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Published on: October 5, 2020
Differences in Upper Extremity Muscle Activity, Neck Angle, and Body Discomfort Between Tablet Usage With Virtual
Praphatson Sengsoon1,2, Kanruethai Threesittidath1,2, Thunyaporn Singhadacha1
1Department of Physical Therapy, School of Allied Health Sciences, Walailak University, Nakhon Si Thammarat, Thailand.
Background:
The objective was to compare the differences in muscle activity of the upper extremities, neck angles, and body discomfort during tablet use between virtual and Bluetooth keyboards.
Methods:
Twenty-four female volunteers were randomly assigned to use a tablet with keyboard for typing articles. The first order was randomly selected for 30 min, with a 30-minute break before the next keyboard layout test began.
Results:
The result showed a statistically significant difference in the muscle activity of the upper trapezius while using a tablet between the two types of keyboards (p < 0.001). In addition, there were statistically significant differences in muscle activities of the upper trapezius (p < 0.05), extensor digitorum communis (EDC) (p < 0.001), and flexor digitorum superficialis (p < 0.001), craniohorizontal angle (p < 0.001) and craniovertebral angle (p < 0.001), and body discomfort in the neck and shoulder areas before and after using the tablet with each keyboard (p < 0.05).
Conclusion:
Tablet use with the two types of keyboards induced an increase in muscle activity, neck flexion angles, and body discomfort, which may contribute to the occurrence of musculoskeletal disorders (MSDs). This study may serve as a basis for developing guidelines to reduce the risk of MSDs during tablet use.

