A METHOD FOR DEVELOPING BIOMECHANICAL PROFILES OF HAND-INTENSIVE TASKS

Objective. To develop a methodology for generic, comprehensive biomech anical profiling of hand-intensive tasks. Design. Based on a multifact orial model of work-related musculoskeletal disorder development, a me thod was developed for continuous, simultaneous measurement of relevan t variables (wrist and finger joint position, force, muscle activity, and carpal tunnel pressure). Joint dynamics and tendon travel were der ived. Background. Few generic dose-response relationships have been id entified for work-related musculoskeletal disorders. This may improve if methodologies are developed that quantify multiple factors along se veral dimensions (means, cumulative exposure, etc.). This requires con tinuous, simultaneous measurements, and facilitates examination of int eractions. Methods. Five touch-typists were instrumented to quantify t heir biomechanical profiles using the methodology, and to evaluate the sensitivity of the method to various work organization/design conditi ons. Results. The method captured individual and group responses to de sign conditions and revealed interactions and trade-offs between respo nse variables. Carpal tunnel pressure was found to be sensitive to rad ial-ulnar wrist posture. Conclusions. Multi-variable biomechanical pro filing can provide insight into effects of work design on workers; how ever, to achieve statistical significance large numbers of subjects ar e needed.