A quantitative description of typing biomechanics.

One approach to combating work- related upper extremity musculoskeletal disorders (UEMSDs) is to improve understanding of MSD risk factors through quantitative biomechanical characterization of manual tasks, including joint postures, joint dynamics, and force exertion. This paper describes a methodology employed to quantitatively assess professional typing in a workplace setting, and the results of that assessment. Results are compared between different kinds of typing tasks, and between typing and hand- intensive industrial tasks, based on nontask- specific biomechanical terms. Quantitative, biomechanical characterizations of manual tasks will lead to identification of appropriate ranges for joint kinematics and force exertion, which will, in turn, facilitate proper design of manual tasks. Additionally, the methodology could be used to assess manual performance of skilled tasks for proper (healthy) technique, or be used to evaluate progress through a course of rehabilitation (when do an impaired worker's motions begin to resemble motions of healthy workers?).