Nikoo Asadi - PhD Student in Biomechanics, Islamic Engineering, Islamic Azad University, Tehran Branch, South Iran

Target: The aim of this paper was to investigate the effect of rheumatoid arthritis on the kinematics in grasping objects Background: In ۲۰۲۰, Inflammation from inflammatory arthritis types such as rheumatoid and psoriatic arthritis can cause weakness in the grip, says John Esdaile, MD, MPH, rheumatologist and the scientific director of Arthritis Research Canada. Osteoarthritis can also cause inflammation in your hand from the breakdown of cartilage, he says. Arthritis also changes your grip functionally. Swollen, painful joints are simply harder to use Arthritis in the hands changes your grip from a structural perspective. Arthritis in the fingers and thumbs is incredibly common and it always affects your grip because ۵۰ percent of hand use — and ۱۰۰ percent of gripping — requires a functioning thumb and says A. Lee Osterman, MD, a professor of hand and orthopedic surgery at Thomas Jefferson University and president of the Philadelphia Hand Center.Materials and Methods:In this study, a subject with ۸۱-year-old rheumatoid arthritis, height ۱۶۰ cm, weight ۵۸ kg and female gender with a history of rheumatoid arthritis for ۶ months was studied. In this study, using video imaging with a frequency of ۱۰۰ Hz and a resolution of ۱۰۸۰ pixels and marking on the joints of the right hand and using image processing software Tracker motion image processing was processed.Spatiotemporal spatial position of each marker was determined using scaling methods and the lengths, angles and range of motion of the studied members and joints were determined and analyzed using the relationships of spatial geometry. Results: Based on this study, it was found that the effect of damage rheumatoid arthritis to the fingers of the right hand on the range of motion of the joints of the right index finger and middle finger caused more changes than normal and caused limited movement.Conclusion: This complication causes the patient to have pain in the joints of the right finger and middle finger and a decrease in movement speed in general, which indicates the existence of problems related to limited movement in these joints. These patients also have problem to get objects by their fingers.