Trapezius muscle motor unit activity in symptomatic participants during finger tapping using properly and improperly adjusted desks.

Work-related musculoskeletal disorders in the neck-shoulder area and upper extremities are common among computer users, especially women. We compared temporal changes of motor unit (MU) activation in the trapezius muscle during finger tapping using both appropriate and inappropriate ergonomic desk adjustments. Sixteen intensive and nonintensive computer users with either moderate or severe musculoskeletal disorders participated in the study.