS

US synovitis and enthesopathy were significantly more frequent in psoriatic patients than in controls (P = 0.024 and 0.005, respectively). The percentage of joints with US synovitis was 3.2% in the psoriasis group and 1.3% in the control group (P < 0.0005). US enthesopathy was present in 11.6% of entheses in the psoriasis group and 5.3% of entheses in the control group (P < 0.0005). Entheseal PD signal was found in 10 (7.4%) psoriatic patients, whereas no controls showed this finding (P = 0.05). Among demographic and clinical data, having psoriasis was the only significant predictive variable of the presence of US synovitis [odds ratio (OR) 2.1; P = 0.007] and enthesopathy (OR 2.6; P = 0.027).

CONCLUSION

Psoriatic patients showed a significant prevalence of asymptomatic US synovitis and enthesopathy, which may indicate a subclinical musculoskeletal involvement.

Power Doppler Ultrasonography Assessment of Entheses in Spondyloarthropathies: Response to Therapy of Entheseal Abnormalities

Objective.

To investigate the response to therapy of entheseal abnormalities assessed with power Doppler (PD) ultrasound (US) in spondyloarthropathies (SpA).

Methods.

A total of 327 patients with active SpA who were starting anti-tumor necrosis factor (TNF) therapy were prospectively recruited at 35 Spanish centers. A PDUS examination of 14 peripheral entheses was performed by the same investigator in each center at baseline and at 6 months. The following elementary lesions were assessed at each enthesis (presence/absence): morphologic abnormalities (hypoechogenicity and/or thickening), entheseal calcific deposits, cortical abnormalities (bone erosion and/or proliferation), adjacent bursitis and intraenthesis and perienthesis (tendon body and/or bursa) PD signal. Response to therapy of each elementary lesion was assessed by calculating change in the cumulative presence from baseline to 6 months. Intraobserver reliability of PDUS was evaluated by blindly assessing the stored baseline images 3 months after the real-time examination.

Results.

Complete data were obtained on 197 patients who received anti-TNF therapy for 6 months. In 91.4% of the patients there were gray-scale or PD elementary lesions at baseline and at 6 months. Cumulative entheseal morphologic abnormalities, intraenthesis PD, perienthesis PD, and bursitis showed a significant decrease from baseline to 6 months (p < 0.05). There was high intraobserver reliability for all elementary lesions (interclass correlation coefficient > 0.90, p < 0.0005).

Conclusion.

Entheseal morphologic abnormalities, PD signal, and bursitis were US abnormalities that were responsive to anti-TNF therapy in SpA. PDUS can be a reproducible method for multicenter monitoring of therapeutic response in enthesitis of SpA.

Subclinical entheseal involvement in patients with psoriasis: an ultrasound study

OBJECTIVES

The main aim of the present study was to determine the prevalence of subclinical entheseal involvement at lower limbs by ultrasound (US) in patients with psoriasis. The secondary aim was to determine the interobserver reliability of the Glasgow Ultrasound Enthesitis Scoring System (GUESS) and power Doppler (PD) technique in the assessment of enthesopathy.

METHODS

The study was conducted on 45 patients with psoriasis and 45 healthy sex- and age-matched controls. All patients with no clinical evidence of arthritis or enthesitis underwent an US examination. All US findings were identified according to GUESS. The interobserver reliability was calculated in 15 patients with psoriasis.

RESULTS

A total of 450 entheses in 45 patients with psoriasis were evaluated by US. In 148 of 450 (32.9%) entheses, grayscale US found signs indicative of enthesopathy. In 4/450 (0.9%) entheses PD signal was detected. In the healthy population, US found signs of enthesopathy in 38 of 450 (8.4%) entheses and no PD signal was detected. The GUESS score was significantly higher in patients with psoriasis than in healthy controls (P < 0.0001). Both concordance correlation coefficient and unweighted κ values for US findings showed an excellent agreement (0.906 and 0.890, respectively).

CONCLUSIONS

Our results indicate that both grayscale US and PD findings indicative of enthesopathy were more frequent in patients with psoriasis. The US ability to detect signs of subclinical enthesopathy should be the object of longitudinal investigations to define its value in predicting the clinical onset of psoriatic arthritis.

Assessment of Achilles enthesitis in the spondyloarthropathies by colour Doppler energy ultrasound in the context of the 'enthesis organ'

OBJECTIVES

To identify the characteristic features of Achilles enthesitis of the spondyloarthropathies (SpA) detectable by colour Doppler energy ultrasound (CDEU) in the context of the 'enthesis organ'.

METHODS

Seventy patients with SpA and 15 healthy subjects were clinically evaluated and underwent CDEU examination of the Achilles entheses. The CDEU images were evaluated according to five distinctive CDEU features of enthesitis in the context of the enthesis organ.

RESULTS

Fifty-six of the 70 SpA patients (80%) showed at least one abnormal finding of the enthesitis on CDEU examination, affecting 91 of 140 Achilles entheses examined (65%). Only 22 of 140 Achilles entheses (15.7%) showed abnormal vascularization in the peri-sesamoidal and periosteal areas or in the area of enthesis fibrocartilage. In addition, 67 (47.9%) and 18 (12.9%) of 140 Achilles entheses examined showed cortical bone irregularities and erosions, respectively, at areas of the periosteal and the enthesis fibrocartilage. Sixteen (88.9%) of 18 clinically detected Achilles enthesitis and six (75%) of eight Achilles entheses with swelling on clinical examination presented corresponding abnormalities on CDEU examination. The Doppler twinkling artefact (TA) was observed consistently in all normal entheses and completely disappeared upon stabilization of the probe application. The C-reactive protein (CRP) level was higher in the patients with cortical bone erosion than in those without erosion.

CONCLUSIONS

This study demonstrates the characteristic features of enthesitis detectable by CDEU in the context of the enthesis organ and shows a good correlation with clinical as well as with laboratory findings.

[Cross-sectional imaging of peripheral involvement in ankylosing spondylitis]

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.

[Ultrasound scores in spondyloarthritis]

Ultrasound is proving its validity in the assessment of patients with spondyloarthritis. This paper reviews the various indices validated for the quantification of the activity or for the diagnosis of involvement of peripheral joints, enthesis and sacroiliac joints of these patients. The studies are still preliminary but point to future uses of ultrasound in spondyloarthritis.

Relationship between enthesitis, clinical parameters and quality of life in spondyloarthritis

OBJECTIVE

To investigate the involvement of enthesis and its correlation with clinical and quality of life parameters in patients with spondyloarthritis (SpA).

METHODS

One hundred and eighteen patients who comply with the SpA classification criteria of the European Spondylarthropathy Study Group (ESSG) were included into the study. Clinical parameters such as morning stiffness, rest pain, activity pain, tender joints and swollen joints were evaluated. Enthesitis were assessed by Mander Enthesis Index (MEI). The quality of life was assessed by Short Form-36 (SF-36).

RESULTS

The incidence of enthesitis in patient with SpA was found at a rate of 84.9%. There was a significant correlation between MEI and morning stiffness, disease duration, tender joints and six subgroups of SF-36. The highest correlation was found between MEI and number of tender joint (p<0.001).

CONCLUSION

Enthesitis is commonly seen among patients with SpA. Enthesitis also affects the life quality of patients negatively.

Imaging of the sacroiliac joint involvement in seronegative spondylarthropathies

Involvement of the sacroiliac joints is the first predominant finding of all seronegative spondylarthropathies (SpA) subsets, such as ankylosing spondylitis, psoriatic arthritis, and undifferentiated SpA. Although conventional radiography is indicated in the initial evaluation of sacroiliac joints diseases, it is often insensitive for demonstrating the early changes of sacroiliitis, so other imaging techniques typically are often necessary to clarify the pathology and for establishing the early diagnosis of seronegative SpA. Other imaging modalities, including computed tomography (CT), magnetic resonance imaging (MRI), ultrasonography (US), and bone scintigraphy have improved visualization of inflammatory changes at the sacroiliac joints (SIJ). CT scans are indicated for disease processes in which bony destruction or ossification may occur. MRI has been proposed as an imaging method to detect sacroiliitis earlier. MRI can identify both inflammation and structural changes caused by inflammation, while radiographs show only structural changes. MRI may be particularly useful in making a diagnosis of SpA. Musculoskeletal US has an increasing and relevant role in the evaluation of SpA mainly for its ability to assess joint and periarticular soft tissue involvement and in particular for its capacity to detect enthesitis. US assessment in general is safe, noninvasive, and comparably cheap, showing itself as a complimentary tool to clinical evaluation in SpA; nevertheless, it is very user dependent. Bone scintigraphy is at most of limited diagnostic value for the diagnosis of established AS, including the early diagnosis of probable/suspected sacroiliitis. The main aim of this study is to introduce the clinical and radiological aspects of the SIJ involvement in SpA, particularly the contribution of the different imaging techniques.

Progress in spondylarthritis. Spondyloarthritis: lessons from imaging

The advent of magnetic resonance imaging (MRI) and advanced sonographic techniques has led to a resurgence of interest in the role of imaging in the evaluation and management of spondyloarthritis. Radiography remains the cornerstone of diagnosis although MRI is more sensitive in early stages of the disease. Inflammatory changes in the sacroiliac joints and spine can now be reliably quantified and can also predict the subsequent development of radiographic changes in the corresponding locations. MRI-based scoring systems for inflammation are highly responsive, facilitating proof-of-concept studies of new therapies for spondyloarthritis. Assessment of chronic changes is much less reliable using MRI, while assessment using radiography lacks sensitivity to change. Assessment of disease modification therefore remains a principle challenge in the development of new therapies for ankylosing spondylitis. Ultrasound may be the preferred approach to the assessment of peripheral inflammation, especially enthesitis. Scintigraphy and computed tomography offer few advantages over MRI.

Imaging of seronegative spondyloarthritis

Magnetic resonance imaging (MRI) and ultrasonography (US) are useful adjuncts in the diagnosis of seronegative spondyloarthritides (SpA); a group of diseases that present early at a stage when radiographic assessment is invariably normal. This chapter will review how MRI and US can be used in the evaluation of early SpA. The diffuse osteitis/enthesitis on MRI may serve as a diagnostic hallmark for SpA spinal disease, but needs confirmatory studies for comparison with other spinal pathologies. MRI is the modality of choice for monitoring axial disease in anti-tumour necrosis factor (TNF) therapy responses in the research environment, but it is not yet certain whether this will be relevant in clinical practice. Anti-TNF therapy may be associated with regression of MRI-determined osteitis, but retardation of associated bony fusion is debatable. MRI and US are still undergoing evaluation for the diagnosis of enthesitis of the appendicular skeleton; US, in particular, shows promise at these sites.