A study of musculoskeletal problems among video display terminal (VDT) users was conducted. The influence of the workstation design was also investigated. The cohort consisted of 539 data entry VDT users employed for at least 3 months by two state governmental agencies. Approximately 90% of the subjects were Caucasian females and the mean age of the cohort was 35.9 years. The subjects completed a questionnaire package to obtain information on biodemographic characteristics and musculoskeletal symptoms. A subsample of 40 data entry VDT users was selected for a more detailed study. Nineteen ergonomic variables related to the workstation thought to influence lower and upper extremity, back and neck, buttocks, leg, and trunk discomfort were objectively rated. Almost constant low back discomfort, followed by neck, buttocks, and right shoulder discomfort were the most frequently reported musculoskeletal symptoms, being reported by 33, 27, 27, and 15% of the subjects, respectively. The frequency of chronic discomfort in the upper extremities on the right side was almost twice that of the left upper extremities. Age, height, body mass, hours of VDT use, and length of employment as a VDT data entry operator were associated with leg, buttocks, trunk, and left and right arm discomfort; however, none of the associations were statistically significant. Chair type, popliteal height minus seat pan height (ph- sph), and (ph-sph) times pan compression were significantly associated with leg discomfort. Seated posture and relative seat back height were significantly associated with trunk discomfort. Relative keyboard height and relative document distance were significantly associated with left arm discomfort. Upper arm angle, relative keyboard height, and right hand extension were significantly associated with right arm discomfort.
Steven L. Sauter, Division of Biomedical and Behavioral Science, National Institute for Occupational Safety and Health, 4676 Columbia Parkway, Cincinnati, OH 45226