Evaluation of Contact Pressure and Biomechanical Exposures on Different Work Surface Hardness

Contact pressure has been identified as a risk factor for musculoskeletal disorders (MSDs) in various occupational settings. Given that contact pressure over the palmar aspect of the wrists may increase risks for MSDs, the present study was designed to determine whether a work surface with a soft leading edge could reduce contact pressure and subjective musculoskeletal discomfort without affecting task performance during a series of standardized computer work tasks. Using a repeated-measures blinded experimental design with eighteen subjects, during the performance of a series of standardized computer work tasks, contact pressure, computer work performance and perceived fatigue in the upper extremities were evaluated and compared between a conventional hard-edge and soft-edge work surface. The results found that contact pressure and perceived fatigue in the wrists were lower on the soft-edge work surface compared to the conventional hard-edged work surface (p’s < 0.03), whereas no differences were found in computer task performance between the two work surfaces. The study findings showed that soft-edge work surface reduced contact pressure in the wrists and the reduction in contact stress may reduce the risks for developing work-related MSDs when working at the computer.

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