Design of an electronic instrumentation for measuring repetitive hand movements during computer use to help prevent work related upper extremity disorder

Repetitive movements for computer users can result in complaints caused by extreme hand posture, finger movements, and force when using the computer, which is known as Work Related Upper Extremity Disorder (WRUED). This study is about the construction of electronic instrumentation for monitoring and quantifying these movements and forces, using sensors to register wrist posture and fingertip force with software developed to collect and process the data. Tests evaluated the performance of the instrumentation with seventeen subjects participating in this study. The maximum extension observed for the first test was 41°, however after training the subject decreased this value to 33°. Six subjects had a wrist extension of between 15° and 41° for the first test; five reduced their wrist extension (between 3° and 33°) during the second test (p = 0.08) while one subject increased instead of decreased it. No subject performed fingertip force greater than 0.77N during the first test; this was reduced to 0.57N during the second test (p = 0.04). The average typing frequency in the group decreased from 3.2Hz to 2.5Hz during the second test (p = 0.01). Results confirm that this solution may potentially contribute to hand movement reeducation, thereby reducing the risk of WRUED for computer users.Relevance to industryKnowledge of repetitive movements during computer use and associated WRUED is essential for prevention. This electronic instrumentation aids the correction of hand movements, which reduces the risk of injury due to inappropriate posture, extreme range of movement, or force during computer use.