The comparison of magnetic resonance imaging and radiographs to assess structural progression over 5 years in hand osteoarthritis.

Objective: . The aim was to explore the agreement between 1.0 T MRI and conventional radiography (CR) to detect progression of hand OA over 5 years and the associations between structural progression and incident joint tenderness.

Methods: Paired radiographs and paired MRIs of the second-fifth IP joints of the dominant hand from 69 hand OA patients were read for osteophytes, joint space narrowing and erosions. Patients with two or more joints demonstrating progression of any structural feature(s) were classified as progressors per imaging modality. Agreement between methods to detect progressors was evaluated with κ and intraclass correlation coefficients. At the joint level, the associations between methods to detect progression were explored with generalized estimating equations. Likewise, we analysed the associations between progression per imaging modality and incident pain.

Results: MRI (58.0%) and CR (62.3%) detected similar numbers of progressors. The agreement between methods to detect progressors was good (κ = 0.61). We found good agreement between methods regarding the number of progressive joints (intraclass correlation coefficient = 0.61, 95% CI: 0.43, 0.76). At the joint level, MRI progression was associated with radiographic progression (P < 0.001). Incident joint tenderness was more common in joints with progression by MRI and CR, but statistically significance was not reached.

Conclusion: Both 1.0 T MRI and CR detect a similar amount of progression over 5 years in patients with hand OA, although not in exactly the same joints. As CR assesses more joints for a lower cost, CR should be the imaging modality of choice rather than 1.0 T MRI in observational studies with a long period of follow-up.