The effect of alternate style keyboards on severity of symptoms and functional status of individuals with work related upper extremity disorders

Abstract

There is evidence that performing job tasks involving repetition, vibration, sustained posture or forceful movement may contribute to symptoms of work related upper extremity disorders. Typing is one such activity; symptoms that develop as a result of this activity can affect performance of work, self-care and leisure occupations. Studies investigating the impact of ergonomic keyboards on symptom reduction are limited, and little research exists regarding the reduction of key activation force as an intervention.

Methods: This randomized, prospective study used a sample of 68 symptomatic workers employed by a single company. One group received a commercially available ergonomic keyboard, a second group used a modified version of the same keyboard designed to reduce activation force, vibration and key travel. We measured symptoms and clinical signs, functional status, and device satisfaction in both groups over a six-month study period.

Conclusions: Between-groups analyses indicated that the groups performed similarly on the outcomes of interest. Repeated-measure analysis identified a reduction of symptoms, an improvement in functional status, preference for and increased satisfaction with the intervention keyboards, and maintenance of typing speed and accuracy for both groups.