Childhood obesity as a risk factor for bone fracture: a mechanistic study

Is Adolescent Obesity Associated With a Higher Risk for Pelvic Fractures in Motor Vehicle Collisions?

INTRODUCTION

The impact of obesity on the incidence of blunt pelvic fractures in adults is unclear, and adolescents may have an increased risk of fracture due to variable bone mineral density and leptin levels. Increased subcutaneous adipose tissue may provide protection, though the association between obesity and pelvic fractures in adolescents has not been studied. This study hypothesized that obese adolescents (OAs) presenting after motor vehicle collision (MVC) have a higher rate of pelvic fractures, and OAs with such fractures have a higher associated risk of complications and mortality compared to non-OAs.

METHODS

The 2017-2019 Trauma Quality Improvement Program database was queried for adolescents (12-16 y old) presenting after MVC. The primary outcome was a pelvic fracture. Adolescents with a body mass index ≥30 (OA) were compared to adolescents with a body mass index <30 (non-OA). Subgroup analyses for high-risk and low-risk MVCs were performed. Multivariable logistic regression analyses were also performed adjusting for age and sex.

RESULTS

From 22,610 MVCs, 3325 (14.7%) included OAs. The observed rate of pelvic fracture was similar between all OA and non-OA MVCs (10.2% versus 9.4%, P = 0.16), as well as subanalyses of minor or high-risk MVC (both P > 0.05). OAs presenting with a pelvic fracture after high-risk MVC had a similar risk of complications, pelvic surgery, and mortality compared to non-OAs (all P > 0.05). However, OAs with a pelvic fracture after minor MVC had a higher associated risk of complications (OR 2.27, CI 1.10-4.69, P = 0.03), but a similar risk of requiring pelvic surgery, and mortality (all P > 0.05).

CONCLUSIONS

This national analysis found a similar observed incidence of pelvic fractures for OAs versus non-OAs involved in an MVC, including subanalyses of minor and high-risk MVC. Furthermore, there was no difference in the associated risk of morbidity and mortality except for OAs involved in a minor MVC had a higher risk of complication.

Childhood Obesity: An Updated Review

BACKGROUND

Childhood obesity is an important and serious public health problem worldwide.

OBJECTIVE

This article aims to familiarize physicians with the evaluation, management, and prevention of childhood.

METHODS

A PubMed search was conducted in May, 2021, in Clinical Queries using the key terms "obesity" OR "obese". The search included clinical trials, randomized controlled trials, case-control studies, cohort studies, meta-analyses, observational studies, clinical guidelines, case reports, case series, and reviews. The search was restricted to English literature and children. The information retrieved from the above search was used in the compilation of the present article.

RESULTS

Most obese children have exogenous obesity characterized by a growth rate for height above the 50th percentile, normal intelligence, normal genitalia, and lack of historical or physical evidence of an endocrine abnormality or a congenital syndrome. Obese children are at risk for dyslipidemia, hypertension, diabetes mellitus, non-alcoholic fatty liver disease, obstructive sleep apnea, psychosocial disturbances, impaired quality of life, and shorter life expectancy. The multitude of serious comorbidities necessitates effective treatment modalities. Dietary modification, therapeutic exercise, and behavioral modification are the fundamentals of treatment. Pharmacotherapy and/or bariatric surgery should be considered for obese individuals who do not respond to the above measures and suffer from a serious comorbid condition.

CONCLUSION

Childhood obesity, once established, is often refractory to treatment. Most treatment programs lead to a brief period of weight loss, followed by rapid re-accumulation of the lost weight after the termination of therapy. As such, preventive activity is the key to solving the problem of childhood obesity. Childhood obesity can be prevented by promoting a healthy diet, regular physical activity, and lifestyle modification. Parents should be encouraged to get involved in school and community programs that improve their children's nutritional status and physical activity.

Navigating Challenges and Treatment Options in Diaphyseal Forearm Fractures Among Adolescents: Case Series and Narrative Review

In this paper, we recount the medical trajectories of two male patients, both fourteen years of age, who sustained re-fractures of their radius and ulna six months post their primary diaphyseal fractures. Owing to the limited capacity for growth of the forearm bones between the ages of ten to sixteen years, many queries are engendered concerning apt treatment strategies. The pressing questions are whether these should be conservative or surgical and the precise method to be employed in surgical interventions. This discourse endeavors to demarcate preferred therapeutic options and shed light on a series of standard clinical dilemmas physicians encounter, along with an exhaustive scrutiny of existing literature.

Pediatric obesity-Long-term consequences and effect of weight loss

Childhood obesity is, according to the WHO, one of the most serious challenges of the 21st century. More than 100 million children have obesity today. Already during childhood, almost all organs are at risk of being affected by obesity. In this review, we present the current knowledge about diseases associated with childhood obesity and how they are affected by weight loss. One major causative factor is obesity-induced low-grade chronic inflammation, which can be observed already in preschool children. This inflammation-together with endocrine, paracrine, and metabolic effects of obesity-increases the long-term risk for several severe diseases. Type 2 diabetes is increasingly prevalent in adolescents and young adults who have had obesity during childhood. When it is diagnosed in young individuals, the morbidity and mortality rate is higher than when it occurs later in life, and more dangerous than type 1 diabetes. Childhood obesity also increases the risk for several autoimmune diseases such as multiple sclerosis, Crohn's disease, arthritis, and type 1 diabetes and it is well established that childhood obesity also increases the risk for cardiovascular disease. Consequently, childhood obesity increases the risk for premature mortality, and the mortality rate is three times higher already before 30 years of age compared with the normal population. The risks associated with childhood obesity are modified by weight loss. However, the risk reduction is affected by the age at which weight loss occurs. In general, early weight loss-that is, before puberty-is more beneficial, but there are marked disease-specific differences.

Load-to-strength ratio at the radius is higher in adolescent and young adult females with obesity compared to normal-weight controls

BACKGROUND

Among adolescents with extremity fractures, individuals with obesity have greater representation compared with individuals of normal-weight, despite having higher areal and volumetric bone mineral density (aBMD, vBMD) than their normal-weight counterparts. The relative increase in BMD in individuals with obesity may thus be insufficient to support the greater force generated upon falling. The load-to-strength ratio is a biomechanical approach for assessing the risk of fracture by comparing applied force to bone strength, with higher load-to-strength ratios indicating higher fracture risk.

OBJECTIVE

To assess the load-to-strength ratio at the distal radius in adolescent and young adult females with severe obesity (OB) compared with normal-weight healthy controls (HC). We hypothesized that OB have a higher load-to-strength ratio compared to HC.

METHODS

We examined bone parameters in 65 girls 14-21 years old: 33 OB and 32 HC. We used dual-energy X-ray absorptiometry (DXA) to assess body composition, high resolution peripheral quantitative CT (HR-pQCT) to estimate vBMD, and microfinite element analysis (μFEA) to assess bone strength at the distal radius. To quantify fracture risk, we computed the load-to-strength ratio, where the numerator is defined as the load applied to the outstretched hand during a forward fall and the denominator is the bone strength, as estimated by μFEA.

RESULTS

Although OB had higher total vBMD than HC (368.3 vs. 319.9 mgHA/cm3, p = 0.002), load-to-strength ratio at the radius was greater in OB than HC after controlling for age and race (0.66 vs. 0.54, p < 0.0001). In OB, impact force and load-to-strength ratio were associated negatively with % lean mass (r = -0.49; p = 0.003 and r = -0.65; p < 0.0001 respectively) and positively with visceral fat (r = 0.65; p < 0.0001 and r = 0.36; p = 0.04 respectively).

CONCLUSIONS

Adolescent and young adult females with obesity have higher load-to-strength ratio at the distal radius due to higher forces applied to bone in a fall combined with incomplete adaptation of bone to increasing body weight. This is differentially affected by lean mass, fat mass, and visceral fat mass.

Fracture incidence in children and adolescents 0-19 years old in Mexico: a 12-year cross-sectional analysis

The objective was to know the behavior of fractures in Mexican children and adolescents. According to our study, fractures in Mexican male children and adolescents seem to be decreasing; however, we still need more national studies to know the possible causes of these fractures.

PURPOSE

To describe the trends of fractures in Mexican children and adolescents across a 12-year period (2007 to 2019), and to analyze if these trends have changed over time between sexes and age groups.

METHODS

We identified all fracture cases registered in children and adolescents (0 to 19 years) at the emergency rooms and surgical departments of the Mexican Institute of Social Security between January 2007 and December 2019. We used ICD-10 to classify the fractures. The population was divided into two age groups: children (0 to 9 years) and adolescents (10 to 19 years). Additional information regarding sex and age was gathered up as well. We calculated annual incidence; incidence rates are presented per 10,000 population at risk. Changes in fracture trends were calculated using the average annual percentage change (AAPC).

RESULTS

Over 12 years, 1,400,443 fractures were registered. The most frequent site of fracture was forearm in 37.1% followed by shoulder (18.1%). The overall rates of fractures have remained similar over 12 years (86.5, IQR 81.0-94.2); however, a significant decrease in fractures was observed the last 3 years (2017-2019). According to the AAPC, only in men, in both age groups, a significant decrease in fractures was observed.

CONCLUSION

This is the first study in Mexico to follow the behavior of fractures in the pediatric population over 12 years. Fractures seem to be decreasing in children and adolescents. An epidemiological follow-up of childhood fractures is necessary to understand the causes of fractures to generate better prevention and treatment strategies.

Bone matrix quality in a developing high-fat diet mouse model is altered by RAGE deletion

Overweightness and obesity in adolescents are epidemics linked to chronic low-grade inflammation and elevated fracture risk. The increased fracture risk observed in overweight/obese adolescence contrasts the traditional concept that high body mass is protective against fracture, and thus highlights the need to determine why weight gain becomes detrimental to fracture during growth and maturity. The Receptor for Advanced Glycation End products (RAGE) is a central inflammatory regulator that can influence bone metabolism. It remains unknown how RAGE removal impacts skeletal fragility in overweightness/obesity, and whether increased fracture risk in adolescents could result from low-grade inflammation deteriorating bone quality. We characterized the multiscale structural, mechanical, and chemical properties of tibiae extracted from adolescent C57BL/6J (WT) and RAGE null (KO) mice fed either low-fat (LF) or high-fat (HF) diet for 12 weeks starting at 6 weeks of age using micro-computed tomography, strength, Raman spectroscopy, and nanoindentation. Overweight/obese WT HF mice possessed degraded mineral-crystal quality and increased matrix glycoxidation in the form of pentosidine and carboxymethyl-lysine, with HF diet in females only showing reduced cortical surface expansion and TMD independently of RAGE ablation. Furthermore, in contrast to males, HF diet in females led to more material damage and plastic deformation. RAGE KO mitigated glycoxidative matrix accumulation, preserved mineral quantity, and led to increased E/H ratio in females. Taken together, these results highlight the complex, multi-scale and sex-dependent relationships between bone quality and function under overweightness, and identifies RAGE-controlled glycoxidation as a target to potentially preserve matrix quality and mechanical integrity.

Bone health in adolescence

Adolescence is a fundamental period for the formation of the skeleton, because is the stage in which bones grow more in both size and strength, laying a solid foundation for the future health of the skeleton. Any condition interfering with optimal peak bone mass accrual can increase fracture risk later in life. Up to 80% of peak bone mass is genetically determined while the remaining 20% is modulated by environmental factors that, if deleterious, may result in low bone mineral density (BMD) and an increased risk of fracture. The preferred test to assess bone health is dual-energy x-ray absorptiometry (spine or total body less head) using Z scores instead of T scores, even though in short stature or growth delay, should be used the height Z-score. The correction of risk factors is the first treatment for low BMD in children and adolescents. It's necessary having a correct lifestyle for preserving bone health: a proper nutrition, an adequate physical weight-bearing activity and avoidance of alcohol intake and tobacco smoke. Bisphosphonates could be used in children who sustained osteoporotic fractures, impairing quality of life, when spontaneous recovery is low for the persistence of osteoporosis risk factors. This clinical review discusses factors affecting bone health during childhood and adolescence and deals with diagnosis and treatment of low bone mass or osteoporosis in this age group.

Prediction of fracture initiation and propagation in pelvic bones

The objective is developing an XFEM model that is capable of predicting different types of fracture in the pelvic bone under various loading conditions. Previously published mechanical and failure characteristics of cortical and cancellous tissues were implemented and assigned to an intact pelvic bone with specified cortical and cancellous tissues. Various loading conditions, including combined load directions, were applied to the acetabulum to model different types of fracture (e.g., anterior/posterior wall fracture and transverse fracture) in the pelvic bone. The predicated types of fracture and the maximum force at fracture were compared to those acquired from previously published experimental tests. Anterior/posterior wall fracture and transverse fracture were the most common types of fractures determined in the simulations. The XFEM simulations were able to predict similar fractures to those reported in the experimental tests. The maximum fracture force in the XFEM model was found to be 18.6 kN compared to 8.85 kN reported in the previous experimental tests. The results revealed that different types of fracture in the pelvic bones can be caused by the various loading conditions in unstable high-rate impact loads. Using proper mechanical and failure behaviors of cortical and cancellous tissues, XFEM modeling of pelvic bone is capable of predicting bone fracture. In future work, the XFEM models of cancellous and cortical tissues can be assigned to other bones in human body skeleton so that the failure mechanism in such bones can be investigated.

Mechanoadaptation of the bones of mice with high fat diet induced obesity in response to cyclical loading

An upward trend in childhood obesity implies a great need to determine its effects, both immediate and long-term. Obesity is osteoprotective in adults, but we know very little about the effects of obesity on the growing skeleton, particularly its ability to adapt to load. The objective of this research is to assess bone mechanoadaptation in adolescent obese mice. Ten mice were fed a high-fat diet (HFD) from 4 to 16 weeks of age, while a control group of the same size received a normal diet (ND). At 14 weeks of age, right tibiae were cyclically loaded with a 12 N peak load for HFD mice and a 9 N peak load for ND mice three times a week for two weeks, resulting in equal peak strains of about 2500 microstrain. At 16 weeks of age, mice were sacrificed, and tibiae and gonadal fat pads were dissected. Fat pads were weighed as an obesity indicator, and tibiae were imaged with microCT to measure bone structure. The left tibiae (nonloaded) were subsequently decalcified, stained with osmium, and scanned to quantify marrow fat. Results showed that HFD mice had larger tibial cross-sectional areas compared to ND mice, as well as greater marrow adiposity. However, there was no significant difference in the amount of bone adaptation in the cortical or trabecular bone between the two groups. This indicates that the bones of HFD and ND mice adapt equally well to loading.

Associations of childhood overweight and obesity with upper-extremity fracture characteristics

Childhood obesity is a growing epidemic in the United States, and is associated with an increased risk of lower-extremity physeal fractures, and fractures requiring operative intervention. However, no study has assessed the risk upper extremity physeal fractures among overweight children. Our purpose was to compare the following upper-extremity fracture characteristics in overweight and obese children with those of normal-weight/underweight children (herein, "normal weight"): mechanism of injury, anatomical location, fracture pattern, physeal involvement, and treatment types. We hypothesized that overweight and obese children would be higher risk for physeal and complete fractures with low-energy mechanisms and would therefore more frequently require operative intervention compared with normal-weight children.We performed a cross-sectional review of our database of 608 patients aged 2 to 16 years, and included patients who sustained isolated upper-extremity fractures at our level-1 pediatric tertiary care center from January 2014 to August 2017. Excluded were patients who sustained pathologic fractures and those without basic demographic or radiologic information. Using body mass index percentile for age and sex, we categorized patients as obese (≥95th percentile), overweight (85th to <95th percentile), normal weight (5th to <85th percentile), or underweight (<5th percentile). The obese and overweight groups were analyzed both separately and as a combined overweight/obese group. Demographic data included age, sex, height, and weight. Fractures were classified based on fracture location, fracture pattern (transverse, comminuted, buckle, greenstick, avulsion, or oblique), physeal involvement, and treatment type. Of the 608 patients, 58% were normal weight, 23% were overweight, and 19% were obese. There were no differences in the mean ages or sex distributions among the 3 groups.Among patients with low-energy mechanisms of injury, overweight/obese patients had significantly greater proportions of complete fractures compared with normal-weight children (complete: 65% vs 55%, P = .001; transverse: 43% vs 27%, P = .006). In addition, the overweight/obese group sustained significantly more upper-extremity physeal fractures (37%) than did the normal-weight group (23%) (P = .007).Compared with those in normal-weight children, upper-extremity fracture patterns differ in overweight and obese children, who have higher risk of physeal injuries and complete fractures caused by low-energy mechanisms.Level of Evidence: Level III, retrospective comparative study.

Preschool Obesity Is Associated With an Increased Risk of Childhood Fracture: A Longitudinal Cohort Study of 466,997 Children and Up to 11 Years of Follow-up in Catalonia, Spain

This study aimed to determine if having an overweight or obese range body mass index (BMI) at time of beginning school is associated with increased fracture incidence in childhood. A dynamic cohort was created from children presenting for routine preschool primary care screening, collected in the Information System for Research in Primary Care (SIDIAP) platform in Catalonia, Spain. Data were collected from 296 primary care centers representing 74% of the regional pediatric population. A total of 466,997 children (48.6% female) with a validated weight and height measurement within routine health care screening at age 4 years (±6 months) between 2006 and 2013 were included, and followed up to the age of 15, migration out of region, death, or until December 31, 2016. BMI was calculated at age 4 years and classified using WHO growth tables, and fractures were identified using previously validated ICD10 codes in electronic primary care records, divided by anatomical location. Actuarial lifetables were used to calculate cumulative incidence. Cox regression was used to investigate the association of BMI category and fracture risk with adjustment for socioeconomic status, age, sex, and nationality. Median follow-up was 4.90 years (interquartile range [IQR] 2.50 to 7.61). Cumulative incidence of any fracture during childhood was 9.20% (95% confidence interval [CI] 3.79% to 14.61%) for underweight, 10.06% (9.82% to 10.29%) for normal weight, 11.28% (10.22% to 12.35%) for overweight children, and 13.05% (10.69% to 15.41%) for children with obesity. Compared with children of normal range weight, having an overweight and obese range BMI was associated with an excess risk of lower limb fracture (adjusted hazard ratio [HR] = 1.42 [1.26 to 1.59]; 1.74 [1.46 to 2.06], respectively) and upper limb fracture (adjusted HR = 1.10 [1.03 to 1.17]; 1.19 [1.07 to 1.31]). Overall, preschool children with an overweight or obese range BMI had increased incidence of upper and lower limb fractures in childhood compared with contemporaries of normal weight. © 2020 The Authors. Journal of Bone and Mineral Research published by American Society for Bone and Mineral Research.

Fracture risk factors among children living in New Zealand

Factures are common during childhood. There are limited data available regarding relationships between bone fracture history and calcium intake, sugar sweetened beverages (SSBs) intake, vitamin D status, physical activity (PA), ethnicity, and body composition in New Zealand (NZ) children. Identifying groups of NZ children at risk of fracture and associated predictors may help to improve bone quality during childhood and decrease the risk of fractures throughout life. The aim of this study was to investigate fracture history and associated risk factors in New Zealand children. Children aged 8-12 years were recruited. Capillary blood spots collected from a finger prick were as analyzed for 25(OH)D concentrations. Bioelectrical impedance analysis (InBody720, Seoul, Korea) was used to measure body fat percentage (%BF). Information about fracture history, siblings' history of fractures, family osteoporosis history, PA, ethnicity, and intake of calcium containing foods, and SSBs was collected using questionnaires. Children (n = 647, 354 girls), mean ± SD age 9.8 ± 0.7 years were recruited from six Auckland primary schools. NZ European (n = 252) (NZE) and South Asian (n = 68) children reported the lowest (20.2 %) and highest (44.1 %) fracture incidence, respectively. NZE compared to South Asian children, had higher 25(OH)D concentrations (74.6 ± 19.8 vs. 48.4 ± 19.3 nmol/L, P < 0.001), higher total calcium intake (764.0 ± 394.4 vs. 592.7 ± 266.3 mg/d, P < 0.018), and lower %BF (19.5 ± 6.6 vs. 23.4 ± 8.4, P < 0.003). Māori children had the next highest fracture rate (32.5 %). This group had adequate 25(OH)D (64.2 ± 18.9 nmol/L), but high %BF (23.9 %) and most participated in vigorous PA. After stratifying by sex, binary logistic regression analysis revealed the main determinants of fracture history for boys were high %BF, low 25(OH)D, low calcium intake, high SSBs consumption, siblings' fracture history, family osteoporosis history, and being South Asian; and in girls, high SSBs consumption, siblings' fracture history, and family osteoporosis history. We found South Asian ethnicity was a significant risk factor for boys. Some children were at high risk of vitamin D deficiency and for whom supplementation may be necessary in winter. Good nutrition (especially good sources of calcium and reducing SSBs intakes) should be recommended to children during growth and development to reduce their risk of fractures.

Achilles Tendon Tissue Structure in Children with Overweight and Children with Obesity

Aim: To investigate differences in Achilles tendon structure between children with overweight/obesity and children with normal weight.Methods: Twenty-two children with obesity, 10 children with overweight, and 44 children with normal weight participated in the study. BMI% was calculated. The Achilles tendon was examined using ultrasound tissue characterization (UTC) imaging to capture a three-dimensional structure of four echo-type fibers and a cross-sectional area.Results: A significantly higher percentile of echo-types II, a lower percentile of echo-types III and IV, and a lower cross-sectional area were found for children with normal weight compared with children with overweight/obesity (p < .05). Following a piecewise linear regression model according to tendon structure, a BMI percentile of 75% was found to be the most accurate cutoff point of the children into the "unaffected" (BMI% <75%) and "affected" tendon structure groups (BMI% ≥ 75%), as the children with BMI%≥75% already had an Achilles tendon structure similar to that of the children with overweight/obesity.Conclusions: Tendon integrity as examined with UTC differs between children with obesity and children with normal weight. Children with a BMI percentile of ≥75 already demonstrate a different tendon structure pattern compared with children with BMI percentile of <75. This may put children with obesity at a greater risk of injury and should be addressed when applying an exercise program for children with overweight/obesity.

The role of PPARγ in childhood obesity-induced fractures

Globally, obesity is on the rise with ~ 30% of the world’s population now obese, and childhood obesity is following similar trends. Childhood obesity has been associated with numerous chronic conditions, including musculoskeletal disorders. This review highlights the effects of childhood adiposity on bone density by way of analyzing clinical studies and further describing two severe skeletal conditions, slipped capital femoral epiphysis and Blount’s disease. The latter half of this review discusses bone remodeling and cell types that mediate bone growth and strength, including key growth factors and transcription factors that help orchestrate this complex pathology. In particular, the transcriptional factor peroxisome proliferator-activated receptor gamma (PPARγ) is examined as it is a master regulator of adipocyte differentiation in mesenchymal stem cells (MSCs) that can also influence osteoblast populations. Obese individuals are known to have higher levels of PPARγ expression which contributes to their increased adipocyte numbers and decreased bone density. Modulating PPAR*gamma* signaling can have significant effects on adipogenesis, thereby directing MSCs down the osteoblastogenesis pathway and in turn increasing bone mineral density. Lastly, we explore the potential of PPARγ as a druggable target to decrease adiposity, increase bone density, and be a treatment for children with obesity-induced bone fractures.

Comparison of Resource Utilization and Length of Hospitalization Between Overweight and Healthy-Weight Pediatric Trauma Patients Presenting to a Pediatric Emergency Department With Moderate to Severe Injury: A Prospective Study

OBJECTIVES

Our study aimed to compare overweight and healthy-weight pediatric trauma patient outcomes, specifically with respect to hospital length of stay and resource utilization. We hypothesized that overweight pediatric trauma patients would have increased hospital length of stay and radiographic study use compared with their healthy-weight counterparts.

METHODS

This was a prospective, observational, cohort study of pediatric trauma patients aged 2 to 19 years presenting to an urban pediatric emergency department over a period of 1 year. Using measured height and weight values, body mass index (BMI) for age was calculated and plotted on the Centers for Disease Control and Prevention BMI-for-age growth charts. Patients were followed up throughout their hospitalization, and the following items were recorded: trauma alert level, mechanism of injury, age, sex, race, Glasgow Coma Scale score, total number of days in hospital, total number of intensive care unit days, total number of radiographs obtained, total number of computed tomography scans obtained, and mechanism of injury.

RESULTS

Our study population included 109 subjects. The mean age of the subjects was 9.7 years. The number of patients meeting the definition of obese (BMI for age ≥95%) was 15, or 14% of the total study population. There was no significant difference between the overweight cohort and the healthy-weight cohort found among any of the variables recorded and analyzed.

CONCLUSIONS

Although there are many chronic conditions in children associated with obesity, in the case of trauma, it does not seem to be a strong concern. A continued focus on preventing and reversing childhood obesity for other physical and mental health outcomes may be more important.

Impact of obesity on operative treatment and inpatient outcomes of paediatric limb fractures

AIMS

The aim of this study was to utilize a national paediatric inpatient database to determine whether obesity influences the operative management and inpatient outcomes of paediatric limb fractures.

PATIENTS AND METHODS

The Kids' Inpatient Database (KID) was used to evaluate children between birth and 17 years of age, from 1997 and 2012, who had undergone open and closed treatment of humeral, radial and ulna, femoral, tibial, and ankle fractures. Demographics, hospital charges, lengths of stay (LOS), and complications were analyzed.

RESULTS

Obesity was significantly associated with increased rates of open reduction and internal fixation (ORIF) for: distal humeral (odds ratio (OR) = 2.139, 95% confidence interval (CI) 1.92 to 3.44; p < 0.001); distal radius and ulna fractures (OR = 1.436, 95% CI 1.14 to 2.16; p < 0.05); distal femoral (OR = 2.051, 95% CI 1.69 to 3.60; p < 0.05); tibial and fibula shaft (OR = 2.101, 95% CI 2.10 to 3.50; p < 0.001); and ankle (OR = 1.733, 95% CI 1.70 to 2.39; p < 0.001). Older age was significantly associated with ORIF for all fractures (p < 0.05). LOS, hospital charges, and complications were significantly increased in obese patients following ORIF for upper and lower limb fractures (p < 0.05).

CONCLUSION

Obese paediatric patients are more likely to undergo ORIF in both upper and lower limb fractures and have more inpatient complications. These findings may assist in informing obese paediatric fracture patients and their families regarding the increased risk for open operative fixation and associated outcomes. Cite this article: Bone Joint J 2019;101-B:491-496.

Dynamic Simulation of Biomechanical Behaviour of the Pelvis in the Lateral Impact Loads

The objective of this study was to develop and validate a novel 3D dynamic model of a pelvic side-impactor system. The biomechanical responses of a pelvic flexible model (having .mnf file suffix) under the lateral impact load for predicting the bone fracture mechanism are investigated as well. The 3D solid model of the side-impactor system was imported into MSC/ADAMS software for analyzing the dynamic model, and the pelvic flexible model was extracted from the CT images of a Chinese female volunteer. The flexible model of the pelvis system was developed considering a wide range of mechanical properties in the bone complex and soft tissue to achieve a realistic biomechanical response during a lateral impact. Good agreements were achieved between the dynamic simulations and the experimental results of pelvic side impacts, in terms of the biomechanical criteria. The dynamic model of impactor system could be employed to investigate the hip protector effectiveness, improving the vehicle safety, and biomechanical response of the other human organs.

Effects of obesity on the healing of bone fracture in mice

Background

Obesity affects bone health to varying degrees, depending on the skeletal site (weight-bearing or non-weight-bearing) and compartment (cortical or trabecular), and is a risk factor for orthopedic disorders, including bone fractures. However, the effect and mechanisms of obesity on healing of bone fracture is little understood.

Methods

The healing bone fractures of the tibia in genetically obese mice was evaluated relative to normal mice at weekly intervals for 28 days using X-ray scans, hematoxylin and eosin (H&E) stain, and alcian blue (AB) stain. Plasma concentrations of relevant proteins were also compared via enzyme-linked immunosorbent assay (ELISA). These included calcitonin gene-related peptide (CGRP), fibroblast growth factor (FGF), transforming growth factor beta 1 (TGF-β1), and tumor necrosis factor-α (TNF-α).

Results

Bone fracture healing was delayed in the obese mice compared with the control group of normal mice, based on X-ray, H&E stain, and AB stain analysis. This was accompanied with significantly low plasma CGRP, FGF, and TGF-β1 (ELISA). However, TNF-α was significantly higher in obese mice compared with the control.

Conclusion

Bone fracture healing was significantly slower in the obese mice, relative to that of normal mice. The lower levels of CGRP, FGF, and TGF-β, and higher level of TNF-α, observed in obese mice may contribute to this observed delay in fracture healing.

Relationship between body composition and vertical ground reaction forces in obese children when walking

BACKGROUND

Obesity is now a serious worldwide challenge, especially in children. This condition can cause a number of different health problems, including musculoskeletal disorders, some of which are due to mechanical stress caused by excess body weight. The aim of this study was to determine the association between body composition and the vertical ground reaction force produced during walking in obese children.

METHODS

Sixteen children participated in the study, six females and ten males [11.5 (1.2) years old, 69.8 (15.5) kg, 1.56 (0.09) m, and 28.36 (3.74) kg/m² of body mass index (BMI)]. Total weight, lean mass and fat mass were measured by dual-energy X-ray absorptiometry and vertical forces while walking were obtained by a force platform. The vertical force variables analysed were impact and propulsive forces, and the rate of development of both. Multiple regression models for each vertical force parameter were calculated using the body composition variables as input.

FINDINGS

The impact force regression model was found to be positively related to the weight of obese children and negatively related to lean mass. The regression model showed lean mass was positively related to the propulsive rate. Finally, regression models for impact and propulsive force showed a direct relationship with body weight.

INTERPRETATION

Impact force is positively related to the weight of obese children, but lean mass helps to reduce the impact force in this population. Exercise could help obese persons to reduce their total body weight and increase their lean mass, thus reducing impact forces during sports and other activities.

Differences in intermittent postural control between normal-weight and obese children

AIM

The main objective of this study was to determine differences in postural control between obese and non-obese children.

METHODS

The study design was cross-sectional, prospective, between-subjects. Postural control variables were obtained from a group of obese children and a normal-weight control group under two different postural conditions: bipedal standing position with eyes open and bipedal standing with eyes closed. Variables were obtained for each balance condition using time domain and sway-density plot analysis of the center of pressure signals acquired by means of a force plate.

RESULTS

Pairwise comparisons revealed significant differences between obese and normal-weight children in mean velocity in antero-posterior and medio-lateral directions, ellipse area and mean distance with both eyes open and eyes closed. Normal-weight subjects obtained lower values in all these variables than obese subjects. Furthermore, there were differences between both groups in mean peaks with eyes open and in mean time with eyes closed.

CONCLUSION

Alterations were detected in the intermittent postural control in obese children. According to the results obtained, active anticipatory control produces higher center of pressure displacement responses in obese children and the periods during which balance is maintained by passive control and reflex mechanisms are of shorter duration.

Influence of body weight on bone mass, architecture and turnover

Weight-dependent loading of the skeleton plays an important role in establishing and maintaining bone mass and strength. This review focuses on mechanical signaling induced by body weight as an essential mechanism for maintaining bone health. In addition, the skeletal effects of deviation from normal weight are discussed. The magnitude of mechanical strain experienced by bone during normal activities is remarkably similar among vertebrates, regardless of size, supporting the existence of a conserved regulatory mechanism, or mechanostat, that senses mechanical strain. The mechanostat functions as an adaptive mechanism to optimize bone mass and architecture based on prevailing mechanical strain. Changes in weight, due to altered mass, weightlessness (spaceflight), and hypergravity (modeled by centrifugation), induce an adaptive skeletal response. However, the precise mechanisms governing the skeletal response are incompletely understood. Furthermore, establishing whether the adaptive response maintains the mechanical competence of the skeleton has proven difficult, necessitating the development of surrogate measures of bone quality. The mechanostat is influenced by regulatory inputs to facilitate non-mechanical functions of the skeleton, such as mineral homeostasis, as well as hormones and energy/nutrient availability that support bone metabolism. Although the skeleton is very capable of adapting to changes in weight, the mechanostat has limits. At the limits, extreme deviations from normal weight and body composition are associated with impaired optimization of bone strength to prevailing body size.

Incident Vertebral Fractures and Risk Factors in the First Three Years Following Glucocorticoid Initiation Among Pediatric Patients With Rheumatic Disorders

Vertebral fractures are an important yet underrecognized manifestation of osteoporosis in children with chronic, glucocorticoid-treated illnesses. Our goal was to determine the incidence and clinical predictors of vertebral fractures in the 3 years following glucocorticoid initiation among pediatric patients with rheumatic disorders. Incident vertebral fractures were evaluated according to the Genant semiquantitative method on lateral radiographs at baseline and then annually in the 3 years following glucocorticoid initiation. Extended Cox models were used to assess the association between vertebral fractures and clinical risk predictors. A total of 134 children with rheumatic disorders were enrolled in the study (mean ± standard deviation (SD) age 9.9 ± 4.4 years; 65% girls). The unadjusted vertebral fracture incidence rate was 4.4 per 100 person-years, with a 3-year incidence proportion of 12.4%. The highest annual incidence occurred in the first year (6.0%; 95% confidence interval (CI) 2.9% to 11.7%). Almost one-half of the patients with fractures were asymptomatic. Every 0.5 mg/kg increase in average daily glucocorticoid (prednisone equivalents) dose was associated with a twofold increased fracture risk (hazard ratio (HR) 2.0; 95% CI 1.1 to 3.5). Other predictors of increased vertebral fracture risk included: (1) increases in disease severity scores between baseline and 12 months; (2) increases in body mass index Z-scores in the first 6 months of each 12-month period preceding the annual fracture assessment; and (3) decreases in lumbar spine bone mineral density Z-scores in the first 6 months of glucocorticoid therapy. As such, we observed that a clinically significant number of children with rheumatic disorders developed incident vertebral fractures in the 3 years following glucocorticoid initiation. Almost one-half of the children were asymptomatic and thereby would have been undiagnosed in the absence of radiographic monitoring. In addition, discrete clinical predictors of incident vertebral fractures were evident early in the course of glucocorticoid therapy.

Childhood obesity, bone development, and cardiometabolic risk factors

Osteoporosis and obesity are both major public health concerns. It has long been considered that these are distinct disorders rarely found in the same individual; however, emerging evidence supports an important interaction between adipose tissue and the skeleton. Whereas overweight per se may augment bone strength, animal studies suggest that the metabolic impairment that accompanies obesity is detrimental to bone. Obesity during childhood, a critical time for bone development, likely has profound and lasting effects on bone strength and fracture risk. This notion has received little attention in children and results are mixed, with studies reporting that bone strength development is enhanced or impaired by obesity. Whether obesity is a risk factor for osteoporosis or childhood bone health, in general, remains an important clinical question. Here, we will focus on clarifying the controversial relationships between childhood obesity and bone strength development, and provide insights into potential mechanisms that may regulate the effect of excess adiposity on bone.

Sex Differences in the Effects of Weight Loss Diets on Bone Mineral Density and Body Composition: POUNDS LOST Trial

CONTEXT

Weight loss is associated with reduction in bone mineral density (BMD).

OBJECTIVE

The objective was to address the role of changes in fat mass (FM) and lean mass (LM) in BMD decline in both sexes.

DESIGN

A 2-year randomized controlled trial, the Preventing Overweight Using Novel Dietary Strategies (POUNDS-LOST).

SETTING

The setting was the general community.

PATIENTS OR OTHER PARTICIPANTS

Enrolled were 424 overweight and obese participants (mean age, 52 ± 9 y; 57% females).

INTERVENTION

Intervention included weight loss diets differing in fat, protein, and carbohydrates.

MAIN OUTCOME MEASURES

Main outcome measures were change in spine, total hip (TH), and femoral neck (FN) BMD and sex differences after dietary intervention.

RESULTS

At baseline, a stronger correlation between BMD and body composition measurements was observed in women, primarily with LM (r = 0.419, 0.507, and 0.523 for spine, FN, and TH, respectively; all P < .001). In men, only LM correlated with hip BMD (r = 0.298; P < .001). Mean weight loss at 2 years was -6.9%, without differences among diets. Two-year changes in BMD were 0.005 (P = .04), -0.014 (P < .001), and -0.014 g/cm(2) (P < .001), at the spine, TH, and FN, respectively. These changes directly correlated with changes in LM in women (r = 0.200, 0.324, and 0.260 for spine, FN, and TH, respectively), whereas FM loss correlated only with changes in TH BMD (0.274; P < .001). In men, changes in LM (-0.323; P < .001) and FM (-0.213; P = .027) negatively correlated with changes in spine BMD.

CONCLUSIONS

Weight loss diets result in sex-specific effects on BMD. Although men exhibited a paradoxical increase in spine BMD, women tended to decrease in BMD at all sites.

Changing trends in the management of children's fractures

The management of children's fractures has evolved as a result of better health education, changes in lifestyle, improved implant technology and the changing expectations of society. This review focuses on the changes seen in paediatric fractures, including epidemiology, the increasing problems of obesity, the mechanisms of injury, non-accidental injuries and litigation. We also examine the changes in the management of fractures at three specific sites: the supracondylar humerus, femoral shaft and forearm. There has been an increasing trend towards surgical stabilisation of these fractures. The reasons for this are multifactorial, including societal expectations of a perfect result and reduced hospital stay. Reduced hospital stay is beneficial to the social, educational and psychological needs of the child and beneficial to society as a whole, due to reduced costs.

Childhood Obesity Is a Chronic Disease Demanding Specific Health Care--a Position Statement from the Childhood Obesity Task Force (COTF) of the European Association for the Study of Obesity (EASO)

Childhood obesity is one of the greatest health challenges of the 21st century. The EASO COTF is convinced that classifying obesity as a chronic disease in children and adolescents is a crucial step for increasing individual and societal awareness, and for improving early diagnosis and intervention. Such a classification will enhance the development of novel preventive and treatment approaches, health care policies and systems, and the education of healthcare workers. The management of obesity prior to the appearance of co-morbidities may prevent their escalation into significant medical and psychosocial problems, and reduce their economic and societal impact. Childhood is a unique window of opportunity to influence lifetime effects on health, quality of life, prevention of non-communicable chronic diseases and disabilities. The Convention on the Rights of the Child by UNICEF states that parties shall strive to ensure that no child is deprived of his or her right of access to health care services. The EASO COTF is aiming to address these issues via educational activities for health care workers, identification of research agendas, and the promotion of collaborations among clinicians, researchers, health institutions, organizations and states across Europe.

Common polymorphism in the LRP5 gene may increase the risk of bone fracture and osteoporosis

The low-density lipoprotein receptor-related protein 5 gene (LRP5) was identified to be linked to the variation in bone mineral density and types of bone diseases. The present study was aimed at examining the association of LRP5 rs3736228 C>T gene with bone fracture and osteoporosis by meta-analysis. A systematic electronic search of literature was conducted to identify all published studies in English or Chinese on the association of the LRP5 gene with bone fracture and osteoporosis risks. All analyses were calculated using the Version 12.0 STATA software. Odds ratios (ORs) and their corresponding 95% confidence interval (95% CI) were calculated. An updated meta-analysis was currently performed, including seven independent case-control studies. Results identified that carriers of rs3736228 C>T variant in the LRP5 gene were associated with an increased risk of developing osteoporosis and fractures under 4 genetic models but not under the dominant model (OR = 1.19, 95% CI = 0.97~1.46, and P = 0.103). Ethnicity-subgroup analysis implied that LRP5 rs3736228 C>T mutation was more likely to develop osteoporosis and fractures among Asians and Caucasians in majority of subgroups. These results suggest that there is a modest effect of the LRP5 rs3736228 C>T on the increased susceptibility of bone fracture and osteoporosis.

The epidemiology of fractures in otherwise healthy children

Fractures in otherwise healthy children are important because they are common, impact on daily activity, and may identify those who may have an increased fracture risk as adults. This review covers the descriptive epidemiology of fractures in healthy children (aged 0-16) and provides an overview of what is known about the child-related determinants of fractures, dividing associations into those that are potentially modifiable and those that are not. Maternal-related influences during pregnancy have not been covered, nor have determinants related to the injury such as trauma level, landing surface, injury type, the physical environment, or societal impacts. Age, gender, low bone mass, and exposure to injury are the child-related determinants of fractures with the highest quality research showing a convincing association.

Energy absorption during impact on the proximal femur is affected by body mass index and flooring surface

Impact mechanics theory suggests that peak loads should decrease with increase in system energy absorption. In light of the reduced hip fracture risk for persons with high body mass index (BMI) and for falls on soft surfaces, the purpose of this study was to characterize the effects of participant BMI, gender, and flooring surface on system energy absorption during lateral falls on the hip with human volunteers. Twenty university-aged participants completed the study with five men and five women in both low BMI (<22.5 kg/m(2)) and high BMI (>27.5 kg/m(2)) groups. Participants underwent lateral pelvis release experiments from a height of 5 cm onto two common floors and four safety floors mounted on a force plate. A motion-capture system measured pelvic deflection. The energy absorbed during the initial compressive phase of impact was calculated as the area under the force-deflection curve. System energy absorption was (on average) 3-fold greater for high compared to low BMI participants, but no effects of gender were observed. Even after normalizing for body mass, high BMI participants absorbed 1.8-fold more energy per unit mass. Additionally, three of four safety floors demonstrated significantly increased energy absorption compared to a baseline resilient-rolled-sheeting system (% increases ranging from 20.7 to 28.3). Peak system deflection was larger for high BMI persons and for impacts on several safety floors. This study indicates that energy absorption may be a common mechanism underlying the reduced risk of hip fracture for persons with high BMI and for those who fall on soft surfaces.