The accuracy of magnetic resonance imaging of the hands and feet in the diagnosis of early rheumatoid arthritis

ObjectiveTo analyze MRI findings of early RA in the hand and foot joints and to determine any discrepancies between MRI findings in the hands and feet.MethodsTwenty one patients who fulfilled the 1987 American College of Rheumatology (ACR) criteria for the diagnosis of RA at the onset underwent MRI of both hands and feet.ResultsIn 18 out of 21 patients, rheumatoid changes were observed in the hand and foot joints. However, rheumatoid changes were observed only in the hand joints of the three remaining patients. MRI revealed pathologic findings suggested RA in the hands of 21 of 21 patients. In the feet, MRI findings suggested RA in 18 of 21 patients. Bone erosions were seen in the hands of 14 patients (67%). Observers found as many bony changes in the hands as in the foot joints. MRI detected active synovitis in 17 patients (81%) in the hands and in 15 patients (71%) in the feet. MRI findings suggested bone edema in the hand and foot joints in 14 (63%) and 11 patients (52%), respectively. There was no significant difference between the MCP and MTP joints with respect to RA-based changes obtained in the MRI (p > 0.05).ConclusionEvidence of foot involvement is a frequent occurrence in early RA.