With nearly seven billion mobile devices in use throughout the world the potential for widespread long term harm to the neck, shoulder, and hands by repeated texting and other keyboard use will be a significant challenge for occupational therapists in this century.
Harcum’s Occupational Therapy Assistant Program Director Dr. Michael Gerg and his colleagues at Temple and Rutgers Universities decided to explore the ergonomic health issues that could arise from the proliferation of handheld devices. It would become his doctorate capstone project in Temple University’s Department of Rehabilitation Sciences in 2013.
Dr. Gerg and his co-researchers David M. Kietrys of the Department of Rehabilitation and Movement Sciences at Rutgers University and Judith Gold of the Center for Musculoskeletal Research at University of Gävle and Temple University’s Department of Public Health wanted to find out how the most active users of such devices are affected. Their initial project, “Running head: Mobile device type effects on posture and muscle activity while texting,” must be seen within with the context of worldwide text messaging frequency expected to increase to 9.4 trillion annually by 2016, up from 5.9 trillion in 2011.
As far as Dr. Gerg and his colleagues are aware, “no previous studies have examined touch screen size and its influence on upper extremity muscle activity, upper trapezius muscle activity, and cervical posture.”
“Case reports and epidemiologic studies indicate there is a potential risk of musculoskeletal symptoms and musculoskeletal disorders (MSDs) in the neck, shoulder, and hands with increased exposure to mobile device use for text messaging,” they found. “Texting on mobile devices requires muscle activity to hold the device and type while texting. The moment generated through key activation (typically by the thumb) must be counterbalanced, likely through activation of the finger flexors and wrist extensors.
Aspects of mobile device design, including input device type (touch screen or physical keypad), device weight, and screen size may influence ergonomic exposures while texting.”
The researchers selected twenty “right hand dominant” Temple University students with experience in mobile device text messaging to perform a text messaging task using four different mobile devices and four text messaging configurations. The mobile devices used in the study were a physical keypad phone, 3.5” touchscreen phone, 7” tablet device, and 9.5” tablet device.
