Page 85 - Imaging of Osteoarthritis and Rheumatoid Arthritis in Hand Joints

High-resolution MRI of cartilage in finger joints
Introduction
Hand osteoarthritis (OA) is a common disease, leading to pain and functional impairment in daily activities.1, 2 Current standard treatment options aim at symptom relief using pain medication or splinting both with limited effect. Disease modifying drugs to stop progression of hand OA are not yet available, but interest in researching these drugs for OA is increasing, and sensitive measures of structural joint damage are needed to evaluate of the effect of these drugs.
Traditionally conventional radiography has been used for the assessment of
hand OA structural features, and is currently the only imaging method approved
by the regulatory agencies for detecting disease modifying effects despite not
being able to visualize cartilage directly.3 Magnetic resonance imaging (MRI)
has the advantage that it can depict cartilage directly and is increasingly being
used as a structural outcome measure in clinical trials in knee OA.4, 5 While MRI
has contributed to increasing knowledge about the underlying mechanisms 5 in hand OA,6, 7 it is difficult to assess the thin cartilage layer in small hand joints
using standard clinical MRI coils.
Recently, a hand OA MRI scoring system (HOAMRIS) was developed by the OMERACT MRI task force group, for which good reliability was demonstrated in both cross-sectional and longitudinal settings. 8, 9 The system is used to rate bone damage, synovial inflammation, and loss of joint space, but does not include a direct cartilage damage score, as the thin cartilage layer in small hand joints could not be accurately assessed on the MRI images used for the creation and evaluation of the OMERACT HOAMRIS.10 However, it has been shown that with higher resolution images using dedicated MRI coils the cartilage of MCP joints can be measured reliably, 11 and it is to be expected that direct evaluation of cartilage is more accurate than indirect measurement of inter bone distance.
Hence, the aim of this study was to compare direct cartilage evaluation using high resolution MRI (hrMRI) with indirect cartilage evaluation of MRI inter- bone distance, by evaluating their reliability, and prevalence and agreement of cartilage damage in hand OA patients and healthy controls.
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