Ultrasonography in rheumatoid arthritis: what rheumatologists should know

Clinical Application of Ultra-High-Frequency Ultrasound

Musculoskeletal ultrasound involves the study of many superficial targets, especially in the hands, wrists, and feet. Many of these areas are within the first 3 cm of the skin surface and are ideal targets for ultra-high-frequency ultrasound. The high spatial resolution and the superb image quality achievable allow foreseeing a wider use of this novel technique, which has the potential to bring innovation to diagnostic imaging.

Assessment of disease activity with simplified joint ultrasonography method in rheumatoid arthritis patients

Background/Aim: Ultrasound (US) is a highly useful tool for assessing the disease activity of rheumatoid arthritis (RA). On the other hand, examining all joints could be time-consuming and unfeasible. Defining the number of joints and which joints should be tested is essential to accurately measuring RA activity. Several simplified US methods are undergoing development for this purpose. The aim of this study was to assess the correlation between simplified 12-joint US findings and physical examination findings/disease activity in RA patients. Methods: This cohort study included 62 RA patients who had been undergoing treatment for at least three months. Multiplanar grayscale images and power Doppler (PD) of the 12 joints (bilateral elbow, wrist, second and third metacarpophalangeal [MCP] joints, knee, and ankle) were acquired and compared with clinical assessments. Disease activity was assessed using the clinical disease activity and simplified disease activity indices and disease activity score-28 (CDAI, SDAI, and DAS28, respectively). Synovial effusion, synovial proliferation, and PD US scores were calculated for 12 joints. Correlations between US scores and disease activity, clinical examination, and acute phase reactants were assessed. Results: The number of joints with PD activity and US total and US synovial proliferation scores showed weak correlations with clinical activity scores (r = 0.25, r = 0.26, and r = 0.28 for SDAI and r = 0.23, r = 0.26, and r = 0.28 for DAS28, respectively). The CDAI did not present any statistically significant correlations. The agreement between US findings and clinical joint examination was generally weak. PD activities of the second MCP joints (r = 0.84, P < 0.01) and knees (r = 0.42, P < 0.01) mostly correlated with clinical examination although it was weakly correlated at the third MCP (r = 0.152) and wrist (r = 0.148), and not correlated at the elbow (r = 0.125). Conclusion: The weak correlation between US findings and clinical examination/disease activity suggests that clinical examination alone may not be sufficient to determine joint inflammation and disease activity. US could provide a more accurate assessment of RA patients and aid in medication selection.

Ultrasonography supplements clinical exam to improve early rheumatoid arthritis disease activity monitoring in metatarsophalangeal joints

INTRODUCTION

Compared with clinical examination (CE), ultrasonography (US) provides additional and more accurate assessment of inflammation and visualization of structural damage. To better understand the effectiveness of US in metatarsophalangeal joints (MTPJs), we compared disease activity in MTPJs 2-5 assessed by CE and US, with magnetic resonance imaging (MRI) as reference standard.

METHOD

Treatment-naïve adult patients with early RA (ACR criteria, disease duration < 2 years) were consecutively recruited. MTPJs 2-5 were assessed for swelling and tenderness, and imaged by US (Esaote MyLab70). The most symptomatic foot was imaged by peripheral MRI (1.0 Tesla). US was semiquantitatively graded for synovial thickening (ST) and power Doppler (PD) (0-3), and erosions (yes/no). MRI was semiquantitatively graded for bone marrow edema (BME), synovitis, and erosions (OMERACT). Kappa agreement, sensitivity, specificity, and predictive values were analyzed using cut-offs at ST ≥ 2, PD ≥ 1, and MRI synovitis and BME at both ≥ 1 and ≥ 2.

RESULTS

This study included 39 patients (85% female, mean (SD) age = 51.6 (10.3)). Using MRI synovitis and BME grade ≥ 2 as the reference, PD had superior sensitivity (82%) and kappa agreement (k = 0.43) than swollen joint count (55%, k = 0.20), but similar high specificity (88%, 83%). ST and PD were often observed in clinically asymptomatic MTPJs. US detected very few MRI erosions, but several observed erosions corresponded to grade ≥ 2 MRI erosions.

CONCLUSION

Clinical swelling and PD are highly specific for active inflammation in the MTPJs. US supplemented CE by allowing observation of subclinical inflammation and structural damage. Key Points • Ultrasonography detected many subclinical synovial inflammations in metatarsophalangeal joints (MTPJs), many confirmed by MRI • Ultrasonography may best be used clinically to supplement clinical examination by assessing non-swollen joints • Ultrasonography provided quick method of visualizing bone erosions that were grade ≥ 2 on MRI.

Retrospective study of sonographic findings in bone involvement associated with rotator cuff calcific tendinopathy: preliminary results of a case series

Objective

The present study was aimed at investigating bone involvement secondary to rotator cuff calcific tendonitis at ultrasonography.

Materials and Methods

Retrospective study of a case series. The authors reviewed shoulder ultrasonography reports of 141 patients diagnosed with rotator cuff calcific tendonitis, collected from the computer-based data records of their institution over a four-year period. Imaging findings were retrospectively and consensually analyzed by two experienced musculoskeletal radiologists looking for bone involvement associated with calcific tendonitis. Only the cases confirmed by computed tomography were considered for descriptive analysis.

Results

Sonographic findings of calcific tendinopathy with bone involvement were observed in 7/141 (~ 5%) patients (mean age, 50.9 years; age range, 42-58 years; 42% female). Cortical bone erosion adjacent to tendon calcification was the most common finding, observed in 7/7 cases. Signs of intraosseous migration were found in 3/7 cases, and subcortical cysts in 2/7 cases. The findings were confirmed by computed tomography. Calcifications associated with bone abnormalities showed no acoustic shadowing at ultrasonography, favoring the hypothesis of resorption phase of the disease.

Conclusion

Preliminary results of the present study suggest that ultrasonography can identify bone abnormalities secondary to rotator cuff calcific tendinopathy, particularly the presence of cortical bone erosion.