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

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.

Effect of Enthesitis on 1505 Brazilian Patients with Spondyloarthritis

Objective.

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

Methods.

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

Results.

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

Conclusion.

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

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.