This week from Dr. Cerami and Utah Sports and Wellness
From: Applied Ergonomics, January 2017 (https://www.sciencedirect.com/science/article/pii/S0003687016301235)
In this study, we look at young adults aged 20-24 years to examine the correlation between texting and musculoskeletal disorders. In the United States, text messaging is the most frequently used type of communicative medium. The physical exposure when texting consists of low physical load, repetitive thumb movements and neck flexion. It is known that neck flexion and highly repetitive movements are considered risk factors for musculoskeletal disorders and for developing pain in neck, shoulder and upper extremities. Associations with neck pain were found at levels of text messaging as low as 6 texts per day.
The aim was to examine whether texting on a mobile phone is a risk factor for musculoskeletal disorders in the neck and upper extremities in a population of young adults. In a longitudinal population-based cohort study with Swedish young adults (aged 20-24 years) data were collected via a web-based questionnaire at baseline (n = 7092) and after one and five years. Cross-sectional associations were found between text messaging and reported ongoing symptoms in neck and upper extremities (odds ratios, ORs 1.3-2.0). Among symptom-free at baseline prospective associations were only found between text messaging and new cases of reported symptoms in the hand/fingers (OR 2.0) at one year follow up. Among those with symptoms at baseline prospective associations were found between text messaging and maintained pain in neck/upper back (OR 1.6). The results imply mostly short-term effects, and to a lesser extent, long-term effects on musculoskeletal disorders in neck and upper extremities.
These authors also note:
- In the subjects with symptoms, almost all individuals had the neck flexed forward and did not support their arms. “This causes static muscular load in the neck and shoulders. Furthermore, they held the phone with one hand and used only one thumb, implying increased repetitive movements in hand and fingers. This distinguished them from the group without symptoms, in which it was more common to sit with a straight neck, to support the forearm, to hold the phone with two hands and to use both thumbs.”
- “Associations were found between text messaging and reported pain in the neck/upper back, shoulder/upper extremities, and numbness/tingling in the hand/fingers for both men and women.”
- “There were clear associations between the highest category of text messaging and pain in the neck/upper back.” [40% increased risk for women, 100% increased risk for men]
- Women have a higher texting velocity and therefore spend less time than men on the same texting task, which may explain their reduced incidence of musculoskeletal problems.
- “It is common to sit with a flexed neck while texting,” and the “head flexion angle was larger when text messaging compared with web browsing and video watching.”
- “Sitting with the head bent forward without supporting the arms causes a static load in the neck and shoulder muscles, which could explain the reported pain from neck/upper back.”
- These authors believe that the associations between cell phone use and health symptoms are underestimated because they did not include data on how much the participants use their mobile phones for other activities, e.g. gaming.