Automatic joint detection in rheumatoid arthritis hand radiographs

The measurement of joint space width (JSW) in hand x-ray images of patients suffering from Rheumatoid Arthritis (RA) is a time consuming task for radiologists. Manual assessment lacks accuracy and is observer-dependent, which hinders an accurate evaluation of joint degeneration in early diagnosis and follow-up studies. Automatic analysis of the JSW is crucial with regard to standardization, sensitivity, and reproducibility. In this paper, we focus on both joint location and joint margin detection. For the evaluation, five hand radiographs from RA patients, in which the joints have been manually delineated, are used. All finger joints are located correctly with margins differing 0.1 mm on average from the manual delineation.