RESUMEN
The primary aim of the study was to detect the MRI changes in hand and foot in patients with early rheumatoid arthritis [RA] who had normal conventional radiography of both hands and feet. The secondary aim was to detect any correlation between the MRI changes and the disease activity score with three variables [DAS-3]. Thirty adult patients with early RA, fulfilling the 1987 revised American College of Rheumatology [ACR] criteria for the classification of RA, with disease duration between 2-6 months were recruited in the study. All patients underwent a full history taking and thorough rheumatological examination. Disease activity score with three variables [DAS-3], including the Ritchie articular index [RAI], swollen joint count [SJC] and ESR, was calculated to every patient. Routine laboratory investigations were done. Normal conventional radiography of hands and feet was an inclusion criterion. MRI to the clinically dominant hand and foot was done to every patient. 29 patients [96.7%] had MRI changes consistent with the inflammation and destruction. MRI changes were found in 66.7% of patients in hand and foot, in 20% in foot and in 10% in hand. SJC and ESR were statistically elevated in patients with MRI changes in hand and foot, in comparison with those with either hand or foot. The detected MRI changes were synovitis in 93.3%, erosions in 60%, bone marrow edema in 83.3%, tenosynovitis in 76.7% and foot bursitis in 66.7% of patients. According to the anatomical distribution, synovitis was detected in wrist joint in 76.7%, in MCP joints in 70%, in hindfoot joints in 60% and in MTP joints in 83.3% of patients. Erosions in wrist were detected in 40%, in MCP in 43.3%, in hindfoot in 36.7% and in MTP in 40% of patients. Bone marrow edema which is a unique MRI finding was detected in wrist in 66.7%, in MCP in 60%, in both hindfoot and MTP in 70% for each of patients. Tenosynovitis was detected in hand in 60% and in foot in 66.7% of patients. MRI hand and foot is an important imaging modality. It detected the pathologic manifestations at the early stages of RA especially the bone marrow edema that contains information about initial inflammatory activity and the potential for erosion development. Early disclosure of these pathological findings by MRI helps in initiating early aggressive therapy to keep the functional outcome. No correlation was found between the DAS-3 and MRI findings except the ESR which was statistically elevated in patients with erosion. This reinforced the importance of MRI in early RA. Also, MRI foot is important in early RA being involved alone in fifth of our patients