طب کار (May 2016)
Assessing Typists Office Workstations from Occupational Biomechanics\' Point of View
Abstract
Introduction: Appropriate office workstation design and adjusted keyboard slope could prevent upper extremity musculoskeletal disorders caused by CTDs. The purpose of this study was to compare wrist and finger motion angles during typing in different workstations with different keyboard slopes. Methods: In this experimental study, 10 female typists of university workers were chosen randomly. Test was performed on two different adjustable and non-adjustable chairs with four different keyboard slopes including 15, 7, 0, -7 degrees. Wrist and fingers kinematic data were calculated by Vicon motion analysis system and MATLAB software. Results: Average wrist flexion angles were significantly different in different keyboard slopes. In adjustable workstation, the lowest mean value of maximum, average, min mum of flexion was measured for keyboard whose slope was adjusted to 15 degrees. The lowest mean for observed flexion in the metacarpophalangeal joints in the second and fifth fingers was measured in workstation with adjustable seats and keyboard whose slope was adjusted to 15 degrees. In the proximal interphalangeal joint of the second finger, the lowest mean was obtained in the workplace with adjustable seats and the keyboard whose slope was adjusted to 15 degrees. Conclusion: During typing on keyboard, as much as the finger joint angles are close to zero degree, less stress is put on the joints. In this study, the lowest means for the degrees of joint flexion were observed in the workstations with adjustable seats and the keyboard with 15-degree slope.
