The association between bone mineral density, metacarpal morphometry, and upper limb fractures in children: a population-based case-control study

Evaluation of the First Metacarpal Bone Head and Distal Radius Bone Architecture Using Fractal Analysis of Adolescent Hand-Wrist Radiographs

The purpose of this study was to investigate changes in bone trabecular structure during adolescence using the fractal analysis (FA) method on hand-wrist radiographs (HWRs) and to evaluate the relationship of these changes with pubertal growth stages. HWRs of healthy individuals aged 8-18 years were included (N = 600). Pubertal stages were determined by the Fishman method and divided into 10 groups (early puberty [EP], pre-peak [PRPK], peak [PK], post-peak [PTPK], late puberty [LP]). FA was performed using FIJI (ImageJ) software and the BoneJ plugin on circular regions of interest (ROIs) selected from the first metacarpal bone head and distal radius. Image processing steps were applied according to the White and Rudolph method. Differences between groups were statistically evaluated. Fractal dimension (FD) values of the distal radius (RAFAM) and metacarpal bone head (MAFAM) showed significant differences according to pubertal growth stages (p < 0.05). The highest FD value was observed in the LP group, and the lowest FD value was observed in the EP group (except MAFAM in females). FD generally increased from EP to LP in the whole population, but a significant decrease was observed in all groups during the PK period. This decrease was more pronounced in RAFAM of males. These findings suggest a potential decrease of bone mechanical properties in the PK, which is found the be more suitable for orthodontic treatment in the literature. FA on HWRs is a useful and sensitive tool for quantitatively assessing pubertal changes in trabecular bone microarchitecture. The findings demonstrate a significant decrease in FD in both bone regions during the pubertal growth spurt, particularly at the peak period. This may indicate a temporary reduction in bone mechanical strength during this critical stage and could contribute to increased distal radius fracture incidence. Clinically, the relationship between FD and pubertal stages suggests this method could serve as a valuable biomarker in orthodontic treatment planning, allowing for optimized timing of interventions. Furthermore, it may aid in pediatric fracture risk assessment, potentially leading to preventative strategies for high-risk individuals.

Utility of BoneXpert in assessing bone age and bone health in Indian children and youth with type 1 diabetes mellitus

INTRODUCTION

BoneXpert (BX) performs digital radiogrammetry and reports metacarpal index (MCI) besides bone age (BA) evaluation. Its utility in subjects with type-1 diabetes (T1D) has not been reported. We conducted this study with following objectives: 1) To study the utility of BX in the assessment of BA in Indian children and youth (CY) with T1D and 2) To assess association of MCI (measured by BX) and bone health in Indian CY with T1D.

METHODS

The MCI and BA were assessed retrospectively in 1272 subjects with T1D using digitalised left-hand x-rays. The demographic, anthropometric, clinical, dietary, biochemistry, dual x-ray absorptiometry (DXA) data and peripheral quantitative computed tomography (pQCT) data collection were performed using standard protocols and were extracted from hospital records.

RESULTS

The root mean square error of BX with respect to reference and true bone age by TW-3 method were estimated to be 0.72 years and 0.67 years respectively in Indian CY with T1D. The BX provided MCI results were in concordance with the DXA derived bone mineral density (r = 0.551) and pQCT derived cortical density (r = 0.318) measurements; MCI correlated with trabecular density at the tibia (r = 0.212). 51.5 % subjects with T1D had significantly decreased MCI. Height, tanner stage, vitamin D concentrations showed positive correlation while HbA1c and disease duration had negative correlation with MCI.

CONCLUSION

BX may be used for accurate assessment of BA by TW-3 method and for screening for bone health in Indian CY with T1D.

IGF1 Genetic Polymorphism and the Association between Vitamin D Status and BMI Percentiles in Children

Both the IGF1 axis and hypovitaminosis D play a role in childhood obesity, either as a cause or a causality. While some studies suggest an interrelation between vitamin D status, IGF1, and obesity, this mechanism remains obscure. The aim of this study, therefore, was to explore associations between four genetic polymorphisms in the IGF1 axis in hypovitaminosis D-related obesity. The study included 116 pre-pubertal Israeli Arab children (52 girls), mean age 9.4 ± 2.6. Serum 25(OH)D was measured and anthropometric measures were obtained. Genomic DNA was extracted from peripheral EDTA-treated anti-coagulated blood using a standard protocol. Genotypes were determined using the Taqman allelic discrimination assay. The IGF genetic score was computed according to the additive genetic score model. A moderate-to-high negative correlation (r = 0.580, p < 0.05) was seen between the vitamin D status and body mass index (BMI) percentile of participants with high GS. Yet, no correlations were seen between vitamin D status and BMI percentile for participants with a low-to-moderate genetic score (GS) (GS ≤ 2). These results suggest that IGF1 genetic scores associated with elevated circulating IGF1 may indicate a tendency toward developing hypovitaminosis D-associated obesity.

Vitamin D supplementation for improving bone density in vitamin D-deficient children and adolescents: systematic review and individual participant data meta-analysis of randomized controlled trials

BACKGROUND

Vitamin D supplements are widely used for improving bone health in children and adolescents, but their effects in vitamin D-deficient children are unclear.

OBJECTIVES

This study aimed to examine whether the effect of vitamin D supplementation on bone mineral density (BMD) in children and adolescents differs by baseline vitamin D status and estimate the effect in vitamin D-deficient individuals.

METHODS

This is a systematic review and individual participant data (IPD) meta-analysis. We searched the Cochrane Central Register of Controlled Trials, MEDLINE, MBASE, CINAHL, AMED, and ISI Web of Science (until May 27, 2020) for randomized controlled trials (RCTs) of vitamin D supplementation reporting bone density outcomes after ≥6 mo in healthy individuals aged 1-19 y. We used two-stage IPD meta-analysis to determine treatment effects on total body bone mineral content and BMD at the hip, femoral neck, lumbar spine, and proximal and distal forearm after 1 y; examine whether effects varied by baseline serum 25-hydroxyvitamin D [25(OH)D] concentration, and estimate treatment effects for each 25(OH)D subgroup.

RESULTS

Eleven RCTs were included. Nine comprising 1439 participants provided IPD (86% females, mean baseline 25(OH)D = 36.3 nmol/L). Vitamin D supplementation had a small overall effect on total hip areal BMD (weighted mean difference = 6.8; 95% confidence interval: 0.7, 12.9 mg/cm2; I2 = 7.2%), but no effects on other outcomes. There was no clear evidence of linear or nonlinear interactions between baseline 25(OH)D and treatment; effects were similar in baseline 25(OH)D subgroups (cutoff of 35 or 50 nmol/L). The evidence was of high certainty.

CONCLUSIONS

Clinically important benefits for bone density from 1-y vitamin D supplementation in healthy children and adolescents, regardless of baseline vitamin D status, are unlikely. However, our findings are mostly generalizable to White postpubertal girls and do not apply to those with baseline 25(OH)D outside the studied range or with symptomatic vitamin D deficiency (e.g., rickets). This study was preregistered at PROSPERO as CRD42017068772. https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42017068772.

An intelligent composite model incorporating global / regional X-rays and clinical parameters to predict progressive adolescent idiopathic scoliosis curvatures and facilitate population screening

BACKGROUND

Adolescent idiopathic scoliosis (AIS) affects up to 5% of the population. The efficacy of school-aged screening remains controversial since it is uncertain which curvatures will progress following diagnosis and require treatment. Patient demographics, vertebral morphology, skeletal maturity, and bone quality represent individual risk factors for progression but have yet to be integrated towards accurate prognostication. The objective of this work was to develop composite machine learning-based prediction model to accurately predict AIS curves at-risk of progression.

METHODS

1870 AIS patients with remaining growth potential were identified. Curve progression was defined by a Cobb angle increase in the major curve of ≥6° between first visit and skeletal maturity in curves that exceeded 25°. Separate prediction modules were developed for i) clinical data, ii) global/regional spine X-rays, and iii) hand X-rays. The hand X-ray module performed automated image classification and segmentation tasks towards estimation of skeletal maturity and bone mineral density. A late fusion strategy integrated these domains towards the prediction of progressive curves at first clinic visit.

FINDINGS

Composite model performance was assessed on a validation cohort and achieved an accuracy of 83.2% (79.3-83.6%, 95% confidence interval), sensitivity of 80.9% (78.2-81.9%), specificity of 83.6% (78.8-84.1%) and an AUC of 0.84 (0.81-0.85), outperforming single modality prediction models (AUC 0.65-0.78).

INTERPRETATION

The composite prediction model achieved a high degree of accuracy. Upon incorporation into school-aged screening programs, patients at-risk of progression may be prioritized to receive urgent specialist attention, more frequent follow-up, and pre-emptive treatment.

FUNDING

Funding from The Society for the Relief of Disabled Children was awarded to GKHS.

Decreased bone mass in adolescents with bone fragility fracture but not in young children: a case-control study

Background

The incidence of distal forearm fracture due to minimal/moderate trauma shows a bimodal distribution for age at event, with one peak occurring during early adolescence, in both boys and girls and the other one in postmenopausal females. The aim of this study was, therefore, to document whether the relationship between bone mineral density and fracture is different in young children compared with adolescents.

Methods

A matched-pair, case-control study has been conducted to evaluate bone mineral density in 469 young children and 387 adolescents of both sexes, with/without fracture due to minimal/moderate trauma with assurance that the compared groups were equally susceptible to the outcome event. All fractures were radiographically confirmed. The study utilized bone mineral areal density of the total body, spine, hips, and forearm; volumetric bone mineral density of the forearm; and metacarpal radiogrammetry measurements. The study controlled for skeletal development, bone geometry, body composition, hand grip strength, calcium intake, and vitamin D status.

Results

Adolescents with distal forearm fracture have reduced bone mineral density at multiple skeletal regions of interest. This was documented by the bone mineral areal density measurements at multiple skeletal sites (p < 0.001), volumetric bone mineral density measurements of the forearm (p < 0.0001), and metacarpal radiogrammetry (p < 0.001). Adolescent females with fracture had reduced cross-sectional areas of the radius and metacarpals. The bone status of young female and male children with fracture was no different to its controls. Increased body fatness was more prevalent among fracture cases than in controls. Around 72% of young female and male children with fracture had serum 25-hydroxyvitamin D levels below the threshold of 31 ng/ml, compared with only 42% of female controls and to 51% of male controls.

Conclusions

Adolescents with bone fragility fracture had reduced bone mineral density at multiple skeletal regions of interest, whereas this was not the case with younger children. The results of the study may have implications for the prevention of bone fragility in this segment of the pediatric population.

Girl predominance in trampoline-related forearm shaft fractures and their increasing incidence since 2000

BACKGROUND

There are reports of increasing incidence of forearm shaft fractures in children. Their treatment has been preferably nonoperative but surgical fixation has gained popularity due to elastic stable intramedullary nailing. We aimed to study whether the incidence of pediatric both-bone forearm shaft fractures and their operative care have changed since year 2000. Trampoline injuries, in particular, and their treatment, re-displacement and short-term outcomes were the secondary outcomes of the study.

METHODS

A population-based study in the geographic catchment area of Oulu University Hospital district in 20-years of time period (2000 - 2019) was performed. Altogether 481 diaphyseal both-bone forearm fractures in children (< 16 years) were included. Age- and sex-related incidence rates were determined, by using the official numbers of the population-in-risk by Statistics Finland. Trampoline jumping and other types of injury were reviewed, as well as particulars of treatment and outcomes.

RESULTS

The incidence of diaphyseal both-bone forearm fractures increased from 9.4/100 000 in 2000-2001 to 41.7/100 000 in 2018-2019 (P < 0.001). Surgical treatment increased respectively (from 8.8/100 000 in 2000-2001 to 35.3/100 000 in 2018-2019, P < 0.0001). Trampoline injuries explained one in three (29%) of all fractures; they increased from 0% in 2000-2001 to 36.6% in 2018-2019 (P < 0.001). During the last four years of the study (2016-2019), most trampoline-related injuries occurred among girls (61.2%), compared to boys (38.8%) (P = 0.031). Trampoline-related injuries comprised 46.9% of all fractures in girls, compared to 26.0% among boys (Diff. 20.8%, 4.7% to 36.1%, P = 0.009). The mean age of the patients elevated from 6.4 years (2000-2001) to 8.6 years (2018-2019) (P = 0.015). Boys predominated (69.6%) in 2000-2009 but during the last ten years, there was no statistical difference in distribution between the genders (males 54.6%, P = 0.11).

CONCLUSIONS

During the twenty-year's of study period, the incidence of pediatric diaphyseal forearm fractures increased fivefold. Trampolining was the most usual single reason for the fractures. More attention should be focused to increase the safety of trampoline jumping, in particular among the girls.

Effect of soluble corn fibre and calcium supplementation on bone mineral content and bone mineral density in preadolescent Malaysian children-a double-blind randomised controlled trial (PREBONE-Kids Study)

Soluble corn fibre (SCF) with calcium did not improve bone indices after 1 year in preadolescent children.

INTRODUCTION

SCF has been reported to improve calcium absorption. We investigated the long-term effect of SCF and calcium on bone indices of healthy preadolescent children aged 9-11 years old.

METHODS

In a double-blind, randomised, parallel arm study, 243 participants were randomised into four groups: placebo, 12-g SCF, 600-mg calcium lactate gluconate (Ca) and 12-g SCF + 600-mg calcium lactate gluconate (SCF + Ca). Total body bone mineral content (TBBMC) and total body bone mineral density (TBBMD) were measured using dual-energy X-ray absorptiometry at baseline, 6 and 12 months.

RESULTS

At 6 months, SCF + Ca had a significant increase in TBBMC from baseline (27.14 ± 6.10 g, p = 0.001). At 12 months, there was a significant increase in TBBMC from baseline in the SCF + Ca (40.28 ± 9.03 g, p = 0.001) and SCF groups (27.34 ± 7.93 g, p = 0.037). At 6 months, the change in TBBMD in the SCF + Ca (0.019 ± 0.003 g/cm²) and Ca (0.014 ± 0.003 g/cm²) groups was significantly different (p < 0.05) from SCF (0.004 ± 0.002 g/cm²) and placebo (0.002 ± 0.003 g/cm²). However, the changes in TBBMD and TBBMC were not significantly different among groups at 12 months.

CONCLUSION

SCF did not increase TBBMC and TBBMD in Malaysian children after 1 year although calcium supplementation increased TBBMD at 6 months. Further work is needed to fully understand the mechanism and health benefits of prebiotics in this study population.

CLINICAL TRIAL REGISTRATION

https://clinicaltrials.gov/ct2/show/NCT03864172.

Effects of vitamin D on bone density in healthy children: A systematic review

Skeletal growth and bone health are very important in children. The effective role of vitamin D in bone mineral density has been observed in children and adolescents. This systematic review study evaluated the effects of vitamin D on bone density in healthy children with the help of valid databases and the website of clinical trials. The results of experimental, clinical, retrospective, prospective, double-blind, and randomized studies were used. Articles that appropriately covered the topic and had the proper content structure were selected for this review. Out of a total of 132 articles, finally, 13 articles were selected based on inclusion and exclusion criteria for further study, the results of which show the association between serum levels of vitamin D and bone mineral density and health. However, in some articles, the relationship between other influential variables such as age and nutrition on bone density in children was identified. In general, the current systematic review demonstrates the role of vitamin D on bone density in healthy children, so that in children studied, vitamin D is at different levels and complications related to bone density are observed in many children. It is recommended that more clinical and longitudinal studies be performed to further understand the role of vitamin D levels in bone health in children.

Vitamin D level, body mass index and fracture risk in children: vitamin D deficiency and fracture risk

The objective of this study was to determine the impacts of preventable causes of fracture, such as vitamin D deficiency, disturbed calcium homeostasis and obesity on fracture occurrence in minor traumas. In this way, the effects of relevant parameters on fracture may be further elucidated. A prospective case-control study in children aged 2-18 years children with and without fractures was performed. Participants with a pediatric trauma score higher than 10 presenting to minor trauma were included to exclude the significant impact of severe trauma on fracture. The effects of obesity, parameters associated with vitamin D and Ca homeostasis on fracture occurrence were evaluated. Univariate and multivariate analyses were used to test for associations between fracture status and the assessed variables. The relationships between the variables and the odds of fracture occurrence were examined using logistic regression models. The sample consisted of 76 patients and 50 controls. There were no significant differences between the patients and controls in terms of age, sex, trauma type and pubertal period. The patients had a significantly higher mean BMI percentile (61.2 ± 30.7, 36.7 ± 30.7; P < 0.001). Likewise, patients were more likely than controls to have a lower mean 25(OH)D level and mean phosphorus level (respectively, 13.4 ± 7.0, 17.3 ± 7.8; P = 0.004, and 4.6 ± 0.7, 5.1 ± 0.8; P < 0.001). Moreover, fractures were substantially more frequent in children with vitamin D deficiency (<20 ng/mL, χ2: 7.781, df: 1, P = 0.005). In the multivariate logistic model, BMI percentile and vitamin D levels remained significantly associated with increased odds of fracture [1.02 (1.01-1.04), P < 0.001 and 0.93 (0.89-0.98), P = 0.01]. The present study supports an association of high BMI and vitamin D deficiency with an increased odds of fracture occurrence in children. The findings may help physicians to reduce the risk factors of fracture by preventive efforts. Thus, unexpected health costs and morbidity may be minimized.

Roux-en-Y gastric bypass alters intestinal glucose transport in the obese Zucker rat

INTRODUCTION

The gastrointestinal tract plays a major role in regulating glucose homeostasis and gut endocrine function. The current study examines the effects of Roux-en-Y gastric bypass (RYGB) on intestinal GLP-1, glucose transporter expression and function in the obese Zucker rat (ZR).

METHODS

Two groups of ZRs were studied: RYGB and sham surgery pair-fed (PF) fed rats. Body weight and food intake were measured daily. On post-operative day (POD) 21, an oral glucose test (OGT) was performed, basal and 30-minute plasma, portal venous glucose and glucagon-like peptide-1 (GLP-1) levels were measured. In separate ZRs, the biliopancreatic, Roux limb (Roux) and common channel (CC) intestinal segments were harvested on POD 21.

RESULTS

Body weight was decreased in the RYGB group. Basal and 30-minute OGT plasma and portal glucose levels were decreased after RYGB. Basal plasma GLP-1 levels were similar, while a 4.5-fold increase in GLP-1 level was observed in 30-minute after RYGB (vs. PF). The increase in basal and 30-minute portal venous GLP-1 levels after RYGB were accompanied by increased mRNA expressions of proglucagon and PC 1/3, GPR119 protein in the Roux and CC segments. mRNA and protein levels of FFAR2/3 were increased in Roux segment. RYGB decreased brush border glucose transport, transporter proteins (SGLT1 and GLUT2) and mRNA levels of Tas1R1/Tas1R3 and α-gustducin in the Roux and CC segments.

CONCLUSIONS

Reductions in intestinal glucose transport and enhanced post-prandial GLP-1 release were associated with increases in GRP119 and FFAR2/3 after RYGB in the ZR model. Post-RYGB reductions in the regulation of intestinal glucose transport and L cell receptors regulating GLP-1 secretion represent potential mechanisms for improved glycemic control.

Assessment of bone mineral density in children with congenital cyanotic heart disease

BACKGROUND

Cyanotic CHD is one of many disorders in paediatrics that influence the health of children in different clinical aspects. One of the fundamental aspects that may be affected is bone mineral density.

OBJECTIVES

The aim of our study is to assess bone mineral density in children with congenital cyanotic heart disease of different anatomical diagnoses.

DESIGN/METHODS

Cross-sectional, observational study included 39 patients (20 males) with congenital cyanotic heart disease of different anatomical diagnoses following with the cardiology clinic in Mansoura University children's hospital. All patients were subjected to anthropometric measures, oxygen saturation assessment, and lumber bone mineral density using dual-energy X-ray absorptiometry.

RESULTS

Six patients (15.4%) out of the 39 included patients showed bone mineral density reduction, 13 patients (33.3%) showed bone mineral density with Z-score between -1 and -2, while 20 patients (51.3%) showed bone mineral density with Z-score more than -1.

CONCLUSION

Low bone mineral density can be found in children with cyanotic CHD, making it important to consider bone mineral density assessment and early treatment if needed to avoid further complications.

Obesity as a Predictor of Outcomes in Type III and Type IV Supracondylar Humerus Fractures

OBJECTIVES

To investigate the association of obesity with fracture characteristics and outcomes of operatively treated pediatric supracondylar humerus fractures.

DESIGN

Retrospective multicenter.

SETTING

Two Level I pediatric hospitals.

PATIENTS

Patients (age <18 years) with operatively treated Gartland type III and type IV fractures 2010-2014.

INTERVENTION

Closed or open reduction and percutaneous pinning of supracondylar humerus fractures.

MAIN OUTCOME MEASURE

Incidence of Gartland IV fracture, preoperative nerve palsy, open reduction and complication rates.

RESULTS

Patients in the obese group had a significantly higher likelihood of having a Gartland IV fracture (not obese: 17%; obese: 35%; P = 0.007). There was a significantly higher incidence of nerve palsy on presentation in the obese group (not obese: 20%; obese: 33%; P = 0.03). No significant differences were found between groups regarding incidence of open reduction, compartment syndrome, and rates of reoperation.

CONCLUSIONS

The present study demonstrates that obese children with a completely displaced supracondylar humerus fractures have an increased risk of Gartland type IV and preoperative nerve palsy compared with normal weight children.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

The "Goldilocks Day" for Children's Skeletal Health: Compositional Data Analysis of 24-Hour Activity Behaviors

Optimization of children's activity behaviors for skeletal health is a key public health priority, yet it is unknown how many hours of moderate to vigorous physical activity (MVPA), light physical activity (LPA), sedentary behavior, or sleep constitute the best day-the "Goldilocks Day"-for children's bone structure and function. To describe the best day for children's skeletal health, we used data from the cross-sectional Child Health CheckPoint. Included participants (n = 804, aged 10.7 to 12.9 years, 50% male) underwent tibial peripheral quantitative CT to assesses cross-sectional area, trabecular and cortical density, periosteal and endosteal circumference, polar moment of inertia, and polar stress-strain index. Average daily time-use composition (MVPA, LPA, sedentary time, and sleep) was assessed through 8-day, 24-hour accelerometry. Skeletal outcomes were regressed against time-use compositions expressed as isometric log-ratios (with quadratic terms where indicated), adjusted for sex, age, pubertal status, and socioeconomic position. The models were used to estimate optimal time-use compositions (associated with best 5% of each skeletal outcome), which were plotted in three-dimensional quaternary figures. The center of the overlapping area was considered the Goldilocks Day for skeletal health. Children's time-use composition was associated with all skeletal measures (all p ≤ 0.001) except cross-sectional area (p = 0.72). Days with more sleep and MVPA, less sedentary time, and moderate LPA were beneficially associated with skeletal measures, except cortical density, which was adversely associated. The Goldilocks daily time-use composition for overall skeletal health was center (range): 10.9 (10.5 to 11.5) hours sleep; 8.2 (7.8 to 8.8) hours sedentary time; 3.4 (2.8 to 4.2) hours LPA, and 1.5 (1.3 to 1.5) hours MVPA. Estimated optimal sleep duration is consistent with current international guidelines (9 to 11 hours), while estimated optimal MVPA exceeds recommendations of at least 60 min/d. This first study to describe optimal durations of daily activities for children's skeletal health provides evidence to underpin guidelines. © 2020 American Society for Bone and Mineral Research (ASBMR).

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.

The Association of Vitamin D in Youth and Early Adulthood with Bone Mineral Density and Microarchitecture in Early Adulthood

This study aimed to describe the association of vitamin D status at different stages of growth with bone measures in adolescence and early adulthood. There were 415 participants followed from age 8 to 16, and 201 further followed to age 25. Areal bone mineral density (BMD) at the spine, hip and total body was measured by dual-energy X-ray absorptiometry at ages 16 and 25, and tibial and radial trabecular and cortical bone microarchitecture by high resolution peripheral quantitative computerised tomography at age 25. Serum 25-hydroxyvitamin D (25OHD) concentrations were measured at ages 8, 16 and 25. Multivariable linear regression was used to analyse the association of 25OHD concentrations at three timepoints with bone measures at ages 16 and 25. The proportion of participants with vitamin D deficiency (< 50 nmol/L) was 11%, 43% and 41% at three timepoints, respectively. Serum 25OHD concentrations at age 8 were not significantly associated with any bone measures at age 16 or 25. Serum 25OHD concentrations at age 16 had a significant association with higher BMD at nearly all sites at ages 16 and 25 as well as lower radial porosity and more compact trabecular microarchitecture (higher density, increased number and reduced separation) at both the radius and tibia at age 25. Serum 25OHD concentrations at age 25 were only associated with hip BMD. Higher vitamin D concentrations in adolescence, to a lesser extent at age 25, have beneficial associations with BMD and bone microarchitecture in early adulthood. Optimising vitamin D status particularly during adolescence should be a priority.

Femoral stress is prominently associated with fracture risk in children: The Generation R Study

Bone modeling is an important process in the growing skeleton. An inadequate bone modeling in response to mechanical loads would lead some children to develop weaker bones than others. The resulting higher stresses in the bones would render them more susceptible to fracture. We aimed to examine the association between femoral stress (FS) derived from structural parameters and BMD in relation to incident fractures in children. Bone stress was evaluated at the medial femoral neck, a skeletal site subject to large forces during normal locomotion. This study comprises 1840 children from the Generation R Study, with whole body and hip DXA scans at a mean age of 6.01 years. Hip structural analysis (HSA) was used to measure femur geometry for the FS calculation. Data on fractures occurring over the following 4 years after the DXA assessment were obtained by questionnaire. Incident fracture was observed in 7.6% of the participating children. Cox-multivariate regression analysis, described as hazard ratios (HR), showed that after adjustment for sex, ethnicity, age, weight and lean mass fraction, there was a significant increase in the risk of incident fracture for every standard deviation (SD) decrease in total body BMD (HR: 1.35, 95% CI 1.05-1.74, p-value = 0.021), femoral neck BMD (HR: 1.31, 95% CI 1.09-1.58, p-value = 0.005) and narrow neck BMD (HR: 1.39, 95% CI 1.14-1.68, p-value = 0.001). Whereas, every increment of one SD in femoral stress resulted in 1.33 increased risk of incident fractures (HR: 1.33, 95% CI 1.13-1.57, p-value = 0.001). This association remained (borderline) significant after the adjustment for DXA derived BMD measurements. Our results show that increased bone stress may underlie greater susceptibility to traumatic fractures in children (partially independent of BMD) and underscore the utility of hip DXA scans for the assessment of paediatric bone health and specifically fracture risk.

Recovery of Bone Mineral Mass After Upper Limb Fractures in Children and Teenagers

BACKGROUND

Loss of bone mineral mass and muscle atrophy are predictable consequences of cast-mediated immobilization following wrist and forearm fractures. This study aimed to prospectively determine whether previously reported lower bone mineral mass following immobilization for wrist and forearm fractures in children and teenagers had recovered at 6- and 18-month follow-up.

METHODS

We recruited 50 children and teenagers who underwent a cast-mediated immobilization for a forearm or wrist fracture. Dual-energy x-ray absorptiometry scans of different skeletal sites were performed at the time of fracture, at cast removal, at 6 and at 18-month follow-up. Injured patients were paired with healthy controls according to sex and age. Dual-energy x-ray absorptiometry values were compared between groups and the injured and uninjured forearms of the patients.

RESULTS

At the time of fracture, injured and healthy subjects showed no differences between their bone mineral density (BMD) and bone mineral content (BMC) z-scores at the lumbar spine, or between their BMDs at the peripheral wrist. At cast removal, upper limb bone mineral variables were significantly lower in the injured group (except for the ultradistal radius) than in the uninjured group, with differences ranging from 3.8% to 10.2%. No residual decrease in bone mineral variables was observed at any upper limb site at 6- and 18-month follow-up (28 injured patients). Significant residual increases in the BMDs and BMCs were observed for the injured group's ultradistal radius and whole wrists (+4.8% to +5.2%).

CONCLUSIONS

A rapid bone mass reversal occurs by resumption of mobilization, with full bone recovery 6 months after a forearm or wrist fracture. Finally, healing bone callus could introduce a bias into the interpretation of BMD and BMC data at the fracture site, not only at cast removal but also 18 months after the fracture.

Diagnosis of osteoporotic vertebral fractures in children

Osteoporosis is a generalised disorder of the skeleton with reduced bone density and abnormal bone architecture. It increases bone fragility and renders the individual susceptible to fractures. Fractures of the vertebrae are common osteoporotic fractures. Vertebral fractures may result in scoliosis or kyphosis and, because they may be clinically silent, it is imperative that vertebral fractures are diagnosed in children accurately and at an early stage, so the necessary medical care can be implemented. Traditionally, diagnosis of osteoporotic vertebral fractures has been from lateral spine radiographs; however, a small number of studies have shown that dual energy x-ray absorptiometry is comparable to radiographs for identifying vertebral fractures in children, while allowing reduced radiation exposure. The diagnosis of vertebral fractures from dual energy x-ray absorptiometry is termed vertebral fracture assessment. Existing scoring systems for vertebral fracture assessment in adults have been assessed for use in children, but there is no standardisation and observer reliability is variable. This literature review suggests the need for a semiautomated tool that (compared to the subjective and semiquantitative methods available) will allow more reliable and precise detection of vertebral fractures in children.

Metacarpal Indices and Their Association with Fracture in South African Children and Adolescents

This prospective study assessed whether metacarpal indices predict fracture risk in children and adolescents. Radiogrammetry was performed at the second metacarpal midshaft on annual hand-wrist radiographs of 359 South African (SA) children aged 10-17 years. Bone length, bone width, and medullary width were measured, and the following proxies for bone strength calculated: metacarpal index (MCI), bone mineral density (BMD), section modulus (SM), stress-strain index (SSI), and slenderness index (SLI). Height and weight were measured annually. Self-reported physical activity (PA) and fracture history were obtained at ages 15 years (for the preceding 12 months) and 17 years, respectively. At 17 years, 82 (23%) participants (black, 16%; white, 42%; p < 0.001) reported a previous fracture. None of the bone measures or indices were associated with fracture in black participants. In white females, after adjusting for PA, a 1 standard deviation (SD) greater SLI doubled the fracture risk [odds ratio (OR) 2.08; 95% confidence interval (CI) 1.08, 3.98]. In white males, a 1 SD greater BMD was associated with a 2.62-fold increase in fracture risk (OR 3.62; 95% CI 1.22, 10.75), whilst a 1 SD greater SM (OR 2.29; 95% CI 1.07, 4.89) and SSI (OR 2.23; 95% CI 1.11, 4.47) were associated with a more than twofold increase in fracture risk, after height, and PA adjustment. No single index consistently predicted fracture across the four groups possibly due to ethnic and sex differences in bone geometry, muscle mass, and skeletal loading. Metacarpal radiogrammetry did not reliably predict fracture in SA children.

Does vitamin D supplementation improve bone density in vitamin D-deficient children? Protocol for an individual patient data meta-analysis

INTRODUCTION

Our previous study-level (aggregate data) meta-analysis suggested that vitamin D supplements may be beneficial for bone density specifically in children with vitamin D deficiency. However, the misclassification of vitamin D status inherent in study-level data means that the results are not definitive and cannot provide an accurate assessment of the size of any effect. Therefore, we propose to undertake an individual patient data (IPD) meta-analysis to determine whether the effect of vitamin D supplementation on bone density in children differs according to baseline vitamin D status, and to specifically estimate the effect of vitamin D in children who are vitamin D deficient.

METHODS AND ANALYSIS

This study has been designed to adhere to the Preferred Reporting Items for Systematic Review and Meta-Analyses of IPD statement. We will include randomised placebo-controlled trials of vitamin D supplementation reporting bone density outcomes at least 6 months after the study commenced in children and adolescents (aged <20 years) without coexistent medical conditions or treatments causing osteoporosis. We will update the search of the original review to cover the period 2009-2017, using the same methods as the original review. Fully anonymised data on all randomised patients will be requested. Outcomes will be femoral neck, total hip, lumbar spine and proximal and distal forearm bone mineral density, and total body bone mineral content. A two-stage IPD meta-analysis will be used to examine the effect of baseline serum 25-hydroxyvitamin D (25(OH)D) on treatment effect for each bone density outcome. Restricted maximum likelihood will be used to estimate the random-effects meta-analysis models, with 95% CI for summary effects. Heterogeneity will be assessed by I2 and potential publication bias (small-study effects) and availability bias by funnel plots, Egger's test and Peter's test.

ETHICS AND DISSEMINATION

Ethics approval will not be required as the data are to be used for the primary purpose for which they were collected and all original individual studies had ethics approval. Results of the IPD meta-analysis will be submitted for publication in a peer-reviewed journal.

PROSPERO REGISTRATION NUMBER

CRD42017068772.

Effects of Recombinant Human Lactoferrin on Osteoblast Growth and Bone Status in Piglets

Lactoferrin (LF), an ~80 kDa iron-binding glycoprotein, modulates many biological effects, including antimicrobial and immunomodulatory activities. Recently, it was shown that LF also regulates bone cell activity, suggesting its therapeutic effect on postmenopausal bone loss. However, a minimal amount is known regarding the effects of recombinant human LF (rhLF) supplementation on bone status in young healthy infants. We found osteoblast cell differentiation was significantly promoted in vitro. Furthermore, treatment of human osteoblast cells with rhLF rapidly induced phosphorylation of p44/p42 mitogen-activated protein kinase (p44/p42 MAPK, ERK1/2). In order to investigate the effects of rhLF on bone status in vivo, we used a piglet model, which is a useful model for human infants. Piglets were supplemented with rhLF milk for 30 days. Bone formation markers, Serum calcium concentration, bone mineral density (BMD), bone mineral content (BMC), tibia bone strength, and the overall metabolite profile analysis showed that rhLF was advantageous to the bone growth in piglets. These findings suggest that rhLF supplementation benefits neonate bone health by modulating bone formation.

The National Osteoporosis Foundation's position statement on peak bone mass development and lifestyle factors: a systematic review and implementation recommendations

Lifestyle choices influence 20-40 % of adult peak bone mass. Therefore, optimization of lifestyle factors known to influence peak bone mass and strength is an important strategy aimed at reducing risk of osteoporosis or low bone mass later in life. The National Osteoporosis Foundation has issued this scientific statement to provide evidence-based guidance and a national implementation strategy for the purpose of helping individuals achieve maximal peak bone mass early in life. In this scientific statement, we (1) report the results of an evidence-based review of the literature since 2000 on factors that influence achieving the full genetic potential for skeletal mass; (2) recommend lifestyle choices that promote maximal bone health throughout the lifespan; (3) outline a research agenda to address current gaps; and (4) identify implementation strategies. We conducted a systematic review of the role of individual nutrients, food patterns, special issues, contraceptives, and physical activity on bone mass and strength development in youth. An evidence grading system was applied to describe the strength of available evidence on these individual modifiable lifestyle factors that may (or may not) influence the development of peak bone mass (Table 1). A summary of the grades for each of these factors is given below. We describe the underpinning biology of these relationships as well as other factors for which a systematic review approach was not possible. Articles published since 2000, all of which followed the report by Heaney et al. [1] published in that year, were considered for this scientific statement. This current review is a systematic update of the previous review conducted by the National Osteoporosis Foundation [1]. [Table: see text] Considering the evidence-based literature review, we recommend lifestyle choices that promote maximal bone health from childhood through young to late adolescence and outline a research agenda to address current gaps in knowledge. The best evidence (grade A) is available for positive effects of calcium intake and physical activity, especially during the late childhood and peripubertal years-a critical period for bone accretion. Good evidence is also available for a role of vitamin D and dairy consumption and a detriment of DMPA injections. However, more rigorous trial data on many other lifestyle choices are needed and this need is outlined in our research agenda. Implementation strategies for lifestyle modifications to promote development of peak bone mass and strength within one's genetic potential require a multisectored (i.e., family, schools, healthcare systems) approach.

Reference values for digital X-ray radiogrammetry parameters in children and adolescents in comparison to estimates in patients with distal radius fractures

The first objective of this study was to determine normative digital X-ray radiogrammetry (DXR) values, based on original digital images, in a pediatric population (aged 6-18 years). The second aim was to compare these reference data with patients suffering from distal radius fractures, whereas both cohorts originated from the same geographical region and were evaluated using the same technical parameters as well as inclusion and exclusion criteria. DXR-BMD and DXR-MCI of the metacarpal bones II-IV were assessed on standardized digital hand radiographs, without printing or scanning procedures. DXR parameters were estimated separately by gender and among six age groups; values in the fracture group were compared to age- and gender-matched normative data using Student's t tests and Z scores. In the reference cohort (150 boys, 138 girls), gender differences were found in bone mineral density (DXR-BMD), with higher values for girls from 11 to 14 years and for boys from 15 to 18 years (p < 0.05). Girls had higher normative metacarpal index (DXR-MCI) values than boys, with significant differences at 11-14 years (p < 0.05). In the case-control investigation, the fracture group (95 boys, 69 girls) presented lower DXR-BMD at 15-18 years in boys and 13-16 years in girls vs. the reference cohort (p < 0.05); DXR-MCI was lower at 11-18 years in boys and 11-16 years in girls (p < 0.05). Mean Z scores in the fracture group for DXR-BMD were -0.42 (boys) and -0.46 (girls), and for DXR-MCI were -0.51 (boys) and -0.53 (girls). These findings indicate that the fully digital DXR technique can be accurately applied in pediatric populations ≥ 6 years of age. The lower DXR-BMD and DXR-MCI values in the fracture group suggest promising early identification of individuals with increased fracture risk, without the need for additional radiation exposure, enabling the initiation of prevention strategies to possibly reduce the incidence of osteoporosis later in life.

Bone and Spinal Muscular Atrophy

Spinal Muscular Atrophy (SMA) is an autosomal recessive neuromuscular disease, leading to progressive denervation atrophy in the involved skeletal muscles. Bone status has been poorly studied. We assessed bone metabolism, bone mineral density (BMD) and fractures in 30 children (age range 15-171 months) affected by SMA types 2 and 3. Eighteen children (60%) had higher than normal levels of CTx (bone resorption marker); 25-OH vitamin D was in the lower range of normal (below 20 ng/ml in 9 children and below 12 ng/ml in 2). Lumbar spine BMAD (bone mineral apparent density) Z-score was below -1.5 in 50% of children. According to clinical records, four children had sustained four peripheral fractures; on spine X-rays, we observed 9 previously undiagnosed vertebral fractures in 7 children. There was a significant inverse regression between PTH and 25-OH D levels, and a significant regression between BMC and BMAD values and the scores of motor-functional tests. Even if this study could not establish the pathogenesis of bone derangements in SMA, its main findings - reduced bone density, low 25OH vitamin D levels, increased bone resorption markers and asymptomatic vertebral fractures also in very young patients - strongly suggest that even young subjects affected by SMA should be considered at risk of osteopenia and even osteoporosis and fractures.

Peripheral quantitative computed tomography (pQCT) reveals low bone mineral density in adolescents with motor difficulties

This is the first reported study to describe local bone mineral density, assess parameters of fracture risk and report history of fractures in adolescents with motor difficulties. Motor difficulties evidenced by poor coordination in adolescence should be considered a new risk factor for below-average bone strength and structure and fracture risk.

INTRODUCTION

Adolescents with motor difficulties are characterised by poor coordination and low levels of physical activity and fitness. It is possible these deficits translate into below-average bone strength and structure. The objectives of this study were to describe local bone mineral density (BMD), assess parameters of fracture risk (stress-strain index, SSI) and report history of fractures in this group.

METHODS

Thirty-three adolescents (13 females), mean age of 14.3 (SD = 1.5) years, with motor difficulties underwent peripheral quantitative computed tomography (pQCT) measurements at proximal (66 %) and distal (4 %) sites of the non-dominant radius (R4 and R66) and tibia (T4 and T66). One sample t test was used to compare Z-scores for total BMD, trabecular density, cortical density and stress strain index (SSI) against standardized norms.

RESULTS

Significant differences were present at R4 total density mean Z-score = -0.85 (SD = 0.7, p < 0.001), R66 cortical density mean Z-score = -0.74 (SD = 1.97, p = 0.038), R66 SSI mean Z-score = -1.00 (SD = 1.08, p < 0.001) and T66 SSI mean Z-score = -0.70 (SD = 1.15, p < 0.001). There was a higher incidence of fractures (26.9 %) compared to the normal population (3-9 %).

CONCLUSIONS

Motor difficulties in adolescence should be considered a risk factor for below-average bone strength and structure and fracture risk. Strategies are needed to improve bone health in this high-risk-group.

Factors affecting bone mineral mass loss after lower-limb fractures in a pediatric population

BACKGROUND

The purpose of this study was to assess the effects of the durations of cast immobilization and non-weight-bearing periods, and decreases in vigorous physical activity (VPA) on bone mineral parameters in a pediatric population treated for a lower-limb fracture.

METHODS

Fifty children and teenagers who had undergone a cast-mediated immobilization for a leg or ankle fracture were prospectively recruited. The durations of cast immobilization and non-weight-bearing periods were recorded for each participant. Dual-energy x-ray absorptiometry scans were performed at the time of fracture treatment (baseline) and at cast removal. Physical activity during cast immobilization was assessed using accelerometers.

RESULTS

A strong negative correlation was found between the total duration of cast immobilization and decreases in both calcaneal bone mineral density (BMD) (r=-0.497) and total lower-limb bone mineral content (BMC) (r=-0.405). A strong negative correlation was also noted between the durations of the non-weight-bearing periods and alterations in calcaneal BMD (r=-0.420). No apparent correlations were found between lower BMD and BMC and decreased VPA.

CONCLUSIONS

Bone mineral loss was correlated to the total duration of cast immobilization for all measurement sites on the affected leg, whereas it was only correlated to the durations of non-weight-bearing periods for calcaneal BMD and total lower-limb BMC. However, no correlations were noted between bone mineral loss and decreased VPA.

Bone density in children with single ventricle physiology

Children with chronic diseases are at risk for low bone mineral density (BMD). There are no studies of BMD in children with congenital heart disease and particularly single ventricle (SV). Children with this defect are often treated with warfarin, suspected to negatively impact BMD in adults. We assessed BMD in patients with SV physiology and compared the BMD of subjects taking warfarin to those who were not. Subjects 5-12 years with SV were included. BMD z scores by dual-energy X-ray absorptiometry of the spine and total body less head (TBLH) were obtained. Calcium intake, activity level, height, and Tanner stage were assessed. Linear regression models and t tests were used to investigate differences between participants and normative data as well as between subjects' subgroups. Twenty-six subjects were included and 16 took warfarin. Mean BMD z score at the spine was significantly lower than expected at -1.0 ± 0.2 (p < 0.0001), as was the BMD z score for TBLH at -0.8 ± 0.2 (p < 0.0001). Those results remained significant after adjusting for height. Subjects who were on warfarin tended to have lower BMD at both the spine and TBLH than those who were not, with a z score difference of 0.6 ± 0.46 at the spine (p = 0.106) and a difference of 0.4 ± 0.34 at TBLH (p = 0.132). BMD is significantly reduced in children with SV. Warfarin appears to lower BMD but the effect is less conclusive. Continued evaluation is recommended for these patients at risk for reduced bone density. Evaluation of other cardiac patients on warfarin therapy should also be considered.

DXA-based variables and osteoporotic fractures in Lebanese postmenopausal women

INTRODUCTION

The aim of this study was to assess DXA-based variables (bone mineral density, bone mineral apparent density, compressive strength index of the femoral neck and trabecular bone score) in Lebanese postmenopausal women having presented a previous fracture.

MATERIALS AND METHODS

One thousand Lebanese postmenopausal women between 45 and 89 years participated in this study. The women were recruited by advertisements offering bone mineral density measurements at a reduced cost. Subjects with previous history of radiotherapy or chemotherapy were excluded. Informed written consent was obtained from all the participants.

RESULTS

Femoral neck compressive strength index (FN CSI) was significantly (P<0.001) associated with the presence of fracture using a simple logistic regression (odds ratio=0.51 [0.385-0.653]). When a multivariate logistic regression analysis was performed with the presence of fracture as a dependent variable and each of age, FN BMD and FN CSI as independent variables, only FN BMD (P=0.005) and FN CSI (P=0.004) were found to be associated with the presence of fracture.

CONCLUSION

This study suggests that FN CSI is associated with history of osteoporotic fractures in postmenopausal women. The use of FN CSI in clinical practice may help to identify patients with high risk of fracture.

LEVEL OF EVIDENCE

Epidemiological study, level IV.

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.

Bone Mineral Density in Children From Anthropological and Clinical Sciences: A Review

Bone mineral density (BMD) is a frequent topic of discussion in the clinical literature in relation to the bone health of both adults and children. However, in archaeological and/ or anthropological studies the role of BMD is often cited as a possible factor in the poor skeletal preservation which can lead to an under-representation of juvenile skeletal remains. During skeletal development and growth throughout childhood and adolescence changes take place in both the size and shape of bones and these changes also result in the increasing of mineral content. BMD can be affected by many factors, which include, age, genetics, sexual maturation, amount of physical activity and dietary calcium. This paper aims to review the clinical and anthropological literature on BMD and discuss the numerous methods of measurement and how the availability of certain methods such as Dual-energy x-ray absorptiometry (DEXA) and quantitative computed tomography (QCT) can influence the study of bone density in archaeological skeletal collections and also the future potential for forensic anthropological studies.

Bone fractures in children with autistic spectrum disorder

BACKGROUND

Bone fractures in children represent a source of significant disability and morbidity. Are children with autistic spectrum disorder (ASD) at an altered risk of fractures compared with typically developing children?

METHODS

Using the General Practice Research Database, the authors assessed the prevalence of fractures in boys with ASD diagnosed between 2 and 8 years. A cross-sectional design was used to compare the prevalence of fractures among children with ASD and age-matched controls, conditional logistic regression to explore the relative risk of having a fracture in association with diagnosed ASD.

RESULTS

The study population comprised 3,219 boys with a first-time diagnosis of ASD and 12,265 matched controls. ASD was associated with a significantly decreased risk of developing a fracture at any time in childhood (odds ratio [OR], 0.68, 95% confidence interval [CI], 0.59-0.77, p < .0001). The relative risk estimates were lower for the time period after ASD diagnosis (OR, 0.56, 95% CI, 0.48-0.66, p < .0001) but were not different for the time period before ASD diagnosis (OR, 0.96, 95% CI, 0.78-1.18, p = .6866). Adjusting for use of different drugs did not change the estimates.

CONCLUSION

The relative risk of experiencing a fracture at any time in childhood is lower for boys with ASD compared with healthy boys.

The association between fracture rates and neighborhood characteristics in Washington, DC, children

BACKGROUND

Effects of neighborhood contextual features have been found for many diseases, including bone fractures in adults. Our study objective was to evaluate the association between neighborhood characteristics and pediatric bone fracture rates. We hypothesized that neighborhood indices of deprivation would be associated with higher fracture rates.

MATERIALS AND METHODS

Pediatric bone fracture cases treated at a tertiary, academic, urban pediatric emergency department between 2003 and 2006 were mapped to census block groups using geographical information systems software. Fracture rates were calculated as fractures per 1000 children in each census block. Exploratory factor analysis of socioeconomic indicators was performed using 2000 census block data. Factor scores were used to predict odds of bone fracture at the individual level while adjusting for mean age, sex composition, and race/ethnicity composition at census block level using our sample data.

RESULTS

We analyzed 3764 fracture visits in 3557 patients representing 349 distinct census blocks groups. Fracture rates among census blocks ranged from 0 to 207 per 1000 children/study period. Logistic regression modeling identified 2 factors (race/education and large families) associated with increased fracture risk. Census variables reflecting African American race, laborer/service industry employment, long-term block group residence, and lower education levels strongly loaded on the race/education factor. The large families factor indicated the children-to-families ratio within the block group. The poverty factor was not independently associated with fracture risk.

CONCLUSIONS

Thus, neighborhood characteristics are associated with risk for fractures in children. These results can help inform translational efforts to develop targeted strategies for bone fracture prevention in children.

Vitamin D deficiency among children with epilepsy in South Queensland

This study evaluated prevalence and risk factors for vitamin D deficiency among children with epilepsy on long-term antiepileptic drugs treated in South Queensland, Australia. Children with epilepsy seen in a tertiary neurology clinic were contacted requesting bone health blood tests during winter of 2011. Vitamin D deficiency was defined as 25-hydroxy vitamin D levels <20 ng/mL, and insufficiency between 21 and 29 ng/mL. One hundred thirty letters were sent, with 111 (85%) subsequently having blood tests performed. Vitamin D deficiency was identified in 24 (22%) of 111 and an additional 45 (41%) of 111 had vitamin D insufficiency. Multiple logistic regression analysis identified children on >2 antiepileptic drugs or with underlying genetic etiologies were more likely to have vitamin D deficiency. High proportion of children on long-term antiepileptic drugs in Queensland risk vitamin D deficiency and insufficiency despite living in the subtropics. Vitamin D monitoring and supplementation is important in the management of children on long-term antiepileptic drugs requiring tertiary care in Queensland.

Obesity and its effects on pediatric supracondylar humeral fractures

BACKGROUND

This study evaluates the effects of childhood obesity on fracture complexity and associated injuries in pediatric supracondylar humeral fractures.

METHODS

A billing query identified all patients who were two to eleven years of age and had undergone operative treatment for extension-type supracondylar humeral fractures over a 12.5-year period. Records were reviewed for demographic data, body mass index percentile, and injury data. Complex fractures were defined as type-3 supracondylar humeral fractures, supracondylar humeral fractures with intercondylar extension, or supracondylar humeral fractures with ipsilateral upper-extremity fractures. Logistic regression analyses were used to test relationships among body mass index subgroups, fracture complexity, elbow motion, preoperative and postoperative neurovascular status, and complications.

RESULTS

Three hundred and fifty-four patients met our inclusion criteria. Forty-one children were underweight (BMI in the <5th percentile), 182 were normal weight (BMI in the 5th to 85th percentile), sixty-three were overweight (BMI in the >85th to 95th percentile), and sixty-eight were obese (BMI in the >95th percentile). There were 149 patients, eleven of whom were obese, with isolated type-2 fractures and 205 patients, fifty-seven of whom were obese, with complex fractures. Thirty-two patients had preoperative nerve palsies and twenty-eight patients had postoperative nerve palsies. Using logistic regression, obesity was associated with complex fractures (odds ratio, 9.19 [95% confidence interval, 4.25 to 19.92]; p < 0.001), preoperative nerve palsies (odds ratio, 2.69 [95% confidence interval, 1.15 to 6.29]; p = 0.02), postoperative nerve palsies (odds ratio, 7.69 [95% confidence interval, 2.66 to 22.31]; p < 0.001), and postoperative complications (odds ratio, 4.03 [95% confidence interval, 1.72 to 9.46]; p < 0.001). Additionally, obese patients were more likely to sustain complex fractures from a fall on an outstretched hand than normal-weight patients (odds ratio, 13.00 [95% confidence interval, 3.44 to 49.19]; p < 0.001).

CONCLUSIONS

Obesity is associated with more complex supracondylar humeral fractures, preoperative and postoperative nerve palsies, and postoperative complications. To our knowledge, this study is the first to assess the implications of obesity on supracondylar humeral fracture complexity and associated injuries and it validates public health efforts in combating childhood obesity.

Fracture patterns and bone mass in South African adolescent-mother pairs: the Birth to Twenty cohort

The associations of fracture prevalence and bone mass in adolescents with maternal fracture history and bone mass have not been investigated previously in South Africa. Maternal bone mass has a significant inverse association with their adolescents' fracture rates and bone mass across all ethnic groups.

INTRODUCTION

Differences in fracture rates and bone mass between families and individuals of different ethnic origins may be due to differing lifestyles and/or genetic backgrounds. This study aimed to assess associations of fracture prevalence and bone mass in adolescents with maternal fracture history and bone mass, and sibling fracture history.

METHODS

Data from 1,389 adolescent-biological mother pairs from the Birth to Twenty longitudinal study were obtained. Questionnaires were completed on adolescent fractures until 17/18 years of age and on sibling fractures. Biological mothers completed questionnaires on their own fractures prior to the age of 18 years. Anthropometric and bone mass data on adolescent-biological mother pairs were collected.

RESULTS

An adolescent's risk of lifetime fracture decreased with increasing maternal lumbar spine (LS) bone mineral content (BMC; 24 % reduction in fracture risk for every unit increase in maternal LS BMC Z-score) and increased if they were white, male, or had a sibling with a history of fracture. Adolescent height, weight, male gender, maternal bone area and BMC, and white ethnicity were positive predictors of adolescent bone mass. White adolescents and their mothers had a higher fracture prevalence (adolescents 42 %, mothers 31 %) compared to the black (adolescents 20 %, mothers 6 %) and mixed ancestry (adolescents 20 %, mothers 16 %) groups.

CONCLUSION

Maternal bone mass has a significant inverse association with their adolescent off-springs' fracture risk and bone mass. Furthermore, there is a strong familial component in fracture patterns among South African adolescents and their siblings.

Effects of weight-bearing activities on bone mineral content and density in children and adolescents: a meta-analysis

Osteoporosis and associated fractures are a major health concern in Western industrialized nations. Exercise during growth is suggested to oppose the involutional bone loss later in life by increasing peak bone mass. The primary aim of the present meta-analysis was to provide a robust estimate of the effect of weight-bearing activities (WBAs) on bone mineral content (BMC) and areal bone mineral density (aBMD), during childhood and adolescence. To locate relevant studies up to June 2012, computerized searches of multiple bibliographic databases and hand searches of key journals and reference lists were performed. Results were extracted by two independent reviewers. The quality of the included trials was assessed via the Physiotherapy Evidence Database (PEDro) score. The study group effect was defined as the difference between the standardized mean change for the treatment and control groups divided by the pooled pretest SD. From 109 potentially relevant studies, only 27 met the inclusion criteria. The analyzed training programs were capable of significantly increasing BMC and aBMD during growth. However, the weighted overall effect sizes (ESs) for changes in BMC (ES 0.17; 95% confidence interval [CI], 0.05-0.29; p < 0.05) and aBMD (ES 0.26; 95% CI, 0.02-0.49) were small. Stepwise backward regression revealed that more than one-third of the observed variance (r(2)  = 0.35) between subgroups of the BMC dataset could be explained by differences in the amount of habitual calcium intake per day (beta 0.54, p < 0.01) and the maturational stage (beta -0.28, p < 0.01) at baseline. No significant moderators were identified for aBMD, possibly due to the small number of trials investigating WBAs on aBMD. The results of this meta-analysis conclude that WBAs alongside high calcium intake provide a practical, relevant method to significantly improve BMC in prepubertal children, justifying the application of this exercise form as an osteoporosis prophylaxis in this stage of maturity.

A distal forearm fracture in childhood is associated with an increased risk for future fragility fractures in adult men, but not women

Distal forearm fractures are among the most common fractures during childhood, but it remains unclear whether they predict an increased fracture risk later in life. We studied a population-based cohort of 1776 children ≤18 years of age, from Olmsted County, MN, USA, who had a distal forearm fracture in 1935-1992. Incident fractures occurring at age ≥35 years were identified through review of complete medical records using the linkage system of the Rochester Epidemiology Project. Observed nonpathologic fractures resulting from no more than moderate trauma (fragility fractures) were compared with expected numbers estimated from fracture site-specific incidence rates, based on age, sex, and calendar year, for Olmsted County (standardized incidence ratios [SIR]). In 1086 boys (mean ± SD age; 11 ± 4 years) and 690 girls (10 ± 4 years) followed for 27,292 person-years after the age of 35 years, subsequent fragility fractures were observed in 144 (13%) men and 74 (11%) women. There was an increased risk for future fragility fractures in boys who had a distal forearm fracture (SIR, 1.9; 95% CI, 1.6-2.3) but not girls (SIR, 1.0; 95% CI, 0.8-1.2). Fragility fractures at both major osteoporotic (hip, spine, wrist, and shoulder) sites (SIR, 2.6; 95% CI, 2.1-3.3) and remaining sites (SIR, 1.7; 95% CI, 1.3-2.0) were increased in men, irrespective of age at distal forearm fracture as boys. A distal forearm fracture in boys, but not girls, is associated with an increased risk for fragility fractures as older adults. It is necessary to determine whether the increased fractures observed in men is due to persistent deficits of bone strength, continued high fracture risk activity, or both. Until then, men should be asked about a childhood distal forearm fracture and, if so, warrant further screening and counseling on measures to optimize bone health and prevent fractures.

Recovery of decreased bone mineral mass after lower-limb fractures in adolescents

BACKGROUND

Loss of bone mineral mass, muscle atrophy, and functional limitations are predictable consequences of immobilization and subsequent weight-bearing restriction due to leg or ankle fractures. The aim of this study was to prospectively determine whether decreased bone mineral mass following lower-limb fractures recovers at follow-up durations of six and eighteen months in adolescents.

METHODS

In the present study, we included fifty adolescents who underwent cast immobilization for a leg or ankle fracture. Dual x-ray absorptiometry scans of four different sites (total hip, femoral neck, entire lower limb, and calcaneus) were performed at the time of the fracture, at cast removal, and at follow-ups of six and eighteen months. Patients with fractures were paired with healthy controls according to sex, age, and ethnicity. Dual x-ray absorptiometry values were compared between groups and between injured and non-injured legs in adolescents with fractures.

RESULTS

Among those with fractures, lower-limb bone mineral variables were significantly lower at the injured side compared with the non-injured side at cast removal, with differences ranging from 6.2% to 31.7% (p &lt; 0.0001). Similarly, injured adolescents had significantly lower bone mineral values at the level of the injured lower limb compared with healthy controls (p &lt; 0.0001). At the six-month follow-up, there were still significant residual differences between injured and non-injured legs in adolescents with fractures (p &lt; 0.0001). However, a significant residual difference between healthy controls and injured adolescents was present only for femoral neck bone mineral density (p = 0.011). At the eighteen-month follow-up, no significant difference was observed at any lower-limb site.

CONCLUSIONS

Bone mineral loss following a fracture of the lower limb in adolescents is highly significant and affects the lower limb both proximal to and distal to the fracture site. In contrast to observations in adults, a rapid bone mass reversal occurs with full bone recovery by eighteen months.

LEVEL OF EVIDENCE

Prognostic Level I. See Instructions for Authors for a complete description of levels of evidence.

The association between breastfeeding, maternal smoking in utero, and birth weight with bone mass and fractures in adolescents: a 16-year longitudinal study

The aim of this birth cohort study was to determine whether early life factors (birth weight, breastfeeding, and maternal smoking) were associated with bone mass and fractures in 16-year-old adolescents. The results suggest that breastfeeding is associated with higher bone mass and lower fracture risk at age 16 but not in utero smoking or birth weight.

INTRODUCTION

There are limited data on early life influences on bone mass in adolescence but we have previously reported in utero smoking, breastfeeding, and birth weight were associated with bone mass at age 8.

METHODS

Birth weight, breastfeeding intention and habit, and maternal smoking during pregnancy were assessed at phase one in 1988-1999 and by recall during phase two in 1996-1997. Bone mineral density (BMD) was measured by dual-energy X-ray densitometry. Fractures were assessed by questionnaire. Subjects included 415 male and female adolescents from Southern Tasmania representing 29 % of those who originally took part in a birth cohort study in 1988 and 1989.

RESULTS

Breastfeeding (assessed in a number of ways) was associated with a 2-3 % increase in BMD at all sites apart from the radius and around a one third reduction in fracture risk which persisted after adjustment for confounders. In univariate analysis, birth weight was associated with BMD at the hip, radius, and total body but this did not persist in multivariate analysis and there was no association with fracture. Smoking in utero had no association with BMD at any site or fracture.

CONCLUSIONS

Breastfeeding is associated with a beneficial increase in bone mass at age 16 and a reduction in fracture risk during adolescence. The association previously observed at 8 years of age is no longer present for birth weight or smoking in utero.

Factors associated with low bone density in patients referred for assessment of bone health

Background

To identify factors that predict low bone mineral density (BMD) in pediatric patients referred for dual-energy x-ray absorptiometry assessments.

Methods

This is a retrospective cohort study of 304 children and adolescents referred for dual-energy x-ray absorptiometry assessments at a tertiary care center. Outcomes included risk factors which predicted a significant low bone density for age, defined as BMD Z-score ≤ -2.0 SD. A univariate analysis involved Chi-square, Fisher’s Exact test, and analysis of variance, and multivariate logistic regression models were constructed to determine predictors of low bone mineral density.

Results

In the multivariate logistic regression model, predictors of low bone mineral density included low body mass index Z-score (odds ratio 0.52, 95% confidence interval 0.39 – 0.69), low height Z-score (OR 0.71, 95% CI 0.57 – 0.88), vitamin D insufficiency (OR 3.97, 95% CI 2.08 – 7.59), and history of bone marrow transplant (OR 5.78, 95% CI 1.00 – 33.45).

Conclusions

Underlying health problems and associated treatments can impair bone mineral accrual. We identified risk factors most predictive of low bone mineral density in subjects referred for bone density measurement. Recognition of these factors may allow for earlier assessment to maximize bone mass in at-risk children.

Does a childhood fracture predict low bone mass in young adulthood? A 27-year prospective controlled study

A fracture in childhood is associated with low bone mineral density (BMD), but it is debated whether a fracture at growth also predicts low BMD in young adulthood. The purpose of this work was to gender-specifically evaluate whether children with a fracture are at increased risk of low BMD in young adulthood. Distal forearm BMD (g/cm2) was measured with single-photon absorptiometry (SPA) in 47 boys and 26 girls (mean age 10 years, range 3-16 years) with an index fracture and in 41 boys and 43 girls (mean age 10 years, range 4-16 years) with no fracture. BMD was re-measured mean 27 years later with the same SPA apparatus and with dual-energy absorptiometry (DXA), quantitative ultrasound (QUS), and peripheral computed tomography (pQCT). Individual Z-scores were calculated using the control cohort as reference population. Data are presented as means with 95% confidence intervals (95% CI) within brackets and correlation with Pearson's correlation coefficient. Boys with an index fracture had at fracture event a distal forearm BMD Z-score of -0.4 (95% CI, -0.7 to -0.1) and at follow-up -0.4 (95% CI, -0.7 to -0.1). Corresponding values in girls were -0.2 (95% CI, -0.5 to 0.1) and -0.3 (95% CI, -0.7 to 0.1). The deficit in absolute bone mass was driven by men with index fractures in childhood due to low energy rather than moderate or high energy. There were no changes in BMD Z-score during the follow-up period. The BMD deficit at follow-up was in boys with an index fracture verified with all advocated techniques. A childhood fracture in men was associated with low BMD and smaller bone size in young adulthood whereas the deficit in women did not reach statistical significance.

Vitamin D and bone health in childhood and adolescence

Vitamin D plays a key role in bone metabolism. The link between vitamin D deficiency and rickets is well understood. However, subclinical vitamin D deficiency may also be detrimental to bone health in childhood. Its effects on bone mineralization have the potential to result in lower peak bone mass being attained, which could in turn contribute to increased fracture risk in both childhood and older adult life. As vitamin D deficiency is common globally, any detrimental effects of vitamin D deficiency on bone health are likely to have substantial public health implications. This review describes the current literature relevant to vitamin D and bone health in childhood and adolescence, with a particular emphasis on evaluating the emerging evidence for the impact of subclinical vitamin D deficiency on bone health and the effectiveness of vitamin D supplementation. The evidence suggests that subclinical vitamin D deficiency does affect bone acquisition, potentially beginning in utero and extending into adolescence. However, the effectiveness of vitamin D supplementation for improving bone health in situations of subclinical deficiency remains unclear, particularly in early life where there are few trials with bone density outcomes. The available evidence suggests that benefits are likely to be greatest in or even restricted to children with serum 25-hydroxyvitamin D levels at least below 50 nmol/L and possibly even lower than this. Trials of sufficient duration in deficient pregnant mothers, infants, and children are urgently required to address critical evidence gaps.

Correlation between bone mineral density measured by peripheral and central dual energy X-ray absorptiometry in healthy Indian children and adolescents aged 10-18 years

There are few large-scale studies on the utility of peripheral dual energy X-ray absorptiometry (pDXA) in children. As central dual energy X-ray absorptiometry (cDXA) equipment is not commonly available in the developing world, we assessed the correlation of bone mineral density (BMD) with cDXA and pDXA in children to determine the optimal Z-score thresholds of pDXA for predicting two predefined Z-score cutoffs (≤-1, ≤-2) of cDXA in 844 subjects (441 boys, 403 girls) aged 10-18 years. The BMD of antero-posterior lumbar spine (L1-L4), proximal femur and forearm was measured by cDXA, while the peripheral BMD of forearm and calcaneus was estimated using pDXA. The correlation was statistically significant at all sites (p<0.01). The coefficients ranged from 0.56 to 0.79 in boys and 0.17 to 0.32 in girls. A significant positive correlation was observed between BMD by pDXA and cDXA in Indian children, with a strong gender difference in both the extent of correlation and the ability of peripheral BMD to predict central BMD.

Prevalence of vitamin D insufficiency in Swiss teenagers with appendicular fractures: a prospective study of 100 cases

BACKGROUND

The significance of subclinical vitamin D deficiency in the pathogenesis of fractures in children and adolescents currently remains unclear.

OBJECTIVE

We aimed to determine the prevalence of vitamin D insufficiency and its effect on bone mineral density (BMD) and bone mineral content (BMC) values in a collective of Swiss Caucasian children with a first episode of appendicular fracture.

DESIGN AND METHODS

One hundred teenagers with a first episode of appendicular fracture [50 upper limb fractures (group 1) and 50 lower limb fractures (group 2)] and 50 healthy controls (group 3) were recruited into a cross-sectional study. The BMC and BMD values were measured by dual-energy X-ray absorptiometry, and serum 25 hydroxyvitamin D [25(OH)D] was assessed by electrochemiluminescence immunoassays.

RESULTS

From the 100 injured teenagers in the study, 12 % had deficient vitamin D levels (<20 ng/mL; <50 nmol/L) and 36 % had insufficient levels (≥20 <30 ng/mL; ≥50 <78 nmol/L), whereas 6 and 34 % of healthy controls were, respectively, vitamin D deficient and insufficient. There were no significant differences for serum 25(OH)D levels, L2-L4 BMD Z-score, and L2-L4 BMC Z-score variables (p = 0.216) between the three groups nor for the calcaneal BMD Z-score variables (p = 0.278) between healthy controls and lower limb fracture victims. Investigations on the influences of serum 25(OH)D on BMD and BMC showed no correlation between serum 25(OH)D and L2-L4 BMD Z-scores (r = -0.15; p = 0.135), whereas low but significant inverse correlations were, surprisingly, detected between serum 25(OH)D and calcaneal BMD Z-scores (r = -0.21; p = 0.034) and between serum 25(OH)D and L2-L4 BMC Z-scores (r = -0.22; p = 0.029).

CONCLUSIONS

A significant proportion of Swiss Caucasian teenagers were vitamin D insufficient, independent of limb fracture status, in our study. However, this study failed to show an influence of low vitamin D status on BMD and/or BMC of the lumbar spine and heel.

Bone mineral density and vitamin D status among African American children with forearm fractures

OBJECTIVE

To determine whether African American children with forearm fractures have decreased bone mineral density and an increased prevalence of vitamin D deficiency (serum 25-hydroxyvitamin D level ≤ 20 ng/mL) compared with fracture-free control patients.

METHODS

This case-control study in African American children, aged 5 to 9 years, included case patients with forearm fracture and control patients without fracture. Evaluation included measurement of bone mineral density and serum 25-hydroxyvitamin D level. Univariable and multivariable analyses were used to test for associations between fracture status and 2 measures of bone health (bone mineral density and 25-hydroxyvitamin D level) while controlling for other potential confounders.

RESULTS

The final sample included 76 case and 74 control patients. There were no significant differences between case and control patients in age, gender, parental education level, enrollment season, outdoor play time, height, or mean dietary calcium nutrient density. Cases were more likely than control patients to be overweight (49.3% vs 31.4%, P = .03). Compared with control patients, case patients had lower whole body z scores for bone mineral density (0.62 ± 0.96 vs 0.98 ± 1.09; adjusted odds ratio 0.38 [0.20-0.72]) and were more likely to be vitamin D deficient (47.1% vs 40.8%; adjusted odds ratio 3.46 [1.09-10.94]).

CONCLUSIONS

These data support an association of lower bone mineral density and vitamin D deficiency with increased odds of forearm fracture among African American children. Because suboptimal childhood bone health also negatively impacts adult bone health, interventions to increase bone mineral density and correct vitamin D deficiency are indicated in this population to provide short-term and long-term benefits.