Did you know that the average human head weighs 10 pounds in a “neutral position” – where the ears are aligned over the shoulders? Did you know that for every inch you tilt your head forward, the pressure on your spine doubles? In other words, if you are reading this blog with your head leaning down, or slouched over in a chair, you are asking your neck to support 20-30 pounds of weight. Now ask yourself – how many hours per day do you spend hunched over your smart phone, tablet, or some sort of mobile electronic device? Your musculoskeletal system, particularly your neck and arms, may be paying the price for the convenience of having instant and portable access to all that information.
In 2011, Canadian researchers Berolo, Wells and Amick conducted the first epidemiological study to investigate the frequency of upper body musculoskeletal pain of in mobile device users.  This was the first study of this fast-growing health concern to provide empirical evidence of relationships between mobile device use and symptoms of the upper extremity and neck. Participants in the study reported their daily use of mobile devices and self-reported pain symptoms through an internet based questionnaire. 104 students and 32 staff or faculty members participated in the study (80 females, 60 males). 94% were right hand dominant, and 26% use both thumbs to type (vs. one thumb typing)). The study revealed:
- 98% of the study participants used a hand-held mobile device for emailing, scheduling, browsing the internet, making phone calls, watching videos, taking pictures, or gaming.
- Participants used such devices for a mean time of 4.65 hrs/day
- 84% reported at least some pain in at least one body part
- Pain of any severity was reported as follows:
- 68% in the neck
- 62% in the upper back
- 32% in the right elbow and lower arm
- 52% in the right shoulder
- 46% in the left shoulder
- 27% in the left elbow and lower arm
- Statistically significant associations were observed between total time spent using a mobile device and pain in the left shoulder, the right shoulder, and the neck
The study also indicated that musculoskeletal symptoms can also develop in the extremities with activities such as typing, as pain in the hands was a common complaint, particularly at the base of the thumbs. This would be consistent with case reports suggesting a link between device use and both tenosynovitis and osteoarthritis  at the base of the thumb (carpometacarpal joint), as well laboratory studies showing that smaller keyboards (as compared to desktop or laptop computers) may increase “static strain” on the hand and arm muscles.
While mobile electronic devices have become an indispensable part of life for many people, the Berolo Study underscores the importance of taking simple steps to limit the amount of time we place our bodies in an abnormal position that can increase stress on the muscles, cause fatigue, muscle spasms and even stress headaches. These include improving posture, raising electronic devices towards the head (not vice-versa), taking breaks to break up static body positions, and using speech-to-text functions rather than typing.
Individuals already suffering from musculoskeletal injury due to trauma may be at a higher risk for complications arising from the over-use of personal electronics. Postural strain, overuse, or prolonged immobilization in these patients can result in additional changes in posture or body mechanics that may bring about spinal alignment problems and muscle shortening. As such, patients recovering from traumatic injury to neck, back, arms, or hands should be particularly aware of their habits while texting or surfing the web on their electronic tablets to prevent additional injury or a prolonged recovery.