Page 67 - Imaging of Osteoarthritis and Rheumatoid Arthritis in Hand Joints

Accuracy of cartilage MRI of CMC1; comparison with histology
Introduction
Osteoarthritis (OA) of the hand is the most prevalent disease of the hand joint,
which can lead to pain and functional impairment. The disease is characterised
by cartilage loss, subchondral bone changes and inflammation of the synovium.
Despite the fact that only changes of bone are directly visible on conventional radiography (CR), and that joint damage on CR is only weakly associated with symptoms,1 it is the most widely used imaging method for assessing structural
changes in hand OA in both clinical practice and clinical trials.2, 3 Magnetic
resonance imaging (MRI) is gaining popularity in hand OA studies4, 5 as it
depicts bone, cartilage, and soft tissue changes, and images the complete joint
in multiple planes. As a result, MRI has given us new insights into hand OA such
as the involvement of collateral ligaments,6, 7 the high prevalence of synovitis,8 4 and significant associations of joint pain with bone marrow lesions (BML) and
synovitis. 9, 10
MRI of cartilage in hand OA has yet been less well-explored, yet accurate cartilage assessment would be a valuable addition to other pathological change detected by MRI in the assessment and follow-up of the whole joint in hand OA. In studies of knee OA, quantification of cartilage using MRI is often an outcome measure in clinical trials, but cartilage imaging in the small joints of the hand is more challenging, as smaller voxel sizes are needed to depict the thin cartilage layer. Previous studies have reported that reliable quantitative evaluation of the cartilage layer in the small joints of the hand can be performed using conventional MRI and small dedicated coils.11, 12 While in-vivo cartilage quantification with MRI in knee OA correlates well with histological findings,13, 14 to our knowledge, there are no reports in the literature of a comparison between in-vivo MRI cartilage assessment of hand joints and histology. As surgery in hand OA is only regularly performed for treatment of thumb base OA, comparison between MRI and histology is only feasible in patients with symptomatic thumb base OA.
The aim of this study was therefore to quantitatively compare MRI-detected cartilage loss in patients with OA in the first carpometacarpal (CMC1) joint with histology.
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