Objective: To assess the longitudinal reliability of the Outcome Measures in Rheumatology (OMERACT) Thumb base Osteoarthritis Magnetic resonance imaging (MRI) Scoring system (TOMS).
Methods: Paired MRI of patients with hand osteoarthritis were scored in 2 exercises (6-mo and 2-yr followup) for synovitis, subchondral bone defects (SBD), osteophytes, cartilage assessment, bone marrow lesions (BML), and subluxation. Interreader reliability of delta scores was assessed.
Results: Little change occurred. Average-measure intraclass correlation coefficients were good-excellent (≥ 0.71), except synovitis (0.55-0.83) and carpometacarpal-1 osteophytes/cartilage assessment (0.47/0.39). Percentage exact/close agreement was 52-92%/68-100%, except BML in 2 years (28%/64-76%). Smallest detectable change was below the scoring increment, except in SBD and BML.
Conclusion: TOMS longitudinal reliability was moderate-good. Limited change hampered assessment.
Keywords: HAND; MAGNETIC RESONANCE IMAGING; OMERACT; OSTEOARTHRITIS; OUTCOMES RESEARCH; THUMB BASE.