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To D.1, Atkinson S.2, Szeto G.3
1Hong Kong Polytechnic University, Rehabilitation Sciences, Kowloon, Hong Kong, 2University of Nottingham, School of Mechanical, Materials and Manufacturing Engineering, Nottingham, United Kingdom, 3The Hong Kong Polytechnic University, Rehabilitation Sciences, Hong Kong, Hong Kong
Background: Work-related neck and upper limb musculoskeletal disorders (WRNULD) are a common problem in office workers. Past research has demonstrated altered motor control with increased neck-shoulder muscle activity and increased neck flexion posture being consistently observed phenomena in those with chronic neck pain. These research studies have mainly been conducted in the laboratory setting, and it is not known whether such postural deviations were actually adopted in the real-time office setting.
Purpose: This study aimed to examine the real-time postures and movements in the cervical and thoracic spine when office workers performed their work and used their mobile phones. Physiotherapists need to understand about people's mal-adaptive postures at the workplace so they can design effective interventions for these problems.
Methods: Twenty female office workers were recruited by convenience sampling to participate in this study within four local offices. Ten of them had a history of chronic neck-shoulder pain and were classified as the symptomatic group (SG) while the rest had no history of such pain and were named the asymptomatic group (ASG). Their mean age (SD) were 43.8 (6.1) years and 36.3 (10.1) years respectively. Inertial motion sensors were placed firmly on a subjects
(1) occipital protuberance,
(2) sixth cervical spinous process,
(3) third thoracic spinous process,
(4) twelfth thoracic spinous process, T12, and
(5) the sacrum.
Spinal angular displacements, namely the upper cervical (UCx), lower cervical (LCx), thoracic (Tx) and lumbar (Lx) were deduced from the relative orientation between sensors. Each participant would wear the sensors for 3 hours while they continued their usual office work including use of desktop computers and use of their smartphones. All the kinematics signals were captured in a data-logger worn on a waist belt.
Results: Generally, subjects in both groups showed the typical flexion posture in the cervical, thoracic and lumbar spine during smartphone compared to non-smartphone tasks. The greatest mean difference was in the upper cervical region which was statistically significant differences between the SG and ASG (p 0.01). Upper cervical and lumbar flexion postures also appeared to be more static in smartphone tasks (p = 0.01 0.02). When the kinematics data were examined in relation to the specific tasks performed on the smartphone, it was found that there were statistically significant differences between groups in UCx mean angles during texting, browsing and multimedia tasks (p 0.01). The results also showed that symptomatic subjects maintained a longer duration of static posture than asymptomatic group in texting task.
Conclusion(s): The present results produced objective kinematics data to confirm the clinically observed postures in people with chronic neck pain. The data confirmed that symptomatic persons maintained a higher degree of cervical flexion posture especially when using smartphones, and this posture was sustained for longer durations compared to the asymptomatic group.
Implications: Physiotherapists should educate their patients on improving their head-neck posture not only in the clinical setting. It is very important to develop interventions that can enhance this postural correction in the workplace.
Funding acknowledgements: Nil
Topic: Occupational health & ergonomics
Ethics approval: This study has been approved by the Human Ethics Committee of the Hong Kong Polytechnic University.
All authors, affiliations and abstracts have been published as submitted.
