Power Doppler ultrasonography of painful Achilles tendons and entheses in patients with and without spondyloarthropathy—a comparison with clinical examination and contrast-enhanced MRI

Subclinical enthesitis in enthesitis-related arthritis and sacroiliitis associated with familial Mediterranean fever

OBJECTIVES

In our study, we investigated the presence of subclinical enthesitis by ultrasonography (US) in asymptomatic patients with enthesitis-related arthritis (ERA) and sacroiliitis associated with familial Mediterranean fever (FMF).

METHODS

A total of 50 patients, including 35 patients with ERA and 15 with sacroiliitis associated with FMF, were included in the study. All patients were evaluated with US by a paediatric radiologist. Enthesis of seven tendons (common extensor and flexor tendons, quadriceps tendon, proximal and distal patellar tendon, Achilles tendon, and plantar fascia) was examined on both sides.

RESULTS

Subclinical enthesitis was detected in 10 ERA (28.5%) and three FMF (20%) patients. Enthesitis was radiologically diagnosed in 16 (2.3%) out of 700 evaluated entheseal sites. The most frequent sites of enthesitis were Achilles (37.5%) and quadriceps (31.3%) tendons. All patients were in clinical remission and had no active complaints, and acute phase reactants were within normal limits. Therefore, the patients were followed up without treatment change. However, disease flare-up was observed in three of these patients (23.1%) during the follow-up, and their treatments were intensified.

CONCLUSIONS

Our results showed that the US can be particularly helpful in detecting subclinical enthesitis and predicting disease flare-ups.

Ultrasonography of heel entheses in axial spondyloarthritis patients: frequency and assessment of associated factors

PURPOSE

Foot entheses involvement is a common manifestation of spondyloarthritis. The superiority of ultrasonography examination in foot entheses damages detection has been reported. We aimed to compare the ultrasonography findings of foot entheses between spondyloarthritis patients. and healthy controls and to identify factors associated with enthesitic heel involvement.

METHODS

We conducted a cross-sectional study including 37 patients with axial spondyloarthritis (G1) and 37 healthy subjects matched by age and gender (G0). The following pro-inflammatory cytokines were measured: Interleukin (IL-)1, IL-6, IL-17, and IL-23. A blind ultrasonography of foot entheses was performed to examine calcaneal tendon (CT) and plantar fascia (PF).

RESULTS

The mean age was 44.62 ± 12.31 years. Non-steroidal anti-inflammatory drugs were taken in 92% of patients. Clinical heel enthesopathy was noted in 10 patients (27%) of G1. No participant has enthesitic pain in G0. Ultrasonography changes in CT and PF were more frequent in G1 than G0 (p = 0.001 and p = 10-3, respectively). In the PF, tendon thickening was significantly higher in G1 than G0 (p = 0.03). Power Doppler in both enthesitic sites was exclusively observed in G1 (p = 10-3). Regarding associated factors, CT enthesophytes were less frequent in patients taking non-steroidal anti-inflammatory drugs continuously or having regular physical activity. PF structural damages were associated with higher erythrocyte sedimentation rate (p = 0.02), higher IL-23 level (p = 0.01), and higher disease activity (p = 0.04).

CONCLUSION

Ultrasonography lesions of heel entheses were frequent in spondyloarthritis. Disease activity and inflammatory markers were higher in patients with heel enthesitis. Non-steroidal anti-inflammatory drugs intake and regular physical activity may prevent enthesophytes' occurrence.

Enthesitis-related arthritis: the clinical characteristics and factors related to MRI remission of sacroiliitis

Background

To describe the clinical characteristics and explore the factors related to the MRI remission of sacroiliitis in patients with enthesitis-related arthritis (ERA).

Methods

Patients with ERA from 2018–2022 in our medical center were retrospectively reviewed, which identified according to Pediatric Rheumatology International Trials Organization (PRINTO) criteria. Demographics, clinical characteristics, examinations, and treatments were described. Univariate and multivariate logistic regression models were used to analyze the factors related to MRI remission of sacroiliitis in ERA.

Results

This retrospective study included 160 ERA patients (51.9% male) with a mean onset age of 9.2 ± 3.0 years. There were 144 cases (81.9%) with peripheral arthritis, and the hip, knee, and ankle joints were the most commonly involved joints. Enthesitis occurred in 48 cases (30.0%), and sacroiliitis occurred in 142 cases (88.5%) at diagnosis. Human leukocyte antigen (HLA)-B27 was positive in 33 cases (17.1%), and acute uveitis occurred in 3 cases (1.9%). The majority of patients (93.7%) were treated with disease-modifying anti-rheumatic drugs (DMARDs), and 60% with biologics. Among 62 patients with MRI-defined sacroiliitis, 27 (43.5%) cases showed improvement in the sacroiliac joint lesion after treatment. Multivariate logistic regression analysis showed that duration from onset to diagnosis of less than 3 months (OR = 3.609, 95% CI: 1.068–12.192) and active joints of more than 4 (OR = 4.916, 95% CI: 1.006–24.037) were independent factors.

Conclusion

We highlighted differences in ERA clinical characteristics. Patients with a shorter diagnosis time and more joint involvement improved more significantly in sacroiliac joint lesions after treatment.

A clinical practice guideline for the screening and assessment of enthesitis in patients with spondyloarthritis

OBJECTIVE

The aim of this review is to provide guidance on the selection of approaches to the screening and assessment of enthesitis in patients with spondyloarthritis (SpA).

METHODS

Twenty-four questions regarding the approaches to the screening and assessment of enthesitis and the implementation details were devised, followed by a systemic literature review. The Grading of Recommendations Assessment, Development, and Evaluation methodology was employed in the development of this guideline, with modifications to evaluate non-interventional approaches under comprehensive consideration of costs, accessibility, and evidence strength. A consensus from the voting panel was required for the inclusion of the final recommendations and the strength of each recommendation.

RESULTS

Seventeen recommendations (including five strong recommendations) were included in this guideline. The voting panel expressed unequivocal support for the necessity of screening and assessment of enthesitis in patients with SpA. It was agreed unanimously that symptom evaluation and physical examination should serve as the initial steps to the recognition of enthesitis, whereas Maastricht Ankylosing Spondylitis Enthesitis Score is a reliable tool in both clinical trials and daily medical practice. Ultrasound examination is another reliable tool, with power Doppler ultrasound as an informative addition. Notwithstanding its high resolution, MRI is limited by the costs and relatively low accessibility, whereas radiographs had low sensitivity and therefore should be rendered obsolete in the assessment of enthesitis. PET/CT was strongly opposed in the detection of enthesitis.

CONCLUSION

This guideline provides clinicians with information regarding the screening and assessment of enthesitis in patients with SpA. However, this guideline does not intend on dictating choices, and the ultimate decisions should be made in light of the actual circumstances of the facilities.

Diffuse Peripheral Enthesitis in Metabolic Syndrome: A Retrospective Clinical and Power Doppler Ultrasound Study

OBJECTIVES

To investigate peripheral enthesitis with power Doppler ultrasound (PDUS) in patients presenting low back pain (LBP) and metabolic syndrome (MetS) in comparison with patients with only LBP, to correlate US scores with clinical-anthropometric characteristics, and to define any relationship between enthesitis and concurrent diffuse idiopathic hyperostosis syndrome (DISH).

METHODS

Sixty outpatients with LBP and MetS, evaluated with multi-site entheseal PDUS, scoring inflammatory and structural damage changes, were retrospectively analyzed. A group of 60 subjects with LBP, without MetS and evaluated with the same protocol, was analyzed as the control group.

RESULTS

Patients showed overweight (BMI 29.8) and low-grade inflammatory state (C-reactive protein [CRP] 0.58mg/dL, erythrosedimentation rate [ESR] 20.2mm/h). Enthesitis was demonstrated in 52 (86%) patients (17.6% entheses), and in 8 controls (13.3%) (p<.00001). PD signals (15% of patients) were associated with entheseal pain (p=.0138). US scores correlated with body mass index (BMI), pain, type 2 diabetes. In 28 (46%) patients a concurrent DISH was diagnosed, correlating with older age (p<.0001), CRP (p=.0428), ESR (p=.0069) and PDUS scores (p=.0312 inflammatory, p=.0071 structural). MetS had a strong association (OR 4.375, p=.0007) with concurrent DISH.

CONCLUSIONS

Diffuse peripheral enthesitis is very common in MetS. Almost half of MetS patients can have a concurrent diagnosis of DISH; they are older, with higher inflammation, and higher PDUS enthesitis scores.

The EFSUMB Guidelines and Recommendations for Musculoskeletal Ultrasound - Part I: Extraarticular Pathologies

The first part of the guidelines and recommendations for musculoskeletal ultrasound, produced under the auspices of the European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB), provides information about the use of musculoskeletal ultrasound for assessing extraarticular structures (muscles, tendons, entheses, ligaments, bones, bursae, fasciae, nerves, skin, subcutaneous tissues, and nails) and their pathologies. Clinical applications, practical points, limitations, and artifacts are described and discussed for every structure. After an extensive literature review, the recommendations have been developed according to the Oxford Centre for Evidence-based Medicine and GRADE criteria and the consensus level was established through a Delphi process. The document is intended to guide clinical users in their daily practice.

Musculoskeletal pain in psoriasis - relation to inflammation and additional value of ultrasound in psoriatic arthritis classification

OBJECTIVE

To investigate and compare clinical features and ultrasound signs of inflammation in joints and entheses in patients with psoriasis (PsO) with and without musculoskeletal pain, and the additional value of ultrasound in classification of psoriatic arthritis (PsA). Furthermore, to explore the association between such findings and patient-reported outcomes (PROs) and the performance of screening-questionnaires for identifying patients with PsA.

METHODS

Patients with PsO (n = 126) recruited from a nationwide survey were evaluated at one of four rheumatology departments. The evaluation included clinical examination, laboratory tests, radiography, greyscale (GS) and colour Doppler (CD) ultrasound of 48 joints and 12 entheses, PROs, and four screening-questionnaires for PsA. Patients were classified with Classification for PsA (CASPAR), ultrasound-modified CASPAR, and ultrasound-only criteria.

RESULTS

When subgroups of self-reported pain (63%), no pain (29%) and diagnosed PsA (9%) were compared, patients with pain had higher tenderness-related clinical scores (tender joints, entheses and fibromyalgia points) and ultrasound GS sum-scores, compared with 'no pain' patients. PROs were negligibly-moderately correlated with pain-related clinical scores (Spearman's rho = 0.11-0.59, all patients), and negligibly-weakly with ultrasound sum-scores (rho = 0.01-0.34). More patients could be classified as PsA when ultrasound synovitis/enthesitis was included as entry criterion (ultrasound-modified CASPAR, 66% of all patients) compared with conventional CASPAR (35%) or ultrasound-only criteria (52%). Sensitivities of screening-questionnaires were low for fulfilment of CASPAR (0.23-0.66), ultrasound-modified CASPAR (0.17-0.57), and ultrasound-only (0.20-0.57) criteria.

CONCLUSION

Self-reported pain in PsO is related to ultrasound inflammation. Ultrasound-modified CASPAR criteria identified almost twice as many patients as conventional CASPAR criteria. Screening-questionnaires showed limited value.

Explaining Variability in the Prevalence of Achilles Tendon Abnormalities: A Systematic Review With Meta-analysis of Imaging Studies in Asymptomatic Individuals

OBJECTIVE

To estimate the prevalence of, and factors associated with, Achilles tendon abnormalities observed on imaging in asymptomatic individuals.

DESIGN

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

LITERATURE SEARCH

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

STUDY SELECTION CRITERIA

We included studies that reported the prevalence of Achilles tendon abnormalities, observed with any imaging modality, in an asymptomatic population. We excluded studies if participant mean age was younger than 12 years or if participants had current/previous lower-limb tendon injuries/symptoms or other systemic conditions.

DATA SYNTHESIS

Random-effects proportion meta-analysis was used to estimate prevalence. We used meta-regression for continuous variables (mean age and body mass index [BMI], sample size, proportion of female participants) and stratified categorical variables (imaging modality and participation in physical activity) to explain between-study heterogeneity.

RESULTS

We included 91 studies (10 156 limbs, 5841 participants). The prevalence of Achilles tendon abnormalities on imaging ranged from 0% to 80% per participant. Between-study heterogeneity was high (I²>90%, P<.001), precluding data pooling. Between-study heterogeneity was partly explained by participant mean BMI (slope, 2.8% per 1-unit increase in BMI; 95% confidence interval: 0.57%, 5.03%; P = .015) and participation in physical activity per limb, and mean age of 40 years old or older (P = .022) per participant.

CONCLUSION

There was substantial variability in the prevalence of Achilles tendon abnormalities on imaging in asymptomatic individuals. Higher prevalence of abnormalities was associated with older age (40 years old or older), higher BMI, and participation in physical activity. A large proportion of heterogeneity remains unaccounted for, likely due to variations in abnormality definitions and study design. J Orthop Sports Phys Ther 2021;51(5):232-252. Epub 28 Mar 2021. doi:10.2519/jospt.2021.9970.

Ultrasound, magnetic resonance imaging and radiography of the finger joints in psoriatic arthritis patients

OBJECTIVE

To report the discrepancies and agreements between ultrasound (US), magnetic resonance imaging (MRI) and radiography of the hand in psoriatic arthritis (PsA), and to compare the sensitivity and specificity of US and radiography to MRI as the gold standard imaging study in PsA.

METHODS

All of the 100 prospectively recruited consecutive PsA patients underwent clinical assessment and concomitant radiographic, US and MRI studies of the metacarpophalangeal, proximal interphalangeal and distal interphalangeal joints of one hand. Synovitis, flexor tenosynovitis, extensor paratenonitis, erosions and bone proliferations were identified and scored. All readers were blinded to clinical data, and agreement was calculated based on prevalence-adjusted bias-adjusted kappa (PABAK).

RESULTS

The prevalence of synovitis, flexor tenosynovitis, extensor paratenonitis and erosions was similar for US and MRI, while that of bone proliferation was significantly increased in US and radiography compared to MRI (P < 0.001). The absolute agreement between US and MRI was good-to-very good for synovitis (85%-96%, PABAK=0.70-0.92), flexor tenosynovitis (93%-98%, PABAK=0.87-0.96), and extensor paratenonitis (95%-98%, PABAK=0.90-0.97). Agreement between US, MRI and radiography was 96%-98% (PABAK=0.92-0.97) for erosions and 71%-93% (PABAK=0.47-0.87) for bone proliferations. Sensitivity of US with MRI as gold standard was higher for synovitis (0.5-0.86) and extensor paratenonitis (0.63-0.85) than for flexor tenosynovitis (0.1-0.75), while the specificity was high for each pathology (0.89-0.98).

CONCLUSION

There is very good agreement between US and MRI for the detection of inflammatory changes in finger joints in PsA. US, radiography and MRI have a good-to-very good agreement for destructive changes.

Diffuse Peripheral Enthesitis in Metabolic Syndrome: A Retrospective Clinical and Power Doppler Ultrasound Study

OBJECTIVES

To investigate peripheral enthesitis with power Doppler ultrasound (PDUS) in patients presenting low back pain (LBP) and metabolic syndrome (MetS) in comparison with patients with only LBP, to correlate US scores with clinical-anthropometric characteristics, and to define any relationship between enthesitis and concurrent diffuse idiopathic hyperostosis syndrome (DISH).

METHODS

Sixty outpatients with LBP and MetS, evaluated with multi-site entheseal PDUS, scoring inflammatory and structural damage changes, were retrospectively analyzed. A group of 60 subjects with LBP, without MetS and evaluated with the same protocol, was analyzed as the control group.

RESULTS

Patients showed overweight (BMI 29.8) and low-grade inflammatory state (C-reactive protein [CRP] 0.58mg/dL, erythrosedimentation rate [ESR] 20.2mm/h). Enthesitis was demonstrated in 52 (86%) patients (17.6% entheses), and in 8 controls (13.3%) (p<.00001). PD signals (15% of patients) were associated with entheseal pain (p=.0138). US scores correlated with body mass index (BMI), pain, type 2 diabetes. In 28 (46%) patients a concurrent DISH was diagnosed, correlating with older age (p<.0001), CRP (p=.0428), ESR (p=.0069) and PDUS scores (p=.0312 inflammatory, p=.0071 structural). MetS had a strong association (OR 4.375, p=.0007) with concurrent DISH.

CONCLUSIONS

Diffuse peripheral enthesitis is very common in MetS. Almost half of MetS patients can have a concurrent diagnosis of DISH; they are older, with higher inflammation, and higher PDUS enthesitis scores.

The application of musculoskeletal ultrasonography in sports injuries of lower limbs in Chongqing Marathon competition

BACKGROUND

High incidence of sports injury occurring during marathon competitions urges a pressing demand for a convenient and accurate diagnostic tool of such injuries. However, contemporary information on the application of musculoskeletal ultrasonography (MSUS) in sports injury is not sufficient.

METHODS

A repeated measures study was used to describe the distribution of lower limb injuries in the Chongqing marathon and the application of MSUS in assessing these sports injuries. To verify the diagnostic accuracy of MSUS for sports injury, participants were assigned to group A (MSUS group) or group B (Sports medicine physician, i.e. SMP group), each group had an independent procedure of making a diagnosis. That is, ultrasound physicians in group A made a diagnosis from the ultrasonographic images while sports medicine physicians in group B synthesizing symptoms and signs of patients to identify the exact injury.

RESULTS

No statistically significant difference was found in the participants of the baseline characteristics between the two groups (P>0.05). In both groups, the knee was accounted as the vast majority of running injury sites, followed by the ankle (P=0.152). Tendons and ligaments injuries (χ2=48.437 and P=0.000) were the most common types of injury. Visual Analog Scale (VAS), a higher score of which indicates severer pain (0 to 10), was used to evaluate the severity of pain from injuries. VAS scores decreased significantly (P<0.05) in both groups after immediate treatment and the decrease in group A was significantly greater than group B (P=0.007). For athletes with pain sustained or exacerbated, further MRI exam showed a concordance rate of approximately 100% between MSUS and MRI diagnosis.

CONCLUSIONS

Musculoskeletal ultrasonography could be applied as an efficient method for the diagnosis of sports injuries in the athletic competition field.

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

Objective.

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

Methods.

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

Results.

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

Conclusion.

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

Ultrasound of entheses in ankylosing spondylitis patients: The importance of the calcaneal and quadriceps entheses for differentiating patients from healthy individuals

OBJECTIVES

To compare the ultrasonographic findings of entheses in ankylosing spondylitis (AS) patients with those of healthy control individuals and to assess the ability of ultrasound (US) to identify aspects related to the disease.

METHODS

A cross-sectional study involving 50 patients with AS and 30 healthy controls was performed. Clinical assessment included the use of a visual analog scale for pain, assessment of swelling of the enthesis, global assessments for patients and physician, use of a disease activity index, mobility and dysfunctional indices, erythrocyte sedimentation rate and clinical enthesitis index. US was performed for the following entheses by two experienced musculoskeletal radiologists: brachial triceps, distal quadriceps, proximal and distal patellar tendons, calcaneal tendon, and plantar fascia; the total and subitems of the Madrid Sonographic Enthesitis Index were used for evaluations.

RESULTS

Comparison between groups showed a statistically significant difference with worse scores in AS patients, with bone erosion of the calcaneal enthesis and bone erosion and thickening of the plantar fascia. The odds ratio for thickening of the plantar fascia in the AS group was 3.47, according to logistic regression analysis. The AS group also had worse scores regarding the presence of calcification in the quadriceps enthesis, with a fivefold increased risk.

CONCLUSION

US analysis showed that only entheses of the foot and quadriceps were able to differentiate AS patients from healthy individuals.

Whole-body Magnetic Resonance Imaging in Axial Spondyloarthritis: Reduction of Sacroiliac, Spinal, and Entheseal Inflammation in a Placebo-controlled Trial of Adalimumab

Objective.

To investigate whether adalimumab (ADA) reduces whole-body (WB-) magnetic resonance imaging (MRI) indices for inflammation in the entheses, peripheral joints, sacroiliac joints, spine, and the entire body in patients with axial spondyloarthritis (axSpA).

Methods.

An investigator-initiated, randomized, placebo-controlled, double-blinded 48-week followup trial included 49 patients with axSpA, who had Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) ≥ 4.0 despite treatment with nonsteroidal antiinflammatory drugs and a clinical indication for tumor necrosis factor inhibitor treatment. Patients were randomized to subcutaneous ADA 40 mg or placebo every other week for 6 weeks; thereafter, all patients received ADA. Conventional MRI and WBMRI were performed at weeks 0, 6, 24, and 48. The primary WBMRI endpoint was the proportion of patients with an improvement in WBMRI total inflammation index above the smallest detectable change (SDC) at Week 6.

Results.

The primary WBMRI endpoint (improvement of SDC > 2.3) was met in 11 (44%) patients in the ADA group and 3 (13%) patients in the placebo group (p = 0.025, Fisher’s exact test). The primary conventional MRI endpoint, the minimally important change in Spondyloarthritis Research Consortium of Canada Spine MRI Inflammation Index at Week 6, was achieved by 9 (36%) patients in the ADA group and 4 (17%) patients in the placebo group (p = 0.20). The primary clinical endpoint, BASDAI reduction > 50% or 2.0 at Week 24, was attained by 32 (65%) patients.

Conclusion.

ADA provided significant reductions in WBMRI indices of peripheral, axial, and whole-body inflammation in patients with axSpA. WBMRI is promising for objective assessment and monitoring of peripheral and axial disease activity in future clinical trials.

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.

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.

The assessment of lesions of the Achilles tendon by ultrasound imaging in inflammatory arthritis: A systematic review and meta-analysis

OBJECTIVE

Ultrasound (US) is a highly sensitive, reliable and non-invasive tool, which allows for the assessment of lesions of tendons and entheseal sites. The aim of this systematic review and meta-analysis is to identify differences in US lesions of the Achilles tendon (AT) between people with inflammatory arthritis (IA) and healthy controls.

METHODS

An electronic literature search was performed on Medline, CINAHL, SportDiscus and The Cochrane Library. Methodological quality was assessed using a modified Quality Index. Odds ratios with 95% confidence intervals (CI) were determined. Meta-analysis was conducted on those studies that were considered to be homogenous.

RESULTS

A total of 13 high-to-medium quality studies met the inclusion criteria. The majority of studies reported US lesions in spondyloarthropathy (SpA), with limited evidence for other forms of IA. US lesions were not consistently defined with regard to Outcome Measures in Rheumatology Clinical Trials (OMERACT) definitions, and numerous scoring systems were used across the majority of studies. The mean AT thickness at the enthesis in people with SpA was 0.54mm thicker (95% CI: 0.10-0.97mm) with more frequent erosions in people with SpA (odds ratio = 7.43, 95% CI: 1.99-27.77, P = 0.003) and rheumatoid arthritis (RA) (odds ratio = 9.60, 95% CI: 1.23-74.94, P = 0.03), compared to controls. There was no significant difference in the frequency of enthesophyte formation in people with SpA compared to the controls (odds ratio = 2.48, 95% CI: 0.64-9.70, P = 0.19).

CONCLUSIONS

The systematic review identified that a majority of studies reporting US lesions were in SpA, but limited evidence relating to other forms of IA. Consistent application of the OMERACT US definitions and scoring of US lesions is required in future studies of AT disease in IA. Further work is also required to distinguish between US lesions reflective of inflammation and structural damage.

Novel imaging modalities in spondyloarthritis

Novel imaging techniques have emerged in the field of spondyloarthritis. This article will cover the role of, and the sensitivity and specificity of magnetic resonance imaging (MRI) and ultrasound in the diagnosis and monitoring of axial and peripheral SpA. It will discuss how the definition of a 'positive MRI' of the sacroiliac joints and spine is evolving. Differential diagnoses of inflammatory lesions of both the sacroiliac joints and the spine are addressed due to their importance in image interpretation. The article will also discuss the role of sonography in assessing peripheral entheses, joints, tendon sheaths, nails and soft tissues. The utility for clinical as well as an outcome measure will be discussed. We finally aim to give guidance on when and how to use these new modalities and on how to analyse and interpret the imaging findings in daily practice.

Imaging the hard/soft tissue interface

Interfaces between different tissues play an essential role in the biomechanics of native tissues and their recapitulation is now recognized as critical to function. As a consequence, imaging the hard/soft tissue interface has become increasingly important in the area of tissue engineering. Particularly as several biotechnology based products have made it onto the market or are close to human trials and an understanding of their function and development is essential. A range of imaging modalities have been developed that allow a wealth of information on the morphological and physical properties of samples to be obtained non-destructively in vivo or via destructive means. This review summarizes the use of a selection of imaging modalities on interfaces to date considering the strengths and weaknesses of each. We will also consider techniques which have not yet been utilized to their full potential or are likely to play a role in future work in the area.