Roope Parviainen

Background: Trampoline use has become increasingly common among children and adolescents, paralleled by a rise in trampoline-related injuries. Nevertheless, current age-based recommendations for trampoline use are supported by limited evidence. This study aimed to determine whether the frequency and severity of trampoline-related fractures differ among specific pediatric age groups. Methods: We identified all pediatric trampoline-related fractures treated in the Helsinki area, Finland, between 2014 and 2022. Cases were extracted from the institutional fracture registry, the KIDS Fracture Tool, which contained 18,279 fractures as of December 2022. The distribution, fracture severity, and frequency of surgical treatment were compared with the other sports-related fractures recorded in the registry. Trampoline-related fractures were analyzed across 3 age groups: 0 to 5 years, 6 to 10 years, and 11 to 15 years. Results: A total of 1153 trampoline-related fractures were identified (592 in girls and 561 in boys), representing 6.3% of all pediatric fractures. The annual incidence of trampoline-related fractures was 9.3 per 10,000 children. In the youngest age group, the lower leg was the most commonly fractured site, whereas forearm fractures predominated in the older groups. Well-aligned fracture was the most frequent fracture pattern in younger children, while more severe fracture types increased in prevalence with age. The proportion of open fractures was higher in the trampoline cohort than in the overall sport-related fracture cohort (relative risk, 2.02; 95% CI: 1.22-3.34). Conclusions: Trampoline-related fractures show age-dependent variation, with younger children sustaining predominantly low-energy injuries and older children experiencing more severe fracture patterns. Trampoline injuries were associated with a higher risk of displaced fractures requiring internal fixation and open fractures. Due to the lack of exposure data, definitive conclusions cannot be made regarding age-specific injury risk or age-based restrictions. Level of Evidence: Level IV—case series.

Conditions during gestation, such as maternal smoking, may affect offspring's bone structure. This could increase the offspring's risk of bone fractures during childhood. In this study, we aimed to assess the association between prenatal exposure to maternal smoking and childhood bone fracture risk. We used a register-based birth cohort that included all children born in Finland between January 1987 and September 1990. After exclusions, the final study population consisted of 220,699 persons. Using a unique national identification number, we linked the cohort data to the fracture diagnosis in specialty care and covariate data using the Medical Birth Register (MBR), Statistics Finland and Care Register for Health Care (CRHC). The fractures were analyzed in three groups: all fractures, non-high-energy fractures, and high-energy fractures. The analyses were adjusted for sex, parity, child's year of birth, mother's age at childbirth, mother's and father's educational level, and mother's fracture status. We tested the association in three age groups: <1 year, 1–<5 years, and 5–<15 years using Cox and (recurrent fractures) Poisson regression. A total of 18,857 (8.5%) persons had at least one bone fracture diagnosis before the age of 15 years. In the age group 5–<15 years, maternal smoking during pregnancy was associated with higher fracture risk in all of the studied fracture groups: hazard ratio (HR) = 1.12 (95% confidence interval [CI] 1.06–1.17) in all fractures, 1.13 (95% CI 1.07–1.19) in non-high-energy, and 1.15 (95% CI 1.00–1.32) in high-energy fractures. There were no significant associations in other age groups in any of the fracture groups. No statistically significant association between maternal smoking during pregnancy and offspring's risk of recurrent fractures was found. In conclusion, 5- to 15-year-olds whose mothers have smoked during pregnancy have an increased risk of bone fractures treated in specialty care. © 2023 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

The understanding of the biological and environmental risk factors of fractures in pediatrics is limited. Previous studies have reported that fractures involve heritable traits, but the genetic factors contributing to the risk of fractures remain elusive. Furthermore, genetic influences specific to immature bone have not been thoroughly studied. Therefore, the aim of the present study was to identify genetic variations that are associated with fractures in early childhood. The present study used a prospective Northern Finland Birth Cohort (year 1986; n=9,432). The study population was comprised of 3,230 cohort members with available genotype data. A total of 48 members of the cohort (1.5%) had in‑hospital treated bone fractures during their first 6 years of life. Furthermore, individuals without fracture (n=3,182) were used as controls. A genome‑wide association study (GWAS) was performed using a frequentist association test. In the GWAS analysis, a linear regression model was fitted to test for additive effects of single‑nucleotide polymorphisms (SNPs; genotype dosage) adjusting for sex and performing population stratification using genotypic principal components. Using the GWAS analysis, the present study identified one locus with a significant association with fractures during childhood on chromosome 10 (rs112635931) and six loci with a suggested implication. The lead SNP rs112635931 was located near proline‑ and serine‑rich 2 (PROSER2) antisense RNA 1 (PROSER2‑AS1) and PROSER2, thus suggesting that these may be novel candidate genes associated with the risk of pediatric fractures.