Bone erosions in rheumatoid arthritis: better to see more?

Diagnostic value of Ultrasonography in the detection of Bone Erosions in patients with Rheumatoid Arthritis: a comparison with Conventional Radiography

OBJECTIVE

Rheumatoid arthritis (AR) is the most common systemic inflammatory disease of joints, with prevalence of 1% worldwide. Bone erosion (BE) is a central feature of rheumatoid arthritis and is associated with disease severity and poor functional outcome. Conventional Radiography (CR) and Ultrasonography (US) play an important role in the diagnosis of RA. The aim of this study was to compare the value of two methods in the detection of BE in AR patients.

METHODS

In this cross-sectional study, 111 patients with confirmed RA have been randomly selected and were studied. A checklist which includes demographic information such as age, gender, place of residence, history of smoking, education level and history of rheumatologic disease was completed for all patients, and then radiography and high-resolution US of dominant hands and wrists of metacarpophalangeal (MCP) joint were performed. Collected data was analysed by statistical methods in SPSS version 22.

RESULTS

The results of this study showed that there is no significant difference between these two methods in detection of BE. In age groups < 44 years old, US with 98% had more sensitivity than CR with 89%.

CONCLUSION

Results showed that there is no significant difference in diagnostic value of US in bone erosion in patients with rheumatoid arthritis, in comparison with CR in terms of gender and diagnosis for the existence of erosions; however, in determining the amount of BE in age groups < 44 years old, US has better performance than CR.

The SPECTRA Collaboration OMERACT Special Interest Group: Current Research and Future Directions

OBJECTIVE

High-resolution peripheral quantitative computed tomography (HR-pQCT) has the potential to improve radiographic progression determination in clinical trials and longitudinal observational studies. The goal of this work was to describe the current state of research presented at Outcome Measures in Rheumatology (OMERACT) 2016 and ensuing future directions outlined during discussion among attendees.

METHODS

At OMERACT 2016, SPECTRA (Study grouP for xtrEme-Computed Tomography in Rheumatoid Arthritis) introduced efforts to (1) validate the HR-pQCT according to OMERACT guidelines, focusing on rheumatoid arthritis (RA), and (2) find alternatives for automated joint space width (JSW) analysis. The Special Interest Group (SIG) was presented to patient research partners, physicians/researchers, and SIG leaders followed by a 40-min discussion on future directions.

RESULTS

A consensus definition for RA erosion using HR-pQCT was demonstrated through a systematic literature review and a Delphi exercise. Histopathology and perfusion studies were presented that analyzed the true characteristics of cortical breaks in HR-pQCT images, and to provide criterion validity. Results indicate that readers were able to discriminate between erosion and small vascular channels. Moderate reliability (ICC 0.206-0.871) of direct erosion size measures was shown, which improved (> 0.9) only when experienced readers were considered. Quantification of erosion size was presented for scoring, direct measurement, and volumetric approaches, as well as a reliability exercise for direct measurement. Three methods for JSW measurement were compared, all indicating excellent reproducibility with differences at the extremes (i.e., near-zero and joint edge thickness).

CONCLUSION

Initial reports on HR-pQCT are promising; however, to consider its use in clinical trials and longitudinal observational studies, it is imperative to assess the responsiveness of erosion measurement quantification.

Heterogeneity of Cortical Breaks in Hand Joints of Patients with Rheumatoid Arthritis and Healthy Controls Imaged by High-resolution Peripheral Quantitative Computed Tomography

Objective.

Conventional radiographs (CR) of the hands are the gold standard for imaging bone erosions. The presence of bone erosions, reflected by the presence of cortical breaks, is a poor prognostic factor in patients with rheumatoid arthritis (RA). The availability of high-resolution peripheral quantitative computed tomography (HR-pQCT) enables detailed investigation of cortical breaks in rheumatic diseases. The aim of this image review is to show HR-pQCT images of the spectrum of cortical breaks with and without underlying trabecular bone changes in metacarpophalangeal (MCP) joints of healthy controls (HC) and patients with RA, with corresponding images on CR and magnetic resonance imaging (MRI).

Methods.

Second and third MCP joints of 41 patients (of which 10 were early RA with ≤ 2 years and 24 longstanding RA with ≥ 10 years of disease duration) and 38 HC were imaged by CR, MRI, and HR-pQCT (XtremeCT1, Scanco Medical AG). Representative images of the spectrum of cortical breaks were selected.

Results.

Cortical breaks were found in early and longstanding RA, but also in HC. They were heterogeneous in size, location, and number per joint, with a variety of surrounding cortical and underlying trabecular bone characteristics.

Conclusion.

Using HR-pQCT images of MCP joints, heterogeneous cortical breaks with and without surrounding trabecular bone changes were found, not only in RA but also in HC. The underlying mechanisms and significance of this spectrum of cortical breaks as found with high 3-D resolution needs further investigation.

High-resolution imaging of bone and joint architecture in rheumatoid arthritis

INTRODUCTION

Rheumatoid arthritis (RA) is characterized by local and systemic bone loss caused by increased bone resorption. We describe the current utilization of high-resolution peripheral quantitative computed tomography (HR-pQCT) in the evaluation of bone and joint in RA.

SOURCES OF DATA

PubMed was searched for publications using keywords that included 'bone microarchitecture', 'high-resolution peripheral quantitative computed tomography' and 'rheumatoid arthritis'.

AREAS OF AGREEMENT

HR-pQCT may simultaneously allow assessment of trabecular and cortical bone parameters and be a useful method for depicting bone erosions.

AREAS OF CONTROVERSY

HR-pQCT only assesses bone microarchitecture at the distal radius and tibia. Controversy exists regarding the optimal way to differentiate cortical and trabecular regions.

GROWING POINTS

Although HR-pQCT is currently a research tool, there is potential for its use in the clinical diagnosis and management in RA. Further research is required to evaluate the clinical relevance of imaging abnormalities identified in RA patients.