91 Assessment of trapezius muscle parameters among sitting and standing workers

Abstract

Objectives Longlasting sitting position has often been associated with the discomfort and/or pain in neck-shoulder region. The objective of this study was to examine the trapezius muscle parameters among sitting and standing workers and to investigate which is more overreaching to trapezius muscle. Methods A total of 42 female workers in two different companies were recruited in this study. There were 21 workers (sitting workers) who were sitting at the computer most of the working day and 21 (standing workers) who were standing at their workstation and assembling the products. Trapezius muscle mechanical charecteritics were measured by myotonometry, which calculates objective parameters on state of muscle mechanical properties (frequency which characterising tone, decrement which characterising elasticity and stiffness). The upper trapezius muscle was measured at resting position in seated, both on the left and right side. Also the visual analogue scale (VAS) was used to assess the intensity of pain in neck and shoulder region. The differences between two groups were assessed with indenpendent group T-test. Results The mean neck and shoulder pain VAS score among standing workers was 1.79 (SD 2.36) and 1.36 (SD 2.35) and among sitting workers 2.40 (SD 2.75) and 2.17 (SD 2.52) respectively. The measured outcomes showed that frequency in the right side was 15.5% and in the left side 14.9% higher among sitting workers. Stiffness was also higher among sitting workers respectively 22.6% and 25.5%. Trapezius muscle frequency and stiffness were also statistically higher in sitting workers (t-test p ≤ 0.001) and in both body sites. There were no differences in decrement. Conclusions The result showed that sitting work induces higher tone and stiffness in upper trapezius muscle than standing work. Considering that the ergonomic workplace reorganisation should be done.