Application of ImageJ Software for the Quantification of Hand Joint Space Narrowing in Patients with Rheumatoid Arthritis.

Background: ImageJ software is used to quantify the joint space width (JSW) of hand and wrist in patients with rheumatoid arthritis (RA) as well as in the healthy control group.

Methods: Forty-one RA patients and 31 healthy controls were included in this study. All of 72 participants underwent digital radiography of the bilateral hand and wrist; then, all the images were opened by ImageJ software to measure the width of wrist and hand joint space (total 2160 joints). Joint space narrowing (JSN) was defined if the width was less than the mean - 2SD of the control group.

Result: The mean JSW of all sites of wrist and hand joints of RA patients were significantly reduced as compared to those in the control group (p<0.001). There were 37/41 (90.24%) RA patients who had JSN in at least one joint in hand or wrist. In total, 70.89% of joints on the right and 68.46% of joints on the left wrist and hand had JSN.

Conclusion: ImageJ software is simple and convenient that helps rheumatologists quantify the width of joint space for diagnosis and follow-up in RA patients.