Claudia Franz

Study protocol. The Childhood Health, Activity, and Motor Performance School Study Denmark (The CHAMPS-study DK)

BackgroundAn increasingly passive life-style in the Western World has led to a rise in life-style related disorders. This is a major concern for all segments of society. The county council of the municipality of Svendborg in Denmark, created six Sport Schools with increased levels of suitable physical activities, which made it possible to study the health outcomes in these children whilst comparing them to children who attended the ‘normal’ schools of the region using the design of a “natural experiment”.MethodsChildren from the age of 6 till the age of 10, who accepted to be included in the monitoring process, were surveyed at baseline with questionnaires, physical examinations and physical and biological testing, including DXA scans. The physical examination and testing was repeated during the early stage of the study. Every week over the whole study period, the children will be followed with an automated mobile phone text message (SMS-Track) asking questions on their leisure time sports activities and the presence of any musculoskeletal problems. Children who report any such problems are monitored individually by health care personnel. Data are collected on demography, health habits and attitudes, physical characteristics, physical activity using accelerometers, motor performance, fitness, bone health, life-style disorders, injuries and musculoskeletal problems. Data collection will continue at least once a year until the children reach grade 9.DiscussionThis project is embedded in a local community, which set up the intervention (The Sport Schools) and thereafter invited researchers to provide documentation and evaluation. Sport schools are well matched with the ‘normal’ schools, making comparisons between these suitable. However, subgroups that would be specifically targeted in lifestyle intervention studies (such as the definitely obese) could be relatively small. Therefore, results specific to minority groups may be diluted. Nonetheless, the many rigorously collected data will make it possible to study, for example, the general effect that different levels of physical activity may have on various health conditions and on proxy measures of life-style conditions. Specifically, it will help answer the question on whether increased physical activity in school has a positive effect on health in children.

Overuse and traumatic extremity injuries in schoolchildren surveyed with weekly text messages over 2.5 years

The objectives of this prospective cohort study were to report the incidence, prevalence, and duration of traumatic and overuse injuries during a period of 2.5 years and to estimate the odds of injury types. In all, 1259 schoolchildren, aged 6–12, were surveyed each week with an automated mobile phone text message asking questions on the presence of any musculo‐skeletal problems and participation in leisure‐time sport. Children were examined and injuries classified as overuse or traumatic. The overall injury incidence and prevalence were 1.2% and 4.6% per week, with 2.5 times more overuse than traumatic injuries in lower extremities, and mean injury duration of 5.3 and 4.8 weeks, respectively. A reverse pattern was found for upper extremities, with 3.1 times more traumatic than overuse injuries and mean durations of 3.3 and 5.2 weeks, respectively. Grade level, school type, leisure‐time sport, and seasonal variation were associated with the risk of sustaining lower extremity injuries. Only grade level was associated with upper extremity injuries. The magnitude of overuse and traumatic limb injuries emphasizes the need for health professionals, coaches, and parents to pay special attention in relation to the growing and physically active child.

Musculoskeletal extremity injuries in a cohort of schoolchildren aged 6-12: a 2.5-year prospective study.

The objectives of this prospective school cohort study were to describe the epidemiology of diagnosed musculoskeletal extremity injuries and to estimate the injury incidence rates in relation to different settings, different body regions and injury types. In all, 1259 schoolchildren, aged 6–12, were surveyed weekly during 2.5 years using a new method of automated mobile phone text messaging asking questions on the presence of any musculoskeletal problems. All injuries were clinically diagnosed. Physical activity was measured from text messaging and accelerometers. A total number of 1229 injuries were diagnosed; 180 injuries in the upper extremity and 1049 in the lower extremity, with an overall rate of 1.59 injuries per 1000 physical activity units [95% confidence interval (CI) 1.50–1.68]. Upper extremities accounted for a rate of 0.23 (95% CI 0.20–0.27) and lower extremities accounted for 1.36 (95% CI 1.27–1.44). This study has added a wide overall perspective to the area concerning incidence and incidence rates of musculoskeletal extremity injuries in schoolchildren aged 6–12 years, including severe and less severe, traumatic, and overuse injuries. The understanding of injury epidemiology in children is fundamental to the acknowledgement and insurance of the appropriate prevention and treatment.

Total body fat percentage and body mass index and the association with lower extremity injuries in children: a 2.5-year longitudinal study

Background Overweight youths are generally recognised as being at increased risk of sustaining lower extremity injuries in sports. However, previous studies are inconclusive and choices for measuring overweight are manifold. Objective To examine two different measures of overweight, body mass index (BMI) and total body fat percentage (TBF%), as risk factors for lower limb injuries in a school-based cohort. Study design A longitudinal cohort study. Methods A total of 632 school children, baseline age 7.7–12.0 years, were investigated. Whole body dual energy x-ray absorptiometry scans provided measures of TBF%. Measures of BMI were obtained by standard anthropometric methods. Musculoskeletal complaints were reported by parents answering weekly mobile phone text messages during 2.5 years. Injuries were diagnosed by clinicians. Leisure time sports participation was reported weekly using text messaging. Results During 2.5 years of follow-up, 673 lower extremity injuries were diagnosed. Children being overweight by both BMI and TBF% showed the highest risk of sustaining lower extremity injuries (IRR 1.38 (95% CI 1.05 to 1.81)). Children who were overweight using BMI and TBF% showed the highest risk of sustaining lower extremity injuries (IRR 1.38 (95% CI 1.05 to 1.81)). Conclusions The risk of lower extremity injuries appeared to be increased for overweight children. When comparing two different measures of overweight, overweight by TBF% is a higher risk factor than overweight by BMI. This suggests that a high proportion of adiposity is more predictive of lower extremity injuries, possibly due to a lower proportion of lean muscle mass.

Injuries in children with extra physical education in primary schools.

PURPOSE (1) Examine the influence of extra physical education (EPE) on the number of musculoskeletal injuries in public schools accounting for organized sports participation (OSP) outside school. (2) Examine the major injury subgroup: growth-related overuse (GRO) through the overuse-related injury group. METHODS A longitudinal controlled school-based study among Danish public schools. At baseline, 1216 children participated age 6.2-12.4 yr. Six schools (701 children) with EPE and four control schools (515 children) were followed up with weekly automated mobile phone text messages for information on musculoskeletal problems and OSP. Health care personnel diagnosed the children according to the World Health Organizations International Classification of Diseases, Tenth Revision. Data were analyzed using a two-part zero-inflated negative binomial (ZINB) regression model. RESULTS School type had no influence on the odds of sustaining an injury but increased the probability of sustaining a higher injury count for children with injuries, with total injuries by a factor of 1.29 (95% confidence interval [CI] = 1.07-1.56), overuse by a factor of 1.29 (95% CI = 1.06-1.55), and GRO by a factor of 1.38 (95% CI = 1.02-1.80). Weekly mean OSP decreased the odds of belonging to the group of children with no injuries, by a factor of 0.29 (95% CI = 0.14-0.58), 0.26 (95% CI = 0.14-0.48), and 0.17 (95% CI = 0.06-0.52) for total, overuse, and GRO, respectively. OSP also increased the probability of sustaining a higher injury count for children with injuries by a factor of 1.11 (95% CI = 1.02-1.22), 1.10 (95% CI = 1.00-1.22), and 1.14 (95% CI = 1.00-1.30), respectively. CONCLUSIONS Children enrolled in EPE schools with high OSP have the highest odds of injury and a high probability of sustaining a higher injury count compared to their peers at schools with normal PE. Special attention should be assigned to these children during compulsory PE.

Back pain in children surveyed with weekly text messages - a 2.5 year prospective school cohort study

BackgroundBack pain is reported to occur already in childhood, but its development at that age is not well understood. The aims of this study were to describe BP in children aged 6-12 years, and to investigate any sex and age differences.MethodsData on back pain (defined as pain in the neck, mid back and/or lower back) were collected once a week from parents replying to automated text-messages over 2.5 school years from 2008 till 2011. The prevalence estimates were presented as percentages and 95% confidence intervals. Differences between estimates were considered significant if confidence intervals did not overlap. A test for trend, using a multi-level mixed-effects logistic regression extended to the longitudinal and multilevel setting, was performed to see whether back pain reporting increased with age.ResultsDepending on the age group, 13-38% children reported back pain at least once per survey year, and 5-23% at least twice per survey year. The average weekly prevalence estimate ranged between 1% and 5%. In the final survey year more girls than boys reported back pain at least twice. The prevalence estimates did not increase monotonically with age but showed a greater increase in children younger than 9/10, after which they remained relatively stable up to the age of 12 years.ConclusionsWe found that back pain was not a common problem in this age group and recommend health professionals be vigilant if a child presents with constant or recurring back pain. Our results need to be supplemented by a better understanding of the severity and consequences of back pain in childhood. It would be productive to study the circumstances surrounding the appearance of back pain in childhood, as well as, how various bio-psycho-social factors affect its onset and later recurrence. Knowledge about the causes of back pain in childhood might allow early prevention.

Seasonal variation in musculoskeletal extremity injuries in school children aged 6-12 followed prospectively over 2.5 years: a cohort study

Objectives The type and level of physical activity in children vary over seasons and might thus influence the injury patterns. However, very little information is available on the distribution of injuries over the calendar year. This study aims to describe and analyse the seasonal variation in extremity injuries in children. Design Prospective cohort study. Setting 10 public schools in the municipality of Svendborg, Denmark. Participants A total of 1259 school children aged 6–12 years participating in the Childhood Health, Activity, and Motor Performance School Study Denmark. Methods School children were surveyed each week during 2.5 school-years. Musculoskeletal injuries were reported by parents answering automated mobile phone text questions (SMS-Track) on a weekly basis and diagnosed by clinicians. Data were analysed for prevalence and incidence rates over time with adjustments for gender and age. Results Injuries in the lower extremities were reported most frequently (n=1049). There was a significant seasonal variation in incidence and prevalence for lower extremity injuries and for lower and upper extremity injuries combined (n=1229). For the upper extremities (n=180), seasonal variation had a significant effect on the risk of prevalence. Analysis showed a 46% increase in injury incidence and a 32% increase in injury prevalence during summer relative to winter for lower and upper extremity injuries combined. Conclusions There are clear seasonal differences in the occurrence of musculoskeletal extremity injuries among children with almost twice as high injury incidence and prevalence estimates during autumn, summer and spring compared with winter. This suggests further research into the underlying causes for seasonal variation and calls for preventive strategies to be implemented in order to actively prepare and supervise children before and during high-risk periods.

Leisure-time sport and overuse injuries of extremities in children age 6–13, a 2.5 years prospective cohort study: the CHAMPS-study DK

Objectives It is not known which sports are most likely to cause overuse injuries of the extremities in children. In this study, we report on the incidence of overuse injuries of the upper and lower extremities in children who participate in various leisure-time sports and relate this to the frequency of sport sessions. Design Natural experiment including a prospective cohort study. Setting 10 state schools in 1 Danish municipality: Svendborg. Participants 1270 children aged 6–13 years participating in the Childhood Health, Activity, and Motor Performance School Study Denmark. Outcomes measures Over 2.5 years, parents answered weekly SMS-track messages (a) on type and frequency of leisure-time sports undertaken by their child, and (b) reporting if their child had experienced any musculoskeletal pain. Children with reported pain were examined by a clinician and diagnosed as having an overuse injury of an extremity or not. The incidence of diagnosed overuse injury was calculated for each of the 9 most common sports in relation to 5-week periods. Incidence by frequency of sessions was calculated, and multivariable analysis was performed taking into account age, sex and frequency of physical education classes at school. Results Incidence of overuse injuries of the lower extremity ranged from 0.2 to 3.3 for the 9 sports, but was near 0 for overuse injuries of the upper extremities. There was no obvious dose–response. The multivariate analysis showed soccer and handball to be the sports most likely to result in an overuse injury. Conclusions Among a general population of schoolchildren, overuse injuries of the lower extremities were not common and overuse injuries of the upper extremities were rare. Organised leisure-time sport, as practised in Denmark, can be considered a safe activity for children.

Physical activity is prospectively associated with spinal pain in children (CHAMPS Study-DK)

AbstarctSpinal pain and physical inactivity are critical public health issues. We investigated the prospective associations of physical activity intensity with spinal pain in children. Physical activity was quantified with accelerometry in a cohort of primary school students. Over 19 months, parents of primary school students reported children’s spinal pain status each week via text-messaging (self-reported spinal pain). Spinal pain reports were followed-up by trained clinicians who diagnosed each child’s complaint and classified the pain as non-traumatic or traumatic. Associations were examined with logistic regression modeling using robust standard errors and reported with odds ratios (OR). Children (n = 1205, 53.0% female) with mean ± SD age of 9.4 ± 1.4 years, participated in 75,180 weeks of the study. Nearly one-third (31%) of children reported spinal pain, and 14% were diagnosed with a spinal problem. Moderate intensity physical activity was protectively associated with self-reported [OR(95%CI) = 0.84(0.74, 0.95)], diagnosed [OR(95%CI) = 0.79(0.67, 0.94)] and traumatic [OR(95%CI) = 0.77(0.61, 0.96)] spinal pain. Vigorous intensity physical activity was associated with increased self-reported [OR(95%CI) = 1.13(1.00, 1.27)], diagnosed [OR(95%CI) = 1.25(1.07, 1.45)] and traumatic [OR(95%CI) = 1.28(1.05, 1.57)] spinal pain. The inclusion of age and sex covariates weakened these associations. Physical activity intensity may be a key consideration in the relationship between physical activity behavior and spinal pain in children.

Back injuries in a cohort of schoolchildren aged 6–12: A 2.5-year prospective study

The aims of this prospective school cohort study were to describe the epidemiology of diagnosed back pain in childhood, classified as either nontraumatic or traumatic back injury, and to estimate the association with physical activity in different settings. Over 2.5 years, 1240 children aged 6–12 years were surveyed weekly using mobile text messages to ask about the presence or absence of back pain. Pain was clinically diagnosed and injuries were classified using the International Classification of Diseases version 10. Physical activity data were obtained from text messages and accelerometers. Of the 315 back injuries diagnosed, 186 injuries were nontraumatic and 129 were traumatic. The incidence rate ratio was 1.5 for a nontraumatic back injury compared with a traumatic injury. The overall estimated back injury incidence rate was 0.20 per 1000 physical activity units (95% confidence interval 0.18–0.23). The back injury incidence rates were higher for sports when exposure per 1000 physical activity units was taken into consideration and especially children horse‐riding had a 40 times higher risk of sustaining a traumatic back injury compared to the risk during non‐organized leisure time physical activity. However, the reasonably low injury incidence rates support the recommendations of children continuously being physically active.