Frequent computer-related activities are an independent risk factor for NSP and LBP. Daily use of computers exceeding 2-3 h seems to be a threshold for NSP and exceeding 5 h for LBP. Computer-related activities may explain the increase of NSP and LBP in the 1990s and the beginning of 2000.

The first aim for this paper was to examine gender and age differences in the intensity of usage of information and communication technology (ICT: computer for digital playing, writing and e‐mailing and communication, and Internet surfing, and mobile phone). Second, we modelled the possible mediating role of sleeping habits and waking‐time tiredness in the association between ICT usage and perceived health (health complaints, musculoskeletal symptoms, health status). The participants were 7292 Finns aged 12, 14, 16 and 18 years responding to a postal enquiry (response rate 70%). The results showed that boys played digital games and used Internet more often than girls, whose mobile phone usage was more intensive. Structural equation model analyses substantiated the mediating hypothesis: intensive ICT‐usage was associated with poor perceived health particularly or only when it negatively affected sleeping habits, which in turn was associated with increased waking‐time tiredness. The associations were gender‐specific especially among older adolescents (16‐ and 18‐year olds). Intensive computer usage forms a risk for boys’, and intensive mobile phone usage for girls’ perceived health through the mediating links. Girls were vulnerable to the negative consequences of intensive mobile phone usage, as it associated with perceived health complaints and musculoskeletal symptoms both directly and through deteriorated sleep and increased waking‐time tiredness. The results of gender‐specific ICT usage and vulnerability are discussed as reflecting gendered psychophysiological, psychological and social developmental demands.

BackgroundMusculoskeletal symptoms among adolescents are related to the time spent using a computer, but little is known about the seriousness of the symptoms or how much they affect everyday life. The purpose of the present study was to examine the intensity of musculoskeletal pain and level of inconvenience to everyday life, in relation to time spent using a computer.MethodsIn a survey, 436 school children (12 to 13 and 15 to 16 years of age), answered a questionnaire on musculoskeletal and computer-associated musculoskeletal symptoms in neck-shoulder, low back, head, eyes, hands, and fingers or wrists. Pain intensity (computer-associated symptoms) and inconvenience to everyday life (musculoskeletal symptoms) were measured using a visual analogue scale. Based on the frequency and intensity, three categories were formed to classify pain at each anatomic site: none, mild, and moderate/severe. The association with time spent using the computer was analyzed by multinomial logistic regression.ResultsModerate/severe pain intensity was most often reported in the neck-shoulders (21%); head (20%); and eyes (14%); and moderate/severe inconvenience to everyday life was most often reported due to head (29%), neck-shoulders (21%), and low back (16%) pain. Compared with those using the computer less than 3.6 hours/week, computer use of ≥ 14 hours/week, was associated with moderate/severe increase in computer-associated musculoskeletal pain at all anatomic sites (odds ratio [OR] = 2.9-4.4), and moderate/severe inconvenience to everyday life due to low back (OR = 2.5) and head (OR = 2.0) pain.ConclusionsMusculoskeletal symptoms causing moderate/severe pain and inconvenience to everyday life are common among adolescent computer users. Daily computer use of 2 hours or more increases the risk for pain at most anatomic sites.

There is a lack of longitudinal studies on the risk factors of lumbar discectomy. Using combined population survey and hospital discharge register data in a prospective longitudinal design, we investigated the association between adolescent risk factors and lumbar discectomy until early middle age. A prospective cohort of health survey respondents (n = 57,408) aged 14-18 years was followed for 651,000 person-years (average follow-up, 11.3 years). Study endpoints were lumbar discectomy, death or end of follow-up. Participants' mean age at the end of follow-up was 27 years. In multivariate Cox's regression analysis, the significant risk factor for lumbar discectomy among male respondents was daily smoking, HR being 1.5 (95% CI 1.1-2.2). In females, frequent participation in sports clubs (HR 2.7, 95% CI 1.1-6.3) and overweight (HR 2.1; 95% CI 1.1-4.1) were significantly associated with an increased risk of lumbar discectomy. Daily smoking in males and frequent participation in sports clubs and overweight in females measured at adolescence were statistically associated with lumbar discectomy at an 11-year follow-up, although the hazard ratios were relatively small. Further study of these common risk factors and their modifications may lead to a better understanding of the causes of lumbar disc herniation.

Low back pain (LBP) is common among adolescents and it has been estimated that one-fifth of adolescents suffer from recurrent severe LBP. However, longitudinal studies describing the risk factors of LBP are scarce. The purpose of this study was to investigate whether health, physical activity and other health behaviors, socio-demographic background and school success predict LBP hospitalization until early middle age. A cohort of 72,378 adolescents (57,408 respondents, response rate 79%) aged 14-18 years participating in a population survey between 1979 and 1997 was followed for an average of 11.1 years through the national hospital discharge register. We identified 810 (1.1%) persons with LBP hospitalization, 620 males (1.7% of the whole male cohort) and 190 (0.5%) females (HR 3.2; 95% CI: 2.7-3.7). In multivariate Cox's analysis, the strongest risk factors for LBP hospitalization for the whole cohort were weekly health complaints (HR 1.5; 95% CI: 1.2-1.9), daily smoking (HR 1.4; 95% CI: 1.1-1.7), and poor school success (HR 1.4; 95% CI: 1.1-1.9). Late puberty decreased the risk in males (HR 0.7; 95% CI: 0.5-0.9). Among females, participation in organized sports (HR 1.7; 95% CI: 1.1-2.5) was associated with an increased risk for LBP hospitalization. The associations between the risk factors and LBP hospitalization persisted into adulthood. Efforts to reduce adolescent smoking may decrease LBP-related morbidity in males. Coaches should pay special attention to the nature of physical training and personal exercises in females, and physiotherapists and sports physicians to the prevention of LBP hospitalization.