Development of an Ergonomic Writing Assistive Device for Finger Pain Reduction in the Elderly

Abstract

The decreased muscle mass and increased prevalence of musculoskeletal diseases in the elderly means that this population often experiences difficulty with writing. Although various commercial writing assistive devices exist to reduce pain and improve writing efficiency, low satisfaction with their design prevents them from being widely adopted. In this study, we developed a new ergonomic writing assistive device that overcomes these shortcomings and reduces finger pain. Twenty elderly people with normal writing skills participated in a performance evaluation of our designed device. We used two commercial writing assistive devices and the developed writing assistive device to write a given experimental sentence three times each for each device. For each device, finger-related muscles activity and finger pressure were measured during the experiment, and satisfaction level was evaluated using the modified QUEST 2.0 after the experiment. As a result, the activity in abductor pollicis brevis (18.16%) and first dorsal interosseous muscle (14.17%) was significantly higher when using the NDWAD (newly developed writing assistive device) than when using commercialized WADs (writing assistive devices) (p < 0.05). Finger pressure in the thumb (0.59 N), index finger (1.09 N), and middle finger (0.46 N) was significantly lower when using NDWAD than when using WADs (p < 0.05). The satisfaction level of NDWAD (4.47) was higher than that of WADs. Therefore, we confirmed that our design reduced finger pressure and improved user satisfaction. Consequently, the NDWAD developed in this study can be used as a writing aid not only for the elderly, but also for patients with writing disabilities.