Positioning of tablet computers important for neck injury prevention
MedWire News: The natural posture of tablet computer users tends to be worse than that of desktop and laptop computer users, putting them at greater risk for neck pain or injury, suggest study findings.
"Compared to typical desktop computing scenarios, the use of media tablet computers is associated with high head and neck flexion postures, and there may be more of a concern for the development of neck and shoulder discomfort," said investigator Jack Dennerlein (Harvard School of Public Health, Boston, Massachusetts, USA) in a press statement.
Dennerlein and team suggest that such problems can be avoided by higher placement of the tablet, for example, on a table rather than on a lap or by use of a specialized case that allows the user to optimize their viewing angle.
Desktop computer screen positioning is known to be important for prevention of neck, back, and shoulder strain. The rapid increase in the number of people using tablet computers has led to concern about the impact of poor user posture on these areas of the body.
To assess the natural posture of tablet users, Dennerlein and colleagues recruited 15 users who were asked to complete four tasks while positioned as they would normally sit when using their tablet while travelling or at home.
The tasks carried out by the participants were chosen to represent "typical" tablet usage and included internet browsing, reading a newspaper article, playing a game of solitaire, and email reading.
The four positions included having the tablet on the user's lap supported by one hand, on the lap supported by the case (15°), on a table at a working angle (45°), and on a table at a movie-watching angle (73°).
Head and neck angles were measured using an infra-red light-emitting diode marker-based motion analysis system.
Denerlein and co-authors report in Work that the head/neck angles of the tablet users taking part in this study were largely greater than the angles reported in previous studies for laptop and desktop computer users. They note that the optimum angle was achieved when the tablet was on the table at a movie watching angle, and the worst when the tablet was supported by the user's hand on their lap.
The investigators also found that postures varied between different tablets and that the greatest amount of variation occurred when in the "lap supported by the case" or the "table at a working angle" scenarios.
"Further studies examining the effects of tablet and configuration on arm and wrist postures are needed to clarify and complete the postural evaluation," commented Dennerlein.
"Our results will be useful for updating ergonomic computing standards and guidelines for tablet computers. These are urgently needed as companies and healthcare providers weigh options to implement wide-scale adoption of tablet computers for business operations," he concluded.
By Helen Albert