Changes in cervical range of motion, flexion-relaxation ratio and pain with visual display terminal work

BACKGROUND: The static posture in visual display terminal (VDT) workers results in increased forward neck flexion and increased static muscle tension in the neck and shoulder regions. However, few studies have objectively quantified the change in head posture induced shoulder pain during VDT work. OBJECTIVE: This study elucidated changes in pressure pain in the upper trapezius muscles, cervical ROM, and the cervical flexion-relaxation ratio after continuous long-term VDT work. PARTICIPANTS: Twelve young VDT workers were recruited. METHODS: The pressure pain of the upper trapezius muscles, active CROM, and cervical flexion-relaxation ratio were measured in all subjects once before and once after VDT work. RESULTS: The pressure pain threshold of the right upper trapezius muscle was 6.9 +/- 1.6 1b before VDT work and 6.1 +/- 1.0 1b after VDT work, revealing a significant increase with VDT work. The cervical extension, left and right lateral flexion, and left rotation measurers decreased significantly with VDT work. CONCLUSIONS: We postulate that even short-term VDT work has the potential to cause problems. It is necessary to develop a CROM self-measuring device and to monitor patients' musculoskeletal changes frequently.