Analysis of neck and shoulder postures, and muscle activities relative to perceived pain during laptop computer use at a low-height table, sofa and bed

Article type: Research Article

Authors: Intolo, Pattariya^{a; *} | Shalokhon, Bunnawat^a | Wongwech, Geerapong^a | Wisiasut, Pushaya^a | Nanthavanij, Suebsak^b | Baxter, David G.^c

Affiliations: [a] Faculty of Physical Therapy, Srinakharinwirot University, Nakhon Nayok, Thailand | [b] Sirindhorn International Institute of Technology, Thammasat University, Bangkok, Thailand | [c] Faculty of Health Sciences, University of Otago, Dunedin, New Zealand

Correspondence: [*] Address for correspondence: Assist Prof. Pattariya Intolo, Department of Physical Therapy, Faculty of Physical Therapy, Srinakharinwirot University, Nakhon Nayok, Thailand, 26120. E-mails: drpattariya@gmail.com, pattariy@g.swu.ac.th.

Abstract: BACKGROUND:Laptop computers are used in various places and situations. The number of laptop users experiencing musculoskeletal disorders (MSDs) has increased drastically due to, in part, inappropriate workstations. OBJECTIVE:To investigate the neck and shoulder postures, and muscle activity relative to perceived pain when using the laptop at a low-height table, sofa, and bed. METHODS:Twenty male participants aged 18–25 years were randomly assigned to perform laptop computer operation at 3 workstations for 10 minutes during which neck and shoulder angles, muscle activity, and pain were recorded by using an Electrogoniometer, Electromyography (EMG), and visual analog scale (VAS), respectively. RESULTS:Neck flexions when working at the sofa (18.6°±12.2°) and bed (17.2°±10.5°) were significantly (p < 0.05) greater than that at the low-height table (7.8°±6.5°). However, shoulder flexion when working at the low-height table (28.2°±13.0°) was significantly (p < 0.05) greater than that at the sofa (13.8°±8.6°) and bed (10.91°±7.8°). Working at the low-height table caused the shoulder flexor muscle activity to be significantly (p < 0.05) higher than working at the sofa and bed. Neck pain was reported during laptop computer use at the sofa and bed, and upper back pain when working at the low-height table. CONCLUSIONS:High neck flexion and pain were found while working at sofa and bed, whereas high muscle activity at shoulder and upper back pain were found while working at the low-height table.

Keywords: Notebook computer, position, electromyography, discomfort, non-desk location

DOI: 10.3233/WOR-192942

Journal: Work, vol. 63, no. 3, pp. 361-367, 2019