The associations of physical activity with fracture risk--a 7-year prospective controlled intervention study in 3534 children

Racial/Ethnic Differences in Bone Mineral Density for Osteoporosis

PURPOSE OF REVIEW

We primarily aim to review differences in bone mineral density (BMD) for osteoporosis among different racial/ethnic groups and to highlight the magnitude of racial/ethnic differences in obesity and diabetes. We also explore the factors contributing to the BMD differences among various subgroups. In addition, we investigate the existing disparities in research, educational initiatives, screening practices, and treatment options for osteoporosis and discuss these findings' clinical and public health implications.

RECENT FINDINGS

Racial/ethnic differences in BMD for osteoporosis exist in the USA and other countries. There are disparities regarding osteoporosis screening and treatment. Understanding the factors contributing to these differences can help develop targeted interventions and policies to reduce their impact. Clinicians should consider the racial/ethnic differences in BMD when making treatment decisions and providing preventive care. Future research could contribute to developing effective strategies for preventing osteoporosis among different racial/ethnic groups. This review offered a comprehensive examination of differences in BMD across various racial and ethnic groups, elucidating the influence of genetic, lifestyle, and cultural factors on these differences. This review also highlighted the disparities in osteoporosis screening, treatment options, research on medical effectiveness, and educational outreach tailored to each subgroup. Recognizing the importance of addressing these inequalities, we present this review to advocate for targeted interventions to reduce disparities in osteoporosis and improve bone health for all populations.

Exposure to Neighborhood Walkability and Residential Greenness and Incident Fracture

Importance

Emerging studies have suggested that environmental factors are associated with fracture. However, little is known about the association of neighborhood walkability and residential greenness with fracture.

Objective

To investigate the association of long-term exposure to walkability and greenness with incident fracture and explore the potential interaction effect.

Design, Setting, and Participants

This cohort study recruited participants aged 40 years or older in Ningbo, China from June 2015 to January 2018. Participants were observed for outcomes through February 2023, with data analysis conducted in March 2023.

Exposures

Neighborhood walkability was measured by a modified walkability calculation method according to a walk score tool. Residential greenness was assessed by satellite-derived normalized difference vegetation index (NDVI) within a 1000-m buffer.

Main Outcomes and Measures

Incident fracture was ascertained according to International Statistical Classification of Diseases and Related Health Problems, Tenth Revision codes via the Yinzhou Health Information System. Cox proportional hazards models were fit, with age as time scale to estimate the associations of walkability and greenness with fracture. Potential effect modification was explored by covariates, as well as the interactive effect of walkability and greenness.

Results

A total of 23 940 participants were included in this study with 13 735 being female (57.4%). The mean (SD) age at baseline was 63.4 (9.4) years. During a follow-up period of 134 638 person-years, 3322 incident fractures were documented. In the full adjusted model, every IQR increment in neighborhood walkability and residential greenness was associated with a hazard ratio (HR) of 0.88 (95% CI, 0.83-0.92) and 0.84 (95% CI, 0.80-0.89), respectively, for fracture. Furthermore, the association of greenness and fracture was greater with an increase in walkability. The HR (Q4 vs Q1) for greenness was 0.62 (95% CI, 0.46-0.82) in neighborhoods with the highest quartile of walkability.

Conclusions and Relevance

This population cohort study suggested that long-term exposure to neighborhood walkability and residential greenness were both associated with lower risk of incident fracture. The benefits of greenness increased in more walkable areas.

Bone Health in Young Athletes: a Narrative Review of the Recent Literature

PURPOSE OF REVIEW

The aim of this review is to discuss the most recent published scientific evidence regarding bone health in the pediatric athlete.

RECENT FINDINGS

Pediatric athletes commonly suffer from overuse injuries to the physes and apophyses, as well as bone stress injuries, for which magnetic resonance imaging grading of the severity of injuries may be useful in guiding return to sport. Adolescent athletes, particularly those who train indoors and during the winter season, are at risk for vitamin D deficiency, which has important implications for bone mineral density. However, the relationship between vitamin D status and traumatic fracture risk is still unclear. While the female athlete triad is a well-established condition, the current work has led to the recognition of parallel pathophysiology in male athletes, referred to as the male athlete triad. Recent evidence suggests that transdermal 17β-estradiol treatment in amenorrhoeic female athletes is an effective adjunctive treatment to improve bone mineral density in treatment of the female athlete triad. Young athletes are at risk for musculoskeletal injuries unique to the growing skeleton. Optimizing nutritional intake, particularly related to adequate vitamin D intake and prevention of the athlete triad, is critical to optimize bone health in the young athlete.

The Benefits to Bone Health in Children and Pre-School Children with Additional Exercise Interventions: A Systematic Review and Meta-Analysis

OBJECTIVE

Determine if exercise interventions, beyond what is already provided to children and preschool children, improve bone health and reduce fracture incidence.

DESIGN

Systematic review and meta-analysis reported using the PRISMA guidelines. Certainty of evidence was assessed using GRADE recommendations.

DATA SOURCES

Five electronic databases were searched for records: PUBMED; CINAHL; CENTRAL; SPORTDiscus; Web of Science.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Randomised, quasi-randomised and non-randomised controlled trials (including cluster-randomised) assessing the impact of additional exercise interventions (e.g., increased physical education classes or specific jumping programs) on bone health in children (6-12 years) and pre-school children (2-5 years) without dietary intervention.

RESULTS

Thirty-one records representing 16 distinct clinical trials were included. Dual-energy X-ray Absorptiometry (DXA) and/or peripheral Quantitative Computed Tomography (pQCT) were used to quantify bone health. Increased femoral neck bone mineral content in children with additional exercise interventions (n = 790, SMD = 0.55, 95% CI = 0.01 to 1.09) was reported, however this was not significant following sensitivity analysis. Other DXA and pQCT measures, as well as fracture incidence, did not appear to significantly differ over time between intervention and control groups. No studies reported adverse events. Studies failed to report all domains within the TIDieR checklist. All studies were at high risk of bias using the Cochrane RoB Tool 2.0. The certainty of the evidence was very low.

CONCLUSIONS

The addition of exercise interventions, beyond what is provided to children, does not appear to improve DXA and pQCT measures of bone health. The effect of additional exercise interventions on bone health in pre-school children is largely unknown. Future trials should ensure adherence is clearly reported and controlled for within analysis as well as including reports of adverse events (e.g., apophysitis) that occur due to increased exercise interventions.

Physical Activity in Late Prepuberty and Early Puberty Is Associated With High Bone Formation and Low Bone Resorption

Background

Physical activity (PA) increases bone mass, especially in late prepuberty and early puberty, but it remains unclear if and how PA affects both bone formation and bone resorption.

Materials and Methods

We included 191 boys and 158 girls aged 7.7 ± 0.6 (mean ± SD) in a population-based PA intervention study. The intervention group (123 boys and 94 girls) received daily physical education (PE) in school (40 min/day; 200 min/week) from study start and during the nine compulsory school years in Sweden. The controls (68 boys and 64 girls) received the national standard of 1–2 classes PE/week (60 min/week). During the intervention, blood samples were collected at ages 9.9 ± 0.6 (n = 172; all in Tanner stages 1–2) and 14.8 ± 0.8 (n = 146; all in Tanner stages 3–5) and after termination of the intervention at age 18.8 ± 0.3 (n = 93; all in Tanner stage 5) and 23.5 ± 0.7 (n = 152). In serum, we analyzed bone formation markers [bone-specific alkaline phosphatase (bALP), osteocalcin (OC), and N-terminal propeptide of collagen type 1 (PINP)] and bone resorption markers [C-terminal telopeptide cross links (CTX) and tartrate-resistant acid phosphatase (TRAcP 5b)]. Linear regression was used to compare age and sex-adjusted mean differences between intervention children and controls in these markers.

Results

Two years after the intervention was initiated (at Tanner stages 1–2), we found higher serum levels of bALP and OC, and lower serum levels of TRAcP 5b in the intervention compared with the control group. The mean difference (95% CI) was for bALP: 13.7 (2.1, 25.3) μg/L, OC: 9.1 (0.1, 18.1) μg/L, and TRAcP 5b: −2.3 (−3.9, −0.7) U/L. At Tanner stages 3–5 and after the intervention was terminated, bone turnover markers were similar in the intervention and the control children.

Conclusion

Daily school PA in the late prepubertal and early pubertal periods is associated with higher bone formation and lower bone resorption than school PA 1–2 times/week. In late pubertal and postpubertal periods, bone formation and resorption were similar. Termination of the intervention is not associated with adverse bone turnover, indicating that PA-induced bone mass benefits gained during growth may remain in adulthood.

Decreases in pediatric fractures during the COVID-19 pandemic - a nationwide epidemiological cohort study

The COVID-19 pandemic led to fundamental changes in daily routines of children. Our aim was to evaluate the incidence and characteristics of fractures among Israeli children during 2020 compared with 2015-2019. Demographic, clinical data, and incidence rates of fractures in individuals aged < 18 years were derived from the electronic database of Meuhedet Health Services, which provides healthcare services to 1.2 million people in Israel. We further subdivided the year to five periods according to government regulations of lockdown and isolation at each period. Fracture sites were determined according to ICD9 definitions. During 2020, 10,701 fractures occurred compared with 12,574 ± 599 fractures per year during 2015-2019 (p-value < 0.001). Fracture rates were lower during all periods in 2020. The largest decline was observed during the first lockdown for both boys (56% decline, 95% confidence interval [CI] 52-60%) and girls (47% decline CI 41-53%). While the fracture rate declined for most age groups, the largest decline was recorded for the age group 11-14 years, with significant reduction rates of 66% (CI 59-71%) for boys and 65% (CI 54-73%) for girls. The most prominent declines were of fractures of the hand bones of both boys and girls (64% and 59%, respectively). Conclusions: Our data showed a significant decrease in fracture rate in 2020 compared to the previous 5 years, as well as differences between periods within that year. What is New: •The COVID-19 pandemic led to fundamental change in daily routines of children with significant decrease in school attendance and sport activities. •Consequent to these public health measures, the incidence rate of pediatric fractures decreased significantly. What is New: •This study demonstrates declines in fracture rates during lockdown periods, with only partial reversing of the trends between the lockdown periods. •The most pronounced decline was observed during the first lockdown period. •The decline was most prominent in children aged 11-14 years; there was no significant change in fracture incidence of children aged <3 years.

Epidemiology of childhood fractures in Israel during 2000-2019

BACKGROUND

Differences have been reported in incidence rates of fractures in the pediatric population, between countries and over time. The aim of this study was to evaluate the incidence and characteristics of fractures over 20 years among Israeli children.

METHODS

Incidence rates of fractures were derived from the electronic database of Meuhedet Health Services, a health maintenance organization providing healthcare services to 1.2 million people in Israel. Demographic and clinical data were extracted of all the fractures in individuals aged <18 years during 2000-2019. Fracture sites were determined according to ICD9 definitions. Fracture data were analyzed by age, sex, season and sector (general Jewish population, ultra-orthodox Jews and Arabs).

RESULTS

During the study period 188,283 fractures occurred in 142,049 individuals. The most common were fractures of the upper limb (65%), followed by fractures of the lower limb [20%]. The overall fracture rate was 251 per 10,000 person- years (PY), and was higher for boys than girls (319 vs. 180 per 10,000 PY, p < 0.001). During 20 years, standardized fracture rates decreased significantly in the general Jewish population, among both boys (from 457 to 325 per 10,000 PY, p < 0.001) and girls (from 244 to 196 per 10,000 PY, p < 0.001); increased among ultra-orthodox Jewish boys (from 249 to 285 per 10,000 PY, p = 0.002) and girls (from 147 to 194 per 10,000 PY, p < 0.001); and did not change significantly among Arab boys and girls. The fracture rate peaked among girls aged 10-11 years and among boys aged 12-13 years. Seasonal variation showed a bimodal distribution with peaks during spring and autumn.

CONCLUSIONS

The incidence of pediatric fractures is affected by age, gender, sector and season. Recognition of fracture characteristics may help identify specific populations and conditions for targeted prevention strategies.

Musculoskeletal Benefits from a Physical Activity Program in Primary School are Retained 4 Years after the Program is Terminated

Daily school physical activity (PA) improves musculoskeletal traits. This study evaluates whether the benefits remain 4 years after the intervention. We followed 45 boys and 36 girls who had had 40 min PA/school day during the nine compulsory school years and 21 boys and 22 girls who had had 60 min PA/school week (reference), with measurements at baseline and 4 years after the program terminated. Bone mineral content (BMC; g) and bone mineral density (BMD; g/cm²) were measured by dual-energy X-ray absorptiometry and knee flexion peak torque relative to total body weight (PT_flexTBW) at a speed of 180 degrees/second with a computerized dynamometer. Group differences are presented as mean differences (adjusted for sex and duration of follow-up period) with 95% confidence intervals. The total gain bone mass [mean difference in spine BMC +32.0 g (14.6, 49.4) and in arms BMD of +0.06 g/cm² (0.02, 0.09)] and gain in muscle strength [mean difference in PT_flex180TBW +12.1 (2.0, 22.2)] were greater in the intervention than in the control group. There are still 4 years after the intervention indications of benefits in both bone mass and muscle strength gain. Daily school PA may counteract low bone mass and inferior muscle strength in adult life. ClinicalTrials.gov.NCT000633828 retrospectively registered 2008-11-03.

School-based physical activity programs for promoting physical activity and fitness in children and adolescents aged 6 to 18

BACKGROUND

Physical activity among children and adolescents is associated with lower adiposity, improved cardio-metabolic health, and improved fitness. Worldwide, fewer than 30% of children and adolescents meet global physical activity recommendations of at least 60 minutes of moderate to vigorous physical activity per day. Schools may be ideal sites for interventions given that children and adolescents in most parts of the world spend a substantial amount of time in transit to and from school or attending school.

OBJECTIVES

The purpose of this review update is to summarise the evidence on effectiveness of school-based interventions in increasing moderate to vigorous physical activity and improving fitness among children and adolescents 6 to 18 years of age. Specific objectives are: • to evaluate the effects of school-based interventions on increasing physical activity and improving fitness among children and adolescents; • to evaluate the effects of school-based interventions on improving body composition; and • to determine whether certain combinations or components (or both) of school-based interventions are more effective than others in promoting physical activity and fitness in this target population.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, CINAHL, PsycINFO, BIOSIS, SPORTDiscus, and Sociological Abstracts to 1 June 2020, without language restrictions. We screened reference lists of included articles and relevant systematic reviews. We contacted primary authors of studies to ask for additional information.

SELECTION CRITERIA

Eligible interventions were relevant to public health practice (i.e. were not delivered by a clinician), were implemented in the school setting, and aimed to increase physical activity among all school-attending children and adolescents (aged 6 to 18) for at least 12 weeks. The review was limited to randomised controlled trials. For this update, we have added two new criteria: the primary aim of the study was to increase physical activity or fitness, and the study used an objective measure of physical activity or fitness. Primary outcomes included proportion of participants meeting physical activity guidelines and duration of moderate to vigorous physical activity and sedentary time (new to this update). Secondary outcomes included measured body mass index (BMI), physical fitness, health-related quality of life (new to this update), and adverse events (new to this update). Television viewing time, blood cholesterol, and blood pressure have been removed from this update.  DATA COLLECTION AND ANALYSIS: Two independent review authors used standardised forms to assess each study for relevance, to extract data, and to assess risk of bias. When discrepancies existed, discussion occurred until consensus was reached. Certainty of evidence was assessed according to GRADE. A random-effects meta-analysis based on the inverse variance method was conducted with participants stratified by age (children versus adolescents) when sufficient data were reported. Subgroup analyses explored effects by intervention type.

MAIN RESULTS

Based on the three new inclusion criteria, we excluded 16 of the 44 studies included in the previous version of this review. We screened an additional 9968 titles (search October 2011 to June 2020), of which 978 unique studies were potentially relevant and 61 met all criteria for this update. We included a total of 89 studies representing complete data for 66,752 study participants. Most studies included children only (n = 56), followed by adolescents only (n = 22), and both (n = 10); one study did not report student age. Multi-component interventions were most common (n = 40), followed by schooltime physical activity (n = 19), enhanced physical education (n = 15), and before and after school programmes (n = 14); one study explored both enhanced physical education and an after school programme. Lack of blinding of participants, personnel, and outcome assessors and loss to follow-up were the most common sources of bias.  Results show that school-based physical activity interventions probably result in little to no increase in time engaged in moderate to vigorous physical activity (mean difference (MD) 0.73 minutes/d, 95% confidence interval (CI) 0.16 to 1.30; 33 studies; moderate-certainty evidence) and may lead to little to no decrease in sedentary time (MD -3.78 minutes/d, 95% CI -7.80 to 0.24; 16 studies; low-certainty evidence). School-based physical activity interventions may improve physical fitness reported as maximal oxygen uptake (VO₂max) (MD 1.19 mL/kg/min, 95% CI 0.57 to 1.82; 13 studies; low-certainty evidence). School-based physical activity interventions may result in a very small decrease in BMI z-scores (MD -0.06, 95% CI -0.09 to -0.02; 21 studies; low-certainty evidence) and may not impact BMI expressed as kg/m² (MD -0.07, 95% CI -0.15 to 0.01; 50 studies; low-certainty evidence). We are very uncertain whether school-based physical activity interventions impact health-related quality of life or adverse events.

AUTHORS' CONCLUSIONS

Given the variability of results and the overall small effects, school staff and public health professionals must give the matter considerable thought before implementing school-based physical activity interventions. Given the heterogeneity of effects, the risk of bias, and findings that the magnitude of effect is generally small, results should be interpreted cautiously.

Exercise in school Physical Education increase bone mineral content and density: Systematic review and meta-analysis

ABSTRACTThis systematic review and meta-analysis aimed to evaluate the effectiveness of interventions through Physical Education (PE) exercises on bone mineral content (BMC) and density (BMD) of children and adolescents. The research was conducted using the online electronic databases PubMed, Science Direct, Web of Science and Scopus (March 2021). The analysis was restricted to school-based studies that examined the effect of PE interventions on BMC and BMD in schoolchildren (<18 years old). Standardised mean differences (SMD) with 95% confidence interval (CI) and random-effects models were calculated. The heterogeneity and inconsistency of the studies were estimated using Cochran's Q-statistic and I², respectively. Twenty-two studies with 2,556 participants were selected. PE interventions were associated with a significant increase in BMC (SMD = 1.348; 95% CI, 1.053-1.643) and BMD (SMD = 0.640; 95% CI, 0.417-0.862). Femoral neck subgroup analysis indicate an increase in BMC for boys (SMD = 1.527; 95% CI, 0.990-2.065) and girls (SMD = 1.27; 95% CI, 0.782-1.767), and in BMD for boys (SMD = 0.518; 95% CI, 0.064-0.972) and girls (SMD = 0.817; 95% CI, 0.349-1.284). Finally, increases are reported in the lumbar spine BMC for boys (SMD = 1.860; 95% CI, 1.018-2.700) and girls (SMD = 1.275; 95% CI, 0.782-1.767). This meta-analysis provides insights into the effectiveness of interventions aimed at including physical exercise in PE on bone mass, suggesting that increasing the proportion of curriculum time allocated to PE may improve students' BMD and BMC, especially in the femoral neck and lumbar spine.

Time trends in pediatric hand fracture incidence in Malmö, Sweden, 1950-2016

Background

The hand is the second most fractured region in children. It is therefore important to update fracture epidemiology to be able to identify time trends for adequate health care planning. This study reports pediatric hand fracture incidence 2014–2016 and, using published data, also long-term time trends in 1950–2016.

Patients and methods

The Swedish city of Malmö, with 328,494 inhabitants in 2016, has only one hospital. We used the hospital radiological archive, medical charts, and diagnosis registry to identify hand fractures in city residents < 16 years in 2014–2016. These data were compared to those from three published studies that evaluated periods in 1950–2006. Differences between two periods were calculated as both unadjusted and age- and sex-adjusted incident rate ratios (IRR) with 95% confidence intervals (95% CI). We used joinpoint regression to estimate time trends during the entire period and present annual percent changes (APC) with 95% CI.

Results

In 2014–2016 phalangeal fractures accounted for 71% of all hand fractures, metacarpal fractures for 24%, and carpal fractures for 5%. We identified 615 hand fractures (419 in boys and 196 in girls) during 181,617 person-years in 2014–2016, resulting in an unadjusted pediatric hand fracture incidence of 339/100,000 person-years (boys 452/100,000 person-years and girls 220/100,000 person-years). The age-adjusted incidence 2014–2016 was similar to 2005–2006, the most recently evaluated period (IRR in boys 0.9; 95% CI 0.8 to 1.01, and in girls 1.0; 95% CI 0.8 to 1.2). Looking at the entire period 1950–2016, we found that age-adjusted incidence increased in 1950–1979, in boys by APC + 3.8%; 95% CI 3.0 to 4.5 and in girls by + 3.9%; 95% CI 2.8 to 5.0, but decreased in 1979–2016, in boys by − 0.7%; 95% CI − 1.4 to − 0.003, and girls by − 1.3%; 95% CI − 2.4 to − 0.1.

Conclusions

Phalangeal fractures accounted for about three quarters of all hand fractures. The age-adjusted hand fracture incidence increased in both sexes in 1950–1979 and decreased in 1979–2016.

Level of evidence

III

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-021-02380-y.

Childhood Distal Forearm Fracture Incidence in Malmö, Sweden 1950 to 2016

Background  Distal forearm fracture is the most common pediatric fracture. As studies have indicated time trends in fracture incidence, we wanted to update the epidemiology and estimate time trends between 1950 and 2016 in Malmö, Sweden. Methods  The city of Malmö, Sweden, had 318,107 inhabitants (58,585 of the population was aged <16 years) in 2014 and one hospital. We, therefore, used the hospital diagnosis registry and hospital medical records to identify and classify distal forearm fractures 2014 to 2016 in children aged 0 to 15 years. For long-term trend calculations, we also included published data from 1950 to 2006 (resulting in 17 evaluated years) and used joinpoint regression to estimate annual percent changes (APC). To describe differences in incidence between two periods, we calculated incident rate ratios (IRR) with 95% confidence intervals (95% CI) to describe uncertainty. Results  Childhood distal forearm fracture incidence in 2014 to 2016 was 546/100,000 person-years (660 in boys and 427 in girls). The age-adjusted incidence in 2014 to 2016 and in 2005 to 2006 was similar (boys IRR 1.0, 95% CI: 0.9-1.2 and girls IRR 1.1, 95% CI: 0.9-1.3). Time-trend analyses from 1950 to 2016 revealed increasing age-adjusted incidence in both boys (APC +0.9%, 95% CI: 0.7-1.2) and girls (APC +0.6%, 95% CI: 0.3-0.9). Conclusion  Distal forearm fracture incidence was similar in 2014 to 2016 and in 2005 to 2006. Age-adjusted incidence had increased in both sexes from 1950 to 2016. Level of Evidence  This is a Level III b study.

Weight Management in Youth with Type 1 Diabetes and Obesity: Challenges and Possible Solutions

PURPOSE OF REVIEW

This review highlights challenges associated with weight management in children and adolescents with type 1 diabetes (T1D). Our purpose is to propose potential solutions to improve weight outcomes in youth with T1D.

RECENT FINDINGS

A common barrier to weight management in T1D is reluctance to engage in exercise for fear of hypoglycemia. Healthcare practitioners generally provide limited guidance for insulin dosing and carbohydrate modifications to maintain stable glycemia during exercise. Adherence to dietary guidelines is associated with improved glycemia; however, youth struggle to meet recommendations. When psychosocial factors are addressed in combination with glucose trends, this often leads to successful T1D management. Newer medications also hold promise to potentially aid in glycemia and weight management, but further research is necessary. Properly addressing physical activity, nutrition, pharmacotherapy, and psychosocial factors while emphasizing weight management may reduce the likelihood of obesity development and its perpetuation in this population.

Impact of sports participation on incidence of bone traumatic fractures and health-care costs among adolescents: ABCD - Growth Study

Objective: To analyze the risk of bone traumatic fractures according to the engagement in sports, as well as to identify the potential impact of sports participation and traumatic fractures on health-care costs among adolescents. Methods: This is a longitudinal 12-month study of 285 adolescents of both sexes in Brazil. We assessed the occurrence of traumatic fractures and health-care services (hospitalizations, medicine use, medical consultations, and exams) by phone contact every month for 12 months. Adolescents were divided into four groups according to sport characteristics: non-sport (n = 104), non-impact sport (swimming [n = 34]), martial arts (n = 49 [judo, karate, kung-Fu]) and impact sports (n = 98 [track-and-field, basketball, gymnastics, tennis, and baseball]). Results: The incidence of new fractures was 2.1%. The overall costs accounted during the 12-month follow-up were U$ 3,259.66. Swimmers (US$ 13.86) had higher health-care costs than non-sport (US$ 1.82), martial arts (US$ 2.23), and impact sports (US$ 2.32). Conclusion: swimming seems to be related to higher health-care costs among adolescents.

Exercise and Peak Bone Mass

PURPOSE OF REVIEW

The main goal of this narrative review is to assess whether physical activity (PA) influences peak bone mass and fracture risk.

RECENT FINDINGS

Several randomized controlled trials (RCT) show that short-term PA intervention programs in childhood improve the accrual of bone mineral. There are now also long-term controlled PA intervention studies demonstrating that both boys and girls with daily school PA through puberty gain higher bone mineral content (BMC) and bone mineral density (BMD) and greater bone size than boys and girls with school PA 1-2 times/week. These benefits seem to be followed by a gradual reduction in expected fracture rates, so that in children with daily school PA, the incidence rate ratio (IRR) after 8 years is less than half that expected by age. Daily school PA from before to after puberty is associated with beneficial gains in bone traits and gradually lower relative fracture risk.

Daily School Physical Activity from Before to After Puberty Improves Bone Mass and a Musculoskeletal Composite Risk Score for Fracture

This 7.5-year prospective controlled exercise intervention study assessed if daily school physical activity (PA), from before to after puberty, improved musculoskeletal traits. There were 63 boys and 34 girls in the intervention group (40 min PA/day), and 26 boys and 17 girls in the control group (60 min PA/week). We measured musculoskeletal traits at the start and end of the study. The overall musculoskeletal effect of PA was also estimated by a composite score (mean Z-score of the lumbar spine bone mineral content (BMC), bone area (BA), total body lean mass (TBLM), calcaneal ultrasound (speed of sound (SOS)), and muscle strength (knee flexion peak torque)). We used analyses of covariance (ANCOVA) for group comparisons. Compared to the gender-matched control group, intervention boys reached higher gains in BMC, BA, muscle strength, as well as in the composite score, and intervention girls higher gains in BMC, BA, SOS, as well as in the composite score (all p < 0.05, respectively). Our small sample study indicates that a daily school-based PA intervention program from Tanner stage 1 to 5 in both sexes is associated with greater bone mineral accrual, greater gain in bone size, and a greater gain in a musculoskeletal composite score for fractures.

Do teenagers return to normal physical activity levels after limb fractures? A longitudinal, accelerometry-based, activity monitoring study

PURPOSE

This study aimed to elucidate whether levels of physical activity (PA) return to normal after bone healing or whether long-term behavioural changes in PA are to be expected in children and teenagers who have sustained limb fractures.

METHODS

In all, 100 children and teenagers with a first episode of limb fracture and 100 sex- and age-matched healthy controls (CTRL) were recruited for a prospective study. PA in limb fracture patients was assessed at 18-month follow-up using accelerometer measurements, and values were compared with those of CTRL. Time spent in PA at different levels of intensity was determined for each participant and expressed in minutes and as a percentage of total validly measured time.

RESULTS

Mean levels of PA at different levels of intensity by previously injured children and teenagers were similar than CTRL (42 sets of paired data). However, time spent in moderate-to-vigorous PA (MVPA) was lower than 60 minutes among limb-fracture patients at 18-month follow-up.

CONCLUSION

The amount of skeletal loading in children and teenagers returns to normal values by 18 months after limb fracture. Even if time spent in MVPA is not significantly lower in children and teenagers with limb fractures, it no longer reached the international recommendations for school-aged children (MVPA > 60 minutes), which may be interpreted as a lifestyle modification or a behavioural change to avoid new trauma.

LEVEL OF EVIDENCE

II.

Pediatric Distal Forearm Fracture Epidemiology in Malmö, Sweden-Time Trends During Six Decades

Background  The distal forearm fracture is the most common fracture in children. To allocate health care resources and evaluate if prevention strategies have been successful, it is essential to monitor changes in the epidemiology of common fractures. Methods  Our hospital serves a city in which year 2006 included 276,244 inhabitants (49,664 <17 years of age). Through the hospital archives, we identified fractures sustained by individuals younger than 16 years during 2005 and 2006 and compared these with previous collected and published data from the same area and hospital for the period 1950 to 1994. We used official population data to estimate period-specific fracture rates and age and gender standardized time trends. We report rates as number of fractures per 100,000 person-years and changes between periods as rate ratios (RR) with 95% confidence intervals (CIs). Results  We identified 521 distal forearm fractures, corresponding to a crude fracture incidence of 564/100,000 person-years (boys 719; girls 401). Age-adjusted fracture incidence was 70% higher in boys than in girls (RR 1.7; 95% CI 1.3-2.3). The age- and gender-adjusted hand fracture incidence was 40% higher in 2005-2006 than in 1950/1955 (RR 1.4; 95% CI 1.2 to 1.8) but no higher than 1993-1994 (RR 1.1; 95% CI 0.9-1.3). Fracture etiology of 2005 to 2006 included sports injuries in 41% and traffic accidents in 11% of the cases, while sports injuries explained 37% and traffic accidents 18% in 1950 to 1955. Conclusion  In 2005 to 2006, we found higher rates in boys and higher overall rates compared with the 1950s but no significant differences compared with the rates in 1993 to 1994. Future studies should include patient-specific data to unravel causal factors. Level of evidence  This is a Level III b study.

Hand fracture epidemiology and etiology in children-time trends in Malmö, Sweden, during six decades

BACKGROUND

The aim of this study was to describe hand fracture epidemiology/etiology in city children and describe time trend during six decades.

PATIENTS AND METHODS

A single hospital serves the entire city population of 271,271 (year 2005). Through the hospital medical and radiological archives, we collected epidemiology and etiology data concerning pediatric (age < 16 years) hand fractures in city residents, treated during 2005-2006. We compared these data to previously collected data in in the same city during 12 evaluated periods from 1950/1955 to 1993-1994. We present period-specific crude and age- and gender-adjusted fracture incidence rates and group differences as incidence rate ratios (RR) with 95% confidence intervals (95% CI).

RESULTS

In 2005-2006, we identified 414 hand fractures (303 in boys and 111 in girls), 247 phalangeal fractures (60% of all hand fractures), 140 metacarpal/carpal fractures (except the scaphoid bone) (34%), and 27 scaphoid fractures (6%). The crude hand fracture rate in children was 448/100,000 person years (639/100,000 in boys and 247/100,000 in girls), with a 2.5 times higher age-adjusted incidence in boys than in girls. Compared to 1950/1955, the age and gender-adjusted hand fracture incidence was twice as high in 2005-2006 and more than twice as high in 1976-1979. Compared to 1976-1979, we found no significant difference in the age and gender-adjusted hand fracture incidence in 2005-2006. In 2005-2006, sports injuries explained 42%, fights 20%, and traffic accidents 13% of the hand fractures. In 1950/1955, sports injuries explained 27% of fractures, fights 10%, and traffic accidents 21%.

CONCLUSIONS

The incidence of hand fractures in children was more than twice as high in the end of the 1970s compared to the 1950s, where after no significant change could be found. Also, fracture etiology has changed. New studies are needed, to adequately allocate health care resources and identify new fracture prone activities suitable for preventive measures.

LEVEL OF EVIDENCE

III.

Extended physical education in children aged 6-15 years was associated with improved academic achievement in boys

AIM

Physical activity (PA) has been associated with enhanced cognition, brain development and concentration. This study evaluated whether increased physical education (PE) improved academic achievement.

METHODS

We recruited 304 children (55% boys) from a Swedish school in Skane County in 1998-2002 when they were six to seven years of age and followed them through all nine mandatory school years. Their PE level was increased from 60 to 200 minutes per week, and their results were compared with 73 885 control children (51% boys) in the county who graduated in the same years and did the standard 60 minutes of PE per week. Their academic achievements were measured as their final grade scores and the proportion of students eligible for upper secondary school.

RESULTS

The eligibility for further education increased in the intervention boys by 6.8 percentage points and the mean grade score by 12.1 points, while in the control group as a whole, the eligibility rate decreased by 0.7 percentage points and the mean grade score increased by 1.7 points. No changes in eligibility rates or mean grade scores were seen in the intervention girls.

CONCLUSION

Increasing weekly PE over nine years was associated with improved academic achievement in boys.

Radiographic anatomy of the proximal femur: femoral neck fracture vs. transtrochanteric fracture

Objective

To evaluate the correlation between radiographic parameters of the proximal femur with femoral neck fractures or transtrochanteric fractures.

Methods

Cervicodiaphyseal angle (CDA), femoral neck width (FNW), hip axis length (HAL), and acetabular tear drop distance (ATD) were analyzed in 30 pelvis anteroposterior view X-rays of patients with femoral neck fractures (n = 15) and transtrochanteric fractures (n = 15). The analysis was performed by comparing the results of the X-rays with femoral neck fractures and with transtrochanteric fractures.

Results

No statistically significant differences between samples were observed.

Conclusion

There was no correlation between radiographic parameters evaluated and specific occurrence of femoral neck fractures or transtrochanteric fractures.

Low physical activity is related to clustering of risk factors for fracture-a 2-year prospective study in children

The study investigates the effect of physical activity (PA) on a composite score for fracture risk in pre-pubertal children. Low PA in children is related to the composite score for fracture risk and the pre-pubertal years seem to be a period when PA positively affects the score.

INTRODUCTION

This study evaluates if PA in children is related to clustering of risk factors for fracture. Research questions are the following: (i) What is the effect of physical activity (PA) on single traits and a composite score for fracture risk? (ii) Could this score be used to identify the level of PA needed to reach beneficial effects?

METHODS

This prospective population-based study included 269 children, aged 7-9 years at baseline while 246 attended the 2-year follow-up. We estimated duration of PA by questionnaires and measured traits that independently predict fractures. We then calculated gender specific Z-scores for each variable. The mean Z-score of all traits was used as a composite score for fracture risk. We tested correlation between duration of PA, each trait, and the composite score and group differences between children in different quartiles of PA.

RESULTS

At baseline, we found no correlation between duration of PA and any of the traits or the composite score. At follow-up, we found a correlation between PA and the composite score. Physical activity had an effect on composite score, and children in the lowest quartiles of PA had unbeneficial composite score compared to children in the other quartiles.

CONCLUSION

Low PA in children is related to clustering of risk factors for fracture, and the pre-pubertal years seem to be a period when PA positively affects the composite score.

Do bone mineral content and density determine fracture in children? A possible threshold for physical activity

BackgroundRelations between bone parameters, physical exertion, and childhood fractures are complex. We aimed to estimate the associations between fracture history and bone mineral content (BMC) and areal bone mineral density (aBMD) at 7 years of age, by levels of physical activity, as a proxy for trauma frequency.MethodsWe used data collected from 2,261 children of the Generation XXI birth cohort, assembled in 2005/6 in Porto, Portugal. At the age of 7 years (2012/4), fracture history, time spent per week in active play, and sports practice were reported by parents. Subtotal and lumbar spine (LS) BMC and aBMD were measured using whole-body dual-energy X-ray absorptiometry.ResultsBoys and girls in the highest categories of time spent in sports practice or active play generally had higher BMC and aBMD. Among girls, BMC and aBMD were protective of fracture only in the highest quarter of active play (>660 min/week)-odds ratios (OR; 95% confidence interval (95% CI)) for subtotal BMC=0.27 (0.11-0.67), subtotal aBMD=0.18 (0.06-0.49), and LS aBMD=0.41 (0.22-0.75). For boys in the highest quarter of sports practice (>240 min/week), subtotal and LS BMC were protective of fracture-OR=0.39 (0.16-0.98) and 0.51 (0.27-0.96), respectively.ConclusionIn prepubertal children, BMC and aBMD predicted fracture history only in the highest levels of physical activity.

Time trends in pediatric fracture incidence in Sweden during the period 1950-2006

Background and purpose - Pediatric fracture incidence may not be stable. We describe recent pediatric fracture epidemiology and etiology and compare this to earlier data. Patients and methods - The city of Malmö (population 271,271 in 2005) in Sweden is served by 1 hospital. Using the hospital diagnosis registry, medical charts, and the radiographic archive, we identified fractures in individuals <16 years that had occurred during 2005 and 2006. We also retrieved previously collected fracture data from between 1950 and 1994, from the hospital's pediatric fracture database. We used official population data to estimate period-specific fracture incidence (the number of fractures per 10⁵ person-years) and also age- and sex-adjusted incidence. Differences are reported as rate ratios (RRs) with 95% confidence intervals. Results - The pediatric fracture incidence during the period 2005-2006 was 1,832 per 10⁵ person-years (2,359 in boys and 1,276 in girls), with an age-adjusted boy-to-girl ratio of 1.8 (1.6-2.1). Compared to the period 1993-1994, age-adjusted rates were unchanged (RR =0.9, 95% CI: 0.8-1.03) in 2005-2006, with lower rates in girls (RR =0.8, 95% CI: 0.7-0.99) but not in boys (RR =1.0, 95% CI: 0.9-1.1). We also found that the previously reported decrease in unadjusted incidence in Malmö from 1976-1979 to 1993-1994 was based on changes in demography, as the age-adjusted incidences were similar in the 2 periods (RR =1.0, 95% CI: 0.9-1.1). Interpretation - In Malmö, pediatric fracture incidence decreased from 1993-1994 to 2005-2006 in girls but not in boys. Changes in demography, and also other factors, influence the recent time trends.

How does a physical activity programme in elementary school affect fracture risk? A prospective controlled intervention study in Malmo, Sweden

OBJECTIVES

Recent evidence from the 7-year follow-up of the Pediatric Osteoporosis Prevention (POP) study indicates an inverse correlation between years of participation in a physical activity (PA) intervention and fracture risk in children. However, we could not see a statistically significant reduction in fracture risk, which urged for an extension of the intervention.

SETTING

The study was conducted in 4 neighbouring elementary schools, where 1 school functioned as intervention school.

PARTICIPANTS

We included all children who began first grade in these 4 schools between 1998 and 2012. This resulted in 1339 children in the intervention group and 2195 children in the control group, all aged 6-8 years at the state of the study.

INTERVENTION

We launched an 8-year intervention programme with 40 min of moderate PA per school day, while the controls continued with the Swedish national standard of 60 min of PA per week.

PRIMARY OUTCOME MEASURE

We used the regional radiographic archive to register objectively verified fractures and we estimated annual fracture incidences and incidence rate ratios (IRRs).

RESULTS

During the first year after initiation of the intervention, the fracture IRR was 1.65 (1.05 to 2.08) (mean 95% CI). For each year of the study, the fracture incidence rate in the control group compared with the intervention group increased by 15.7% (5.6% to 26.8%) (mean 95% CI). After 8 years, the IRR of fractures was 52% lower in the intervention group than in the control group (IRR 0.48 (0.25 to 0.91) (mean 95% CI))].

CONCLUSIONS

Introduction of the school-based intervention programme is associated with a higher fracture risk in the intervention group during the first year followed by a gradual reduction, so that during the eighth year, the fracture risk was lower in the intervention group.

TRIAL REGISTRATION NUMBER

NCT00633828.

Bone Traits Seem to Develop Also During the Third Decade in Life-Normative Cross-Sectional Data on 1083 Men Aged 18-28 Years

By identifying individuals with low peak bone mass (PBM) at young age, early targeted interventions to reduce future fracture risk could be possible. Peripheral quantitative computed tomography (pQCT) is in many ways superior to the gold standard dual-energy X-ray absorptiometry (DXA), as cortical and trabecular compartments as well as the volumetric density and bone structure can be examined separately. Because each of these traits contributes independently to bone strength, it is probable that pQCT provides an even better fracture risk estimation than DXA. Currently, the clinical applications of pQCT are limited partly because comprehensive normative pQCT data, especially in young men, are not readily available. We therefore set up a study in young men with the following objectives: (1) to identify peak ages in pQCT bone traits with special reference to PBM and peak bone strength; and (2) to provide normative pQCT data. We measured volumetric bone mineral density and structural parameters at ultradistal (trabecular bone) and diaphyseal radius and tibia (cortical bone) by pQCT scans (Stratec XCT2000®; Stratec Medizintechnik GmbH, Pforzheim, Germany) in a population-based age-stratified sample of 1083 men aged 18-28 yr residing in greater Malmö, Sweden. Group differences in 1-yr classes were evaluated by analysis of variance. We found similar bone traits in age groups at ultradistal sites whereas most bone traits at diaphyseal sites were higher with higher ages, however with different increment patterns depending on the specific trait. In Swedish young adult men, we found that different bone traits continued to change after age 18, but at different rates, indicating that peak areal bone mineral density (as measured by DXA) and peak bone strength may be reached at different ages.

Effects of an 8-year childhood physical activity intervention on musculoskeletal gains and fracture risk

BACKGROUND

Physical activity (PA) in childhood is associated with musculoskeletal benefits while the effect on fracture risk is yet to be determined. The aim of this study was to evaluate whether extension of a PA intervention leads to improvement in musculoskeletal traits with an accompanied reduced fracture risk. We hypothesized that the PA program would have beneficial effects in both sexes, but more so in girls since they tend to be less physically active than boys during this time frame.

METHODS

In one elementary school we increased physical education (PE) from 60 to 200min per school week and followed 65 girls and 93 boys from a mean age of 7years until a mean age of 15years. Thirty-nine girls and 37 boys in three other schools continued with 60min of PE per week during the same years and served as controls. We measured bone mineral content (BMC), areal bone mineral density (aBMD), and bone area annually with dual energy X-ray absorptiometry, and leg muscle strength with a computerized dynamometer. In 3534 children within the same PE program (1339 in the intervention and 2195 in the control group) we registered incident fractures during the 8-year study period and estimated annual sex-specific fracture incidence rate ratios (IRRs).

RESULTS

Girls in the intervention group annually gained more total body less head aBMD, spine aBMD (p<0.01), femoral neck BMC (p<0.05), lumbar vertebrae size (p<0.05), and knee flexion strength (p<0.05) than girls in the control cohort. In boys we found no group differences. There was an inverse correlation between number of years with extra PE and the annual IRR of sustaining fractures in both girls (r=-0.90 (95% CI -0.98 to -0.51); p<0.001) and boys (r=-0.74 (95% CI -0.94 to -0.02); p<0.05).

CONCLUSION

In this 8-year pediatric school-based moderate exercise intervention program there is an inverse correlation in both sexes between annual IRR and each additional year of extra PA. A sub-cohort of girls in the intervention group had greater gains in bone mass, bone size, and muscle strength, which could possibly explain the inverse correlation between years within the PA program and fracture risk, while in boys the reason for the inverse correlation remains unknown. It should be noted that differences in unreported factors such as skeletal maturity status, diet, and spare time PA could confound our inferences. That is, true causality cannot be stated.

Fracture Risk in Relation to Serum 25-Hydroxyvitamin D and Physical Activity: Results from the EPIC-Norfolk Cohort Study

Vitamin D deficiency and physical inactivity have been associated with bone loss and fractures, but their combined effect has scarcely been studied either in younger or older adults. Therefore, we aimed to assess the associations between physical activity, age and 25-hydroxyvitamin D (25(OH)D) status separately and in combination with the incidence of fracture risk in the EPIC-Norfolk cohort study. Baseline (1993-1998) self-reported physical activity and serum 25(OH)D concentrations at follow-up (1998-2000) were collected in 14,624 men and women (aged 42-82 y between 1998 and 2000). Fracture incidence was ascertained up to March 2015. Cox proportional hazard model was used to determine HRs of fractures by plasma 25(OH)D (<30, 30 to <50, 50 to <70, 70 to <90, >90 nmol/L), age (<65 y and >65 y) and physical activity (inactive and active) categories, by follow-up time per 20 nmol/L increase in serum 25(OH)D and to explore age-25(OH)D and physical activity-25(OH)D interactions. The age-, sex-, and month-adjusted HRs (95% CIs) for all fractures (1183 fractures) by increasing vitamin D category were not significantly different. With additional adjustment for body mass index, smoking status, alcohol intake, supplement use and history of fractures, the fracture risk was 29% lower in those participants with 50 to 70 nmol/L compared with those in the lowest quintile (<30 nmol/L). Physical inactivity based on a single baseline assessment was not associated with fracture risk. Vitamin D status appeared inversely related to fractures in middle aged adults. In older adults, the relationship between vitamin D status and fracture risk was observed to be J-shaped. Clinical and public health practice in vitamin D supplementation could partially explain these findings, although definitive conclusions are difficult due to potential changes in exposure status over the long follow up period.

No difference in the level of physical activity between children who have or have never sustained a fracture

This study investigates whether children with an acute fracture have a different level of physical activity compared to children who have never sustained a fracture, as measured by the Physical Activity Questionnaire for older children (PAQ-C). The PAQ-C scores of 683 children (295 girls) aged 6-12 years (mean age 9.4 years) who presented to our institution with an acute fracture were compared to the PAQ-C scores of 151 random children (81 girls) aged 6-12 years (mean 9.1 years) in the same area who had never sustained a fracture. Multivariate regression analysis was employed, controlling for age and gender. The mean PAQ-C score of the children who presented to the institution with an acute fracture was 2.85 (95% confidence interval [CI], 2.80-2.91). For the children who had never sustained a fracture, the mean PAQ-C score was 2.78 (95% CI, 2.69-2.87). If there is a true difference in the level of physical activity between children who have or have never sustained a fracture, the PAQ-C questionnaire is not sensitive enough to identify it.

A seven-year physical activity intervention for children increased gains in bone mass and muscle strength

AIM

This study evaluated the musculoskeletal effects of increased physical activity on children, starting at six to nine years of age.

METHODS

In one school we increased the physical education of 72 girls and 100 boys to 200 minutes per week over seven years. In three other schools, 45 girls and 47 boys continued to receive 60 minutes per week. We measured areal bone mineral density (aBMD) with dual energy X-ray absorptiometry and muscle strength with computerised dynamometer at baseline and after seven years and tibial cortical thickness with peripheral quantitative computed tomography after seven years.

RESULTS

Girls in the intervention group gained 0.04 g/cm(2) (0.01-0.08) more total spine aBMD (p < 0.05) and 6.2Nm (1.6, 10.7) more knee flexion strength (p < 0.01) than control group girls and had a 0.1 mm (0.0, 0.3) higher tibial cortical thickness at follow-up (p < 0.05). Boys in the intervention group gained 7.3Nm (0.4, 14.2) more knee extension strength (p < 0.05) and 7.4Nm (2.3, 12.4) more knee flexion strength (p < 0.01) than the control group boys, but their aBMD was no higher than the control group.

CONCLUSION

A seven-year, population-based moderately intense exercise intervention enhanced gains in spine bone mass in girls and knee muscle strength in both genders.

Increasing wrist fracture rates in children may have major implications for future adult fracture burden

Background and purpose - Childhood fractures are associated with lower peak bone mass (a determinant of osteoporosis in old age) and higher adult fracture risk. By examining time trends in childhood fracture epidemiology, it may be possible to estimate the vector of fragility fracture risk in the future. Patients and methods - By using official inpatient and outpatient data from the county of Skåne in Sweden, 1999-2010, we ascertained distal forearm fractures in children aged ≤ 16 years and estimated overall and age- and sex-specific rates and time trends (over 2.8 million patient years) and compared the results to earlier estimations in the same region from 1950 onwards. Results - During the period 1999-2010, the distal forearm fracture rate was 634 per 10(5) patient years (750 in boys and 512 in girls). This was 50% higher than in the 1950s with a different age-rate distribution (p < 0.001) that was most evident during puberty. Also, within the period 1999-2010, there were increasing fracture rates per 10(5) and year (boys +2.0% (95% CI: 1.5-2.6), girls +2.4% (95% CI: 1.7-3.1)). Interpretation - The distal forearm fracture rate in children is currently 50% higher than in the 1950s, and it still appears to be increasing. If this higher fracture risk follows the children into old age, numbers of fragility fractures may increase sharply-as an upturn in life expectancy has also been predicted. The origin of the increase remains unknown, but it may be associated with a more sedentary lifestyle or with changes in risk behavior.