Willey Marc S
Department of Occupational Therapy, University of Central Arkansas, 201 Donaghey Avenue, Conway, AR 72035, USA. Tel.: +1 501 450 5569; Fax: +1 501 450 3622; E-mail:
Work. 2011;39(4):441-4. doi: 10.3233/WOR-2011-1193.
Extensive keyboarding has been associated as a risk factor for repetitive strain injuries. Modifying the slope angle may decrease the negative cumulative effects of this activity.
This study investigated the kinematic effect of four keyboard modifications on wrist extension during keyboarding.
32 female college students between the age of 21 and 25, mean age of 22.4 years.
A Greenleaf Biomechanical Analyzer was utilized to determine the wrist extension angles across four keyboard modifications.
A one way ANOVA with repeated measures revealed significant differences between all 4 test conditions for both right and left wrist extension, Wilks Lambda 0.249 F (3,29) 29.1, p=0.000 n2 = 0.75 for left wrist and Wilks Lambda 0.158 F (3,29) 51.6, p=0.000 n2 = 0.84 for the right wrist.
The study suggests that simple modifications to a standard computer keyboard can significantly vary wrist angles during keyboarding. These findings could possibly improve worksite modification guidelines and prevent repetitive strain injuries among keyboarders.