Till now, Rheumatoid Arthritis Magnetic Resonance Imaging Score (RAMRIS) has been authenticated for use in the metacarpophalangeal (MCP) and wrist joints, but not in metatarsophalangeal (MTP) joints. The outcomes of this study provide encouraging results regarding the use of scoring systems for MTP joints in trials in early phases of rheumatoid arthritis (RA). A good to excellent intra- and interreader reliability for status and change scores was observed, with special reference to a  > 0.90 score of ICC for the inflammatory features.

The reliability of the RAMRIS for metatarsophalangeal (MTP 1–5) joints has been explored in this study.

The patients with clinically confirmed arthritis and symptom duration < 2 years who were naive to DMARD underwent 1.5 Tesla MRI of MTP, metacarpophalangeal (MCP 2–5), and the wrist joints. The bone marrow edema (BME), synovitis, tenosynovitis, and erosions (MRI outcomes) were studied.

The following flowchart of patient selection has been portrayed in below figure:

The Bland-Altman (BA) plots, intraclass correlation coefficients (ICC), and smallest detectable change (SDC) were all noted. A comparison of MRI data of MTP joints was done with wrist and MCP joints.

In early arthritis, the interreader ICC and mean scores were BME ICC 0.91–0.92, erosions 0.88–0.89 and tenosynovitis 0.80–0.8. These coefficients were similar in patients with clinically suspicious arthralgia.

The intrareader ICC for inflammatory MRI characteristics were 0.84–0.98, for erosions 0.71 and 0.92 (2 readers). Change score ICC ≥ 0.90 was observed. As per BA, there was low systematic bias. Similar reliability scores of MTP joints were found to that of the wrist and MCP joints.

The RAMRIS can be used to reliably evaluate the status and variation of MRI outcomes.