Background Although femur fractures in children are rare, they are the most common fractures in need of hospitalization. We sought to describe the epidemiology and treatment of pediatric femur fractures recorded in the Swedish Fracture Register (SFR). We also studied the relationship between femur fractures, age, sex, fracture pattern, injury mechanism, seasonal variation and treatment. Methods This nationwide observational register study was based on the pediatric part of the SFR. We included all patients < 16 years of age who were registered in the SFR from 2015 to 2018. Results Of the 709 femur fractures, 454 (64%) occurred in boys. Sixty-two of these fractures were proximal (9%), 453 shaft (64%) and 194 distal (27%). A bimodal age distribution peak was observed in boys aged 2–3 and 16–19 years. In contrast, the age distribution among girls was evenly distributed. Younger children were mainly injured by a fall, whereas older children sustained their fracture because of traffic accidents. Non-surgical treatment prevailed among younger children; however, prevalence of surgical treatment increased with age. Conclusions We found a lower ratio between boys and girls (1.8:1) compared to earlier studies. The bimodal age distribution was seen only in boys. Falls were the most common injury in younger children, whereas traffic-related accidents were the most common in adolescents. With age, there was a corresponding increase in surgical treatment.

Background and purpose Hyperactive behavior pattern (such as attention deficit hyperactivity disorder (ADHD)) is proposed to be present in individuals with Legg-Calvé-Perthes disease (LCPD). We investigated whether individuals with LCPD have a higher risk of ADHD, depression, and mortality.Subjects and methods We identified 4,057 individuals with LCPD in Sweden during the period 1964–2011. 40,570 individuals without LCPD were randomly selected from the Swedish general population and matched by year of birth, sex, and region (control group). We used Cox proportional hazard regression to estimate the relative risks.Results Compared to the control group, individuals with LCPD had a raised hazard ratio (HR) of 1.5 (95% CI: 1.2–1.9) for ADHD. The risks were higher for female individuals (HR = 2.1, CI: 1.3–3.5) than for male individuals (HR = 1.4, CI: 1.1–1.8). Individuals with LCPD had a modestly higher hazard ratio for depression (HR = 1.3, CI: 1.1–1.5) than the control group. Furthermore, individuals with LCPD had a slightly higher mortality risk than the control group (HR = 1.2, CI: 1.0–1.4)Interpretation Individuals with LCPD have a higher risk of ADHD. Hyperactivity could expose the femoral head to higher mechanical stress and contribute to the etiology of LCPD. The higher risk of depression may be due to the burden of LCPD itself or could reflect neurobehavioral aspects of ADHD changing into depression later in life. Individuals with LCPD have a higher mortality risk, with higher risk of suicide and cardiovascular diseases.

OBJECTIVE:We hypothesized that patients with Legg--Calvé--Perthes disease (LCPD) might have higher risks of cardiovascular and blood diseases. METHODS: A total of 2579 patients with LCPD diagnosed between 1965 and 2005 were identified with the Swedish Inpatient Register. A total of 13748 individuals without LCPD were selected randomly from among the Swedish general population, with matching according to year of birth, age, gender, and region of residence. Cox proportional--hazard regression analyses, with adjustment for socioeconomic index, were used to estimate relative risks. The patients also were compared with their same--gender siblings. RESULTS: Patients with LCPD had a hazard ratio (HR) of 1.70 (95% confidence interval [CI]: 1.48 -1.95) for cardiovascular diseases, compared with individuals without LCPD. There were statistically significantly higher risks for hypertensive disease, ischemic heart diseases, cerebrovascular diseases, diseases of arteries, veins, and lymphatic vessels. There were statistically significantly higher risks for blood diseases, including anemias and coagulation defects (HR: 1.94 [95% CI: 1.51-2.49]), which were more pronounced among subjects >30 years of age at the follow--up (HR: 2.45 [95% CI: 1.77-3.41]). Patients also had statistically significantly higher risks of nutritional anemia (HR: 2.32 [95% CI: 1.41 -3.81]) and hemolytic anemia ). Analyses using siblings as the comparison group showed consistent results for cardiovascular diseases. CONCLUSION:The results are consistent with the hypothesis that an insufficient blood supply to the femoral head, attributable to vascular pathologic conditions, is involved in the pathogenesis of LCPD.

Human multiple synostoses syndrome 3 is an autosomal dominant disorder caused by pathogenic variants in FGF9. Only two variants have been described in FGF9 in humans so far, and one in mice. Here we report a novel missense variant c.566C > G, p.(Pro189Arg) in FGF9. Functional studies showed this variant impairs FGF9 homodimerization, but not FGFR3c binding. We also review the findings of cases reported previously and report on additional features not described previously.

Level III, prognostic study.

A retrospective study, level II.

Background and purpose Previous studies have suggested that Legg-Calvé-Perthes disease (LCPD) is associated with repetitive trauma, coagulation problems and anatomical abnormalities of the blood supply to the femoral head. The hypothesis that repetitive trauma can affect the blood supply of the femoral head, leading to LCPD, is supported by an animal model. For evidence of an increased risk of repetitive trauma, we investigated whether patients with LCPD have a higher risk for severe injuries requiring hospitalization.Patients and methods We identified 2579 patients with LCPD in Sweden during the period 1964–2005. 13,748 individuals without LCPD were randomly selected from the Swedish general population, matched by year of birth, sex and region (control group). Cox proportional hazard regression estimated the risks.Results Compared to the control group, patients with LCPD had a modestly raised hazard ratio (HR) of 1.2 (95% CI 1.1–1.3) for injury requiring hospitalization. The risks were slightly higher for soft tissue injuries (HR = 1.3, 95% CI:1.1–1.4) than for fractures (HR = 1.1, 95% CI: 1.0–1.3) and more pronounced among females. Compared to the control group, the higher risk for injury only applied to the lower extremities (HR = 1.2, 95% CI: 1.0–1.4) in patients with LCPD.Interpretation Patients with LCPD are vulnerable to injuries which could be interpreted as a marker of hyperactive behavior. It could also implicate that anatomical changes in the bone formation or blood supply of the femoral head – increasing its sensibility for trauma – contribute to the etiology of LCPD.

Background Most fractures in children are fractures of the upper extremity. Proximal and diaphyseal humeral fractures account for a minority of these fractures. To our knowledge, few previous reports address these fractures. This study aimed to describe the epidemiology and current treatment of proximal and diaphyseal humeral fractures by using the Swedish Fracture Register (SFR). Methods In this nationwide observational study from the SFR we analysed data on patient characteristics, injury mechanism, fracture classification and treatment. We included patients aged < 16 years at time of injury with proximal or diaphyseal humeral fracture registered in 2015–2019. Results 1996 (1696 proximal and 300 diaphyseal) fractures were registered. Proximal fractures were more frequent in girls whereas diaphyseal fractures were more frequent in boys. The median age at fracture was 10 years in both fracture types but patient’s age was more widespread in diaphyseal fracture (IQR 5–13 compared to IQR 7–12 in proximal). In both sexes, the most registered injury mechanism was fall. Horse-riding was a common mechanism of injury in girls, whereas ice-skating and skiing were common mechanisms in boys. Most proximal fractures were metaphyseal fractures. Most diaphyseal fractures were simple transverse or oblique/spiral fractures. The majority of fractures were treated non-surgically (92% of proximal and 80% of diaphyseal fractures). The treatment method was not associated with the patient’s sex. Surgery was more often performed in adolescents. The most common surgical methods were K-wire and cerclage fixation in proximal fracture and intramedullary nailing in diaphyseal fracture. Conclusion Following falls, we found sex-specific sport activities to cause most proximal and diaphyseal paediatric fractures. Further studies on prophylactic efforts in these activities are needed to investigate whether these fractures are preventable. The majority of the fractures were treated non-surgically, although surgical treatment increased with increasing age in both sexes. Trial registration Not applicable. The present study is a register-based cohort study. No health care intervention had been undertaken.