Background: Enthesitis is a remarkable feature of ankylosing spondylitis (AS) not specifically approached by the available measuring tools for the disease. Ultrasonography (US) has proved to be an excellent technique for the assessment of tendon pathology. Objective: To test a Sonographic Entheseal Index (SEI) of the lower limbs in a cohort of patients with AS, as a potential measuring tool. Methods: 44 patients with AS and 10 healthy controls were enrolled. Bath Ankylosing Spondylitis Functional Index and Bath Ankylosing Spondylitis Disease Activity Index, pain at entheseal points, severity of symptoms, acute-phase reactants, Schober's test and stage of sacroiliitis were recorded. Patients underwent US examination of five entheseal regions from both lower limbs by two experts. Hypoechogenicity, increased tendon thickness, peritendinous oedema and bursitis were considered signs of active inflammation. Insertional bone erosions, intratendinous calcifications, decreased thickness and tears were considered signs of chronic injury. Each alteration independently scored one point. Data were analysed with Spearman's correlation method. Results: A significant interobserver correlation in SEI scores (p,0.001) and a fine discriminative power between controls and patients were observed. Acute entheseal lesions predominated (63% vs 37%), the most frequent alteration being tendon hypoechogenicity (43%). 72% of all lesions were located at the foot. The SEI correlated with reduction of Schober's test (p,0.02), but not with other activity or severity parameters. Conclusions: A scoring method such as the SEI may be of help in characterising entheseal injury in AS, and for decision making in these patients.

Objective. Ultrasound (US) has been shown to be a sensitive tool for evaluating synovitis in rheumatoid arthritis. However, the validity of US has not yet been established in juvenile idiopathic arthritis (JIA). The purpose of this study was to assess the validity of US for detecting synovitis for both diagnosis and followup in JIA. Methods. A systematic literature search in Embase and PubMed was performed before February 25, 2011. Selection criteria included original articles on children, JIA, US, Doppler, synovitis, and management published in the English language. Data were extracted from the articles meeting the inclusion criteria, particularly those focused on the US definition of synovitis, scoring systems used, and metric properties studied. The type and number of joints tested, study design, and quality of the studies were assessed. Results. Twenty studies were identified using US to assess synovitis in JIA. The knee was the joint most commonly studied in these articles. There was heterogeneity regarding the US definition and quantification of synovitis. Synovitis was commonly assessed by using gray scale and only a few studies included the Doppler technique. Construct validity was reported in 80% of articles, including the clinical examination as the main comparator. US demonstrated higher sensitivity in detecting synovitis as compared to clinical examination. Few studies reported US reliability and responsiveness in JIA. Conclusion. US is a valuable tool for detecting synovitis in JIA, and demonstrated higher sensitivity in assessing synovitis as compared to clinical examination. However, further studies are needed for evaluating the reliability and responsiveness to assess synovitis changes over time.

US seems a promising tool for evaluating inflammatory tendon lesions. However, further validation is necessary for implementation in clinical practice and trials.

Results. Of 60 patients (67 anatomic areas), MSUS was considered as necessary after clinical examination in 39 patients (65%), totaling 43 anatomic areas (64.17%). An overall change of the initial clinical diagnosis was present in 60% of the anatomic areas (P ‫؍‬ 0.0175). In all of the anatomic areas (100%), the new diagnosis was more objective and detailed. An overall change of the initial systemic therapy was present in 25% of anatomic areas (P ‫؍‬ 0.0014) and in 36% of anatomic areas (P ‫؍‬ 0.095) for local therapy. A guided diagnostic aspiration was decided to be performed in 15% of anatomic areas and a guided therapeutic injection in 22% of anatomic areas. Conclusion. Enhanced information obtained by MSUS evaluation leads to changes, with a significant impact on the initial diagnosis and treatment strategy designed after clinical examination.