Identification of wrist and metacarpophalangeal joint erosions using a portable magnetic resonance imaging system compared to conventional radiographs

Abstract

Objective: To compare magnetic resonance (MR) images obtained using a portable MR system to radiographs for identifying bone erosions in the wrists and metacarpophalangeal (MCP) joints of patients with inflammatory arthropathy.

Methods: MR imaging and radiographs were performed in wrists (n = 227) and 2nd and 3rd MCP (n = 188) of 132 patients with inflammatory arthritis to identify erosions. MR imaging was performed using a portable MR system. Findings per body location and per patient were calculated and compared. Additionally, intraobserver and interobserver reliabilities were calculated.

Results: MR imaging identified bony erosions in 125 (95%) patients and in 315 (78%) body locations. By comparison, radiographs identified erosions in 78 (59%; p < 0.05) patients and in 156 (39%; p < 0.05) body locations. Intraobserver reliability (K = 0.564) and interobserver reliability (K = 0.429) exhibited moderate agreement, with reader agreement in 80% of the joints scored.

Conclusion: There was superior sensitivity to bone damage using the portable MR system compared to radiographs of the wrists and MCP joints, suggesting that this scanner is extremely promising for assessment of inflammatory arthritis.