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

Abstract

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.

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

“…In a recent cross‐sectional study on 50 patients with AS and 30 healthy controls to compare the ultrasonographic findings of entheses in AS patients and controls, bone erosion in the calcaneal enthesis and the plantar fascia, and plantar thickening were statistically more prominent in the AS group . Similarly, the bone profile scores reflecting the erosions were also higher in AS and nr‐axSpA patients than controls in our study.…”

Ultrasound for ankle and foot pathologies in early rheumatoid arthritis

“…28 The early signs of AS often appear as enthesis inflammation, 29,30 which may be detected by power Doppler ultrasound (PDUS) through the presence of bone erosion, pathological structural changes, and thickening of the tendon at the site of insertion. 31 The capability of ultrasound to detect changes in the entheses may allow early diagnosis of AS, as supported by a systematic review supporting that musculoskeletal ultrasound was effective in facilitating the diagnosis of AS, despite there was still a room for improvement of its utility for the evaluation of the disease activity of AS. 32 Overall, the potential of using ultrasound for early detection of other autoimmune diseases including AS and PsA would require further investigation.…”

“…Lastly, we are interested in the possibility of utilizing ultrasound to diagnose other inflammatory arthritis or autoimmune diseases and their comorbidities, 14‐18 such as ankylosing spondylitis (AS) 19 or psoriatic arthritis (PsA), 20‐23 juvenile idiopathic arthritis, 24,25 osteoarthritis, 26,27 or fibromyalgia 28 . The early signs of AS often appear as enthesis inflammation, 29,30 which may be detected by power Doppler ultrasound (PDUS) through the presence of bone erosion, pathological structural changes, and thickening of the tendon at the site of insertion 31 . The capability of ultrasound to detect changes in the entheses may allow early diagnosis of AS, as supported by a systematic review supporting that musculoskeletal ultrasound was effective in facilitating the diagnosis of AS, despite there was still a room for improvement of its utility for the evaluation of the disease activity of AS 32 .…”

One year in review 2021: axial spondyloarthritis

“…Ultrasound (US) is known to have a central role in the evaluation of peripheral involvement in axSpA. US study of calcaneal and quadriceps entheses was found to be able to distinguish AS patients from healthy controls in a cross-sectional study, showing worse scores of the Madrid Sonographic Enthesitis Index with bone erosion of the calcaneal enthesis, bone erosion and thickening of the plantar fascia and the presence of calcification in the quadriceps enthesis (32).…”