Teenagers glued to their screens for more than three hours a day suffer worse back pain, a new study has revealed.
Girls suffer worse than boys, and back pain is also associated with physical inactivity and low academic achievement.
The nearness of the screen to the eyes as well as sitting or lying on your stomach while viewing were also risk factors, along with the duration.
The team at São Paulo Research Foundation (FAPESP) in Brazil analyzed data from more than 1,600 school pupils aged 13-18.
The first author of the study Dr. Alberto de Vitta, said: "Thanks to the popularization of smartphones and tablets, and the multiplication of video channels, computer games and educational apps, children and adolescents are spending more and more time looking at screens, usually with bad posture, which can cause back pain, among other problems."
Their study focused on the pain from the bottom of the neck into the shoulder blades, known as thoracic spine pain (TSP).
Dr. de Vitta added: "Cell phone mobile use duration of or more than three hours, tablet use time of or more than three hours and semi-lying prone position while using the cell phone and these were also significant predictors of TSP episodes."
Information on risk factors for TSP in high school students is important because children and adolescents with back pain are more inactive, achieve less academically and have more psychosocial problems.
They analyzed data from surveys of 14 to 18-year-old male and female students in the first and second years of high school in Bauru, a medium-sized city in São Paulo state.
Published in the journal Healthcare, the study questionnaire was completed by 1,628 participants of whom 1,393 completed a follow-up questionnaire the following year.
The analysis showed a one-year prevalence of 38.4% (the proportion reporting TSP in both the baseline and follow-up surveys) and a one-year incidence of 10.1% (new TSP reported only in the follow-up survey).
More girls than boys reported TSP, which is common in different age groups of the general population worldwide.
Its prevalence ranges from 15%-35% in adults and 13%-35% in children and teens.
During COVID-19 there was an explosion in screen use exacerbating the cases of TSP and its risk factors which are physical, physiological, psychological and behavioral.
There is also strong evidence of the effects of physical activity, sedentary habits and mental disorders on spinal health.
Dr. de Vitta added: “The study can be used to inform health education programs for school students, teachers, staff and parents.
"The present longitudinal study in Brazil identified a high prevalence and incidence of TSP in high school students.
"Moreover, the TSP is associated with the female sex, mental health problems and body posture while using cell phones, tablets and PCs as well as with the duration of use of cell phones and tablets.
"These variables are mostly modifiable risk factors and amenable to early intervention."