Doppler enthesitis: a potential useful outcome in the assessment of axial spondyloarthritis and psoriatic arthritis

Ultrasound assessment of Achilles enthesitis: a dedicated training program

OBJECTIVE

To describe an intensive and multimodal ultrasound (US) training program focused on Achilles enthesitis and to illustrate the learning curve of trainees without experience.

METHODS

Three medical students (trainees) and two rheumatologists experienced in musculoskeletal US (trainers) were involved in the training program, which encompassed one preliminary theoretical-practical meeting and five scanning sessions (two patients per session). The students and one expert performed the US examination of the Achilles enthesis bilaterally. The trainees acquired representative images and assessed the presence of Outcome Measures in Rheumatology (OMERACT) US abnormalities of enthesitis. The experts provided feedback addressing trainees' misinterpretations, and the quality of the acquired images was evaluated. A dedicated questionnaire was used to evaluate the students' confidence. After each session, five sets of static images (total=100 images of most commonly scanned entheses) were provided and scored by the students according to OMERACT US definitions. Total agreement and prevalence and bias adjusted kappa (PABAK) were used to evaluate the concordance between the trainees and the expert sonographer.

RESULTS

The total agreement and PABAK significantly improved between the first and fifth scanning sessions (76.2% versus 92.9%, p<0.01, and 0.5 versus 0.79, p<0.01) and between the first and fifth static image sets (64.5% versus 81.9%, p<0.01, and 0.29 versus 0.74, p<0.01). Image quality did not significantly improve (p=0.34). A significant increase in trainees' confidence was registered (p<0.01).

CONCLUSIONS

The described training program rapidly improved the students' performance in the US assessment of Achilles enthesitis, appearing to be an effective starting model for the future development of pathology-oriented teaching programs for the US in rheumatology.

2D shear wave elastography for the assessment of quadriceps entheses-a methodological study

OBJECTIVE

To establish the scanning protocol for 2-dimensional shear wave elastography (SWE) on normal entheses by investigating the possible confounding factors that may increase the variability of measured elasticity.

MATERIAL AND METHODS

30 normal quadriceps entheses were scanned using SWE to compare the stiffness and coefficient variation by changing the ultrasonic coupling gel thickness, knee position, region of interest size, and scanning plane.

RESULTS

No significant difference in median shear wave velocity (SWV) was observed in different coupling gel thicknesses. The median SWV was higher in the knee flexion position than in the extended position (p < 0.001). Increased knee flexion led to stiffer quadriceps enthesis and higher SWV (ρ = 0.8, p < 0.001). The median SWV was higher when the diameter region of interest was 4.0 mm than 2.0 mm (p = 0.001). The median SWV was higher in the transverse plane than in the longitudinal plane (p < 0.001). Strong correlation was found between SWV and the degree of the shear wave to muscle fiber direction (ρ = 0.8, p < 0.001). The coefficient variation was lower in a gel thickness of 2.5 cm, with an extended knee, a region of interest of 2.0 mm, and a longitudinal plane (p > 0.05). For interobserver reliability for the proposed protocol, the intraclass correlation coefficients was 0.763.

CONCLUSION

In this study, we determined supine position with the knee extended; using 2.0 mm diameter region of interest and image acquisition at the longitudinal plane with thicker layer coupling gel seems most appropriate to reliably image healthy quadriceps entheses with SWE.

Effects of secukinumab on synovitis and enthesitis in patients with psoriatic arthritis: 52-week clinical and ultrasound results from the randomised, double-blind ULTIMATE trial with open label extension

OBJECTIVES

In the ULTIMATE study with an open label extension, we assessed the long-term effect of secukinumab at tissue level on synovitis and enthesitis, and across all psoriatic arthritis (PsA) manifestations, using both clinical evaluations and power Doppler ultrasonography (PDUS).

METHODS

This randomised, placebo-controlled, Phase 3 study (ULTIMATE) included biologic-naïve patients with PsA with active PDUS synovitis and clinical enthesitis, and inadequate response to conventional synthetic disease-modifying antirheumatic drugs. The study consisted of 3 treatment periods; in the first period (baseline to week 12) patients were randomised to receive subcutaneous secukinumab (150 mg or 300 mg according to severity of skin psoriasis) or placebo every week until week 4 and once every 4 weeks up to week 12. In the second period (weeks 12-24) all patients received open-label secukinumab with placebo patients switching to secukinumab (150 mg or 300 mg). The third period (weeks 24-52) was an extended open-label treatment period. The long-term responsiveness of the Global EULAR-OMERACT Synovitis Score (GLOESS), clinical enthesitis and global PDUS-detected enthesitis score (using two candidate definitions of activity) at patient level, together with clinical efficacy across key manifestations of PsA and safety were assessed.

RESULTS

Of the 166 patients enrolled, 144 completed week 52. A significant reduction in GLOESS was demonstrated in the secukinumab group vs placebo at week 12, followed by a stable reduction of synovitis until week 52 in the secukinumab group while placebo switchers from week 12 reached a similar level of reduction at week 24 with stability thereafter. Likewise, a significant reduction in the Spondyloarthritis Research Consortium of Canada (SPARCC) enthesitis index was shown in the secukinumab group vs placebo at week 12 with sustained improvement to week 52. Global OMERACT PDUS enthesitis scores were numerically lower in secukinumab vs placebo switchers in the first two treatment periods, with some stability in the third period in both groups. Improvements in clinical responses were also observed across all key domains of PsA up to week 52 in both treatment groups with no new or unexpected safety signals.

CONCLUSIONS

ULTIMATE showed consistent improvements in clinically and ultrasound-assessed synovitis and enthesitis and sustained clinical efficacy through week 52 in patients with PsA treated with secukinumab and placebo switched to secukinumab.

Seeing is believing: Smart use of musculoskeletal ultrasound in rheumatology practice

Musculoskeletal ultrasonography has become an increasingly valuable tool as a complement to the physical exam in rheumatology practice. Its point-of-care access, low cost, safety, portability, and reliability in trained hands, make this technique especially useful in patients with inflammatory arthritis. Growing evidence has demonstrated the value of musculoskeletal ultrasound in the detection of inflammatory and structural changes in patients with joint pain without obvious joint swelling, in differentiating various inflammatory diagnoses, in the monitoring of inflammatory arthritis, and interventional procedures. The potential role of ultrasound guiding treat-to-target strategies or tapering treatment in inflammatory arthritis requires further research. However, musculoskeletal ultrasound can also have pitfalls and limitations that a clinician should be aware of.

18F-sodium fluoride PET-CT visualizes both axial and peripheral new bone formation in psoriatic arthritis patients

PURPOSE

As bone formation is associated with psoriatic arthritis (PsA), positron emission tomography (PET) using a ¹⁸F-Fluoride tracer may enable sensitive detection of disease activity. Our primary aim was to determine the feasibility of whole-body ¹⁸F-sodium fluoride PET-CT in clinically active PsA patients to depict new bone formation (as a reflection of disease activity) at peripheral joints and entheses. Our secondary aim was to describe ¹⁸F-sodium fluoride findings in the axial skeleton.

METHODS

Sixteen patients (female 10/16, age 50.6 ± 8.9 years) with PsA fulfilling CASPAR criteria or with a clinical diagnosis of PsA according to the treating rheumatologist and with ≥ 1 clinically active enthesitis site were included. Of each patient, a whole-body ¹⁸F-sodium fluoride PET-CT scan was performed. All scans were scored for PET-positive lesions at peripheral joints, enthesis sites and the spine. Clinical disease activity was assessed by swollen/tender joint count 44, enthesitis according to MASES and SPARCC scores.

RESULTS

Out of 1088 evaluated joints, 109 joints showed PET enhancement, mainly in the interphalangeal and metatarsal joints of the feet (14/109, 12.9%) and the distal interphalangeal joints of the hands (14/109, 12.9%). PET positivity was found at 44/464 enthesis sites, mainly at the patella tendon insertion (11/44, 25%) and quadriceps tendon insertion (10/44, 22.7%). Of the PET-positive joints and enthesis sites, respectively 18.2% and 29.5% were clinically positive; 81.8% and 70.5% of the PET-positive joints and entheses respectively were clinically asymptomatic. In 11 patients, ≥ 1 axial PET-positive lesion was observed, mainly in the cervical spine.

CONCLUSIONS

New molecular bone formation was observed on ¹⁸F-sodium fluoride PET-CT scans, in all domains in which PsA disease activity can be observed, with a substantial part showing no clinical symptoms.

CLINICAL TRIAL REGISTRATION

EudraCT: 2017-004,850-40, registered on 13 December 2017.

Ultrasound Enthesitis in Psoriasis Patients with or without Psoriatic Arthritis, a Cross-Sectional Analysis

Background and objectives: The main objective of the current study was to describe the prevalence of enthesitis at different sites in a group of patients with psoriasis with or without psoriatic arthritis (PsA). Materials and Methods: The study included adult patients with psoriasis who underwent clinical examination, laboratory tests and ultrasound examination of the entheses. The enthesitis ultrasound scores (BUSES, MASEI, GUESS) were evaluated; the presence of OMERACT-defined enthesitis was also recorded for each scan site. Results: The study included 16 (57.1%) patients with PsA and 12 (42.9%) patients with psoriasis, with an increased average body mass index (29.3 kg/m2). Compared to psoriasis patients, PsA patients had a higher prevalence of nail psoriasis (68.8% compared to 33.3%; p = 0.063). There were no significant differences regarding the clinical examination of entheses between patients with psoriasis and patients with PsA (p = 0.459). Ultrasound scores, BUSES, GUESS and MASEI proved to have statistically significant higher median values in PsA patients compared to psoriasis patients. Compared to psoriasis patients, PsA patients had a significantly higher prevalence of OMERACT-defined enthesitis of the quadriceps tendon and inferior patellar ligament (both 81.3% compared to 25.0%, p = 0.003). Clinical examination of the lateral epicondyle and of the superior patellar ligament was consistent with their ultrasound examination (κ = 0.357, p = 0.043, respectively, κ = 0.404, p = 0.008). Conclusions: Clinical enthesitis scores do not differ between psoriasis and PsA patients. All analyzed ultrasound scores are significantly higher in patients with PsA. OMERACT-defined enthesitis has the ability to discriminate sonographic enthesitis between the two subgroups for bilateral quadriceps and inferior patellar tendon enthesitis. Bilateral ultrasound damage of entheses can suggest a PsA diagnosis.

Magnetic resonance imaging characteristics in patients with spondyloarthritis and clinical diagnosis of heel enthesitis: post hoc analysis from the phase 3 ACHILLES trial

Objective

To investigate the imaging characteristics and clinically assess heel enthesitis in spondyloarthritis (SpA) by applying in a post hoc analysis the Heel Enthesitis Magnetic Resonance Imaging Scoring system (HEMRIS) in blinded and centrally-read MRI data from the ACHILLES trial (NCT02771210).

Methods

ACHILLES included patients (≥18 years) with active psoriatic arthritis or axial SpA with clinical and MRI-positive heel enthesitis refractory to standard treatment. Patients were randomized to receive subcutaneous secukinumab 150/300 mg or placebo. At week 24, patients on placebo were switched to secukinumab treatment. MRI-positive heel enthesitis was confirmed in all patients by local investigators. MRIs were performed at 3 timepoints: screening and weeks 24 and 52. In the present analysis, all MRIs were re-evaluated by 2 blinded central readers in a consensus read fashion for a priori defined MRI parameters based on HEMRIS.

Results

At screening, 171/204 (83.8%) of patients presented with entheseal inflammation and/or structural damage, considering both the Achilles tendon and plantar fascia. Pathologies were more evident in the Achilles tendon area compared to the plantar aponeurosis. The most frequent pathologies were intra-tendon hypersignal and retrocalcaneal bursitis. The mean total entheseal inflammation score at screening in the Achilles tendon area was 2.99 (N=204) and the mean change (standard deviation [SD]) from screening to weeks 24 and 52 was − 0.91 (1.99) and − 0.83 (2.12) in the secukinumab group vs − 0.48 (1.86) and − 0.80 (1.98) in the placebo-secukinumab group, respectively. The mean total structural damage score at screening was 1.36 (N=204) and the mean change (SD) from screening to weeks 24 and 52 was 0.00 (0.65) and − 0.06 (0.56) in the secukinumab group vs 0.08 (0.48) and 0.04 (0.75) in the placebo-secukinumab group, respectively.

Conclusions

Based on the newly developed HEMRIS, entheseal inflammation and/or structural damage was confirmed in 83.3% of ACHILLES patients. Pathologies were more evident in the Achilles tendon area compared to plantar fascia, with the inflammatory parameters being more responsive with secukinumab treatment compared to placebo. The present analysis, with detailed information on individual MRI parameters, contributes to the scientific debate on heel enthesitis.

Trial registration

ClinicalTrials.gov NCT02771210.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13075-022-02797-8.

Improving Imaging Modalities in Early Psoriatic Arthritis: The Role of Ultrasound in Early Diagnosis of Psoriatic Arthritis

Objective: Despite recent advances, early diagnosis of psoriatic arthritis (PsA) remains a challenge in clinical practice. Ultrasound (US) could be a useful tool for the diagnosis and management of PsA. The objective of this review was to determine the role of US in early diagnosis of PsA.

Methods: We have performed a literature review aiming to evaluate studies on US findings in psoriasis and their predictive value of progression to PsA, as well as studies on US features specific for PsA in comparison with other conditions.

Results: A total of 40 studies were included. Sixteen studies assessed US findings in psoriasis, of which only 3 prospectively evaluated the role of US in predicting progression to PsA. Patients with PsA had a greater frequency of US abnormalities, in particular enthesitis and Power Doppler(PD) signal compared to patients with psoriasis only. In the longitudinal studies, psoriatic patients with higher enthesopathy scores at baseline were more likely to progress to PsA. Twenty-four studies evaluated US abnormalities in PsA and compared them to other conditions. Most specific US features that distinguish PsA from psoriasis were PD signal and erosions in joints and entheses. Extra-synovial changes, including peri-tendinous dermal soft tissue oedema with associated PD signal and flexor tendon enthesopathy, as well as thickening of the pulleys in the flexor tendons were highly characteristic for PsA, as they were frequently found in PsA patients, but in none of the RA patients. US-detected entheseal abnormalities in particular erosions and PD signal were more frequent in patients with PsA compared to fibromyalgia.

Conclusion: Despite the wide use of US in PsA, more research is needed to identify predictive factors of progression to PsA in patients with psoriasis, as well as to determine most specific US features that differentiate PsA from other conditions.

A Systematic Review of the Inclusion of Non-Inflammatory Ultrasonographic Enthesopathy Findings in Enthesitis Scoring Indices

Ultrasound has advanced the diagnosis and management of patients with inflammatory rheumatic conditions. It can be used to identify and monitor enthesitis, a cardinal feature of spondyloarthropthies. Several enthesitis scoring systems utilizing ultrasound to determine entheseal involvement have been developed. These scoring systems generally rely on determining the presence or absence of erosions, tendon enlargement, power Doppler signal, or enthesophytes. This systematic review identified ultrasound scoring systems that have been utilized for evaluating enthesitis and what key components derive the score. Review of these scoring systems, however, demonstrated confounding as some of the score components including enthesophytes may be seen in non-inflammatory conditions and some components including erosions can be seen from chronic damage, but not necessarily indicate active inflammatory disease. What is furthermore limiting is that currently there is not an agreed upon term to describe non-inflammatory enthesopathies, further complicating these scoring systems. This review highlights the need for a more comprehensive ultrasound enthesopathy scoring index.