Prediction of adult height based on automated determination of bone age

Use of the Ultrasound Bone Maturity Indexes to Assess Whether Children Have Reached Their Final Height

OBJECTIVE

Ultrasound bone maturity indexes were used to assess whether children had reached their final height.

METHODS

The follow-up study was performed between January 2022 and August 2024. Ultrasound bone maturity indexes, including the ossification ratio of the radius, ulna, and femur, and skeletal maturity score (SMS, the sum of the ossification ratio of the above three bones multiplied by 100), were collected from medical records, along with the children's age and height. The children were followed up to ascertain the annual increase in height during the 2 years before and after the ultrasound bone age assessment. Children were grouped according to whether they had reached their final height. The diagnostic performance (area under the curve, AUC) of ultrasound bone maturity indexes in assessing whether the children had reached their final height was confirmed.

RESULTS

A total of 120 children (60 boys) with a mean age of 15.0 ± 1.7 years for boys and 14.1 ± 2.0 years for girls were included. At the attainment of final height, the mean values of radial, ulnar, and femoral ossification ratios, as well as the SMS, were 90%, 84%, 98%, and 271 in boys and 86%, 83%, 98%, and 267 in girls, respectively. Ultrasound bone maturity indexes were able to assess whether children had reached their final height, with the highest AUC for SMS of 0.99 (95% CI: 0.97, 1.01, cutoff value, 256) in boys and 0.95 (95% CI: 0.90, 1.00, cutoff value, 260) in girls.

CONCLUSION

A child's height stops increasing before the ossification ratios of the bones reach 100%. Ultrasound bone maturity indexes, especially SMS, demonstrate high diagnostic performance in determining whether children have reached their final height.

Loss-of-Function GHSR Variants Are Associated With Short Stature and Low IGF-I

CONTEXT

The growth hormone (GH) secretagogue receptor, encoded by GHSR, is expressed on somatotrophs of the pituitary gland. Stimulation with its ligand ghrelin, as well as its constitutive activity, enhances GH secretion. Studies in knockout mice suggest that heterozygous loss-of-function of GHSR is associated with decreased GH response to fasting, but patient observations in small case reports have been equivocal.

OBJECTIVE

This work aims to establish the phenotype of GHSR haploinsufficiency and its growth response to GH treatment.

METHODS

This case series includes 26 patients with short stature and heterozygous GHSR variants. Pathogenicity was studied in vitro using total protein levels, cell surface expression, and receptor activity in basal, stimulated, and inhibited states.

RESULTS

Ten different variants were identified, of which 6 were novel. Variants showed either partial or complete loss of function, primarily through loss of constitutive activity. Patients (aged 4.0-15.1 years) had proportionate short stature (height -2.8 ± 0.5 SDS), failure to thrive with low appetite (n = 4), a mean serum insulin-like growth factor-I (IGF-I) of -1.6 ± 0.7 SDS, and a normal stimulated GH response. Nine patients received GH treatment, showing a height gain of 0.9 ± 0.4 SDS after 1 year and 1.5 ± 0.4 SDS after 2 years (n = 5).

CONCLUSION

This study combines phenotypical and functional data in a uniquely large group of children with short stature carrying GHSR variants, and shows their good response to GH treatment. The results strengthen the hypothesis of GHSR's role in GH secretion.

Association between bone age maturity and childhood adiposity

BACKGROUND

Evidence shows that overweight and obesity are associated with advanced bone age (BA).

OBJECTIVE

To analyse the effect of adiposity on BA among Mexican children.

METHODS

This cross-sectional study included 902 children (5-18 years old). Anthropometric measurements, dual-energy X-ray absorptiometry (DXA) and automated hand X-ray-based BA measurements were obtained. BA curves of children stratified by sex and age were created based on nutritional status. We also calculated odds ratios for advanced BA associated with the body mass index (BMI), waist/height ratio and adiposity estimated using DXA (total and truncal fat mass).

RESULTS

Participants with overweight/obesity by BMI (SDS ≥1) advanced earlier in BA than did normal weight participants (6.0 vs. 12.0 years in boys and 6.0 vs. 10.3 in girls, p < 0.01); similarly, participants with a greater body fat percentage (SDS ≥1) exhibited earlier advanced BA (7.5 vs. 10.0 years in boys and 6.0 vs. 9.6 in girls, p < 0.01). Differences were also observed according to the waist/height ratio and truncal fat. Children with a BMI or DXA SDS ≥1 had greater odds of presenting an advanced BA of more than 1 year (OR 1.79-3.55, p < 0.05).

CONCLUSIONS

Increased adiposity in children, mainly in boys, is associated with advanced BA at earlier ages.

IGF1 Haploinsufficiency: Phenotype and Response to Growth Hormone Treatment in 9 Patients

INTRODUCTION

The clinical features of bi-allelic IGF1 defects are well established, i.e., severe growth failure and microcephaly, delayed psychomotor development, and sensorineural deafness. However, information on clinical and endocrine consequences of heterozygous IGF1 variants and treatment options is scarce. We aimed at extending the knowledge base of the clinical presentation and growth response to recombinant human growth hormone (rhGH) of patients carrying such variants.

METHODS

Retrospective case series of patients with pathogenic heterozygous IGF1 variants.

RESULTS

Nine patients from six families were included, harbouring five whole or partial gene deletions and one frameshift variant resulting in a premature stop codon (three de novo, one unknown inheritance). In the other two families, variants segregated with short stature. Mean (SD) birth length was -1.9 (1.3) SDS (n = 7), height -3.8 (0.6) SDS, head circumference -2.5 (0.6) SDS, serum IGF-I -1.9 (0.7) SDS, serum IGFBP-3 1.1 (0.4) SDS (n = 7), and GH peak range 5-31 μg/L (n = 4). Five patients showed feeding problems in infancy. Average height increased after 1 and 2 years of rhGH treatment by 0.8 SDS (range 0.3-1.3 SDS) and 1.3 SDS (range 0.5-2.0 SDS), respectively. Adult height in 2 patients was -2.8 and -1.3 SDS, which was, respectively, 1.3 and 2.9 SDS taller than predicted before start of treatment.

CONCLUSION

Haploinsufficiency of IGF1 causes a variable phenotype of prenatal and postnatal growth failure, microcephaly, feeding difficulties, low/low-normal serum IGF-I values in contrast to serum IGFBP-3 in the upper-normal range. Treatment with rhGH increased growth in the first 2 years of treatment, and in 2 patients adult height after treatment was higher than predicted at treatment initiation.

Association of ZBTB38 gene polymorphism (rs724016) with height and fetal hemoglobin in individuals with sickle cell anemia

Objectives

Our study evaluated the association of the polymorphism rs724016 in the ZBTB38 gene, previously associated with height in other populations, with predictors of height, clinical outcomes, and laboratory parameters in sickle cell anemia (SCA).

Methods

Cross-sectional study with individuals with SCA and aged between 3 and 20 years. Clinical, laboratory, molecular, and bone age (BA) data were evaluated. Levels of IGF-1 and IGFBP-3 were adjusted for BA, target height (TH) was calculated as the mean parental height standard deviation score (SDS), and predicted adult height (PAH) SDS was calculated using BA.

Results

We evaluated 80 individuals with SCA. The homozygous genotype of the G allele of rs724016 was associated with a lower height SDS (p < 0.001) and, in a additive genetic model, was negatively associated with HbF levels (p = 0.016). Lower adjusted IGF-1 levels were associated with co-inheritance of alpha-thalassemia and with the absence of HU therapy. Elevated HbF levels were associated with a lower deficit in adjusted growth potential (TH minus PAH).

Conclusion

Our analysis shows that SNP rs724016 in the ZBTB38 is associated with shorter height and lower HbF levels, an important modifier of SCA.

Secular trends in physical growth, biological maturation, and intelligence in children and adolescents born between 1978 and 1993

Introduction

Human physical growth, biological maturation, and intelligence have been documented as increasing for over 100 years. Comparing the timing of secular trends in these characteristics could provide insight into what underlies them. However, they have not been examined in parallel in the same cohort during different developmental phases. Thus, the aim of this study was to examine secular trends in body height, weight, and head circumference, biological maturation, and intelligence by assessing these traits concurrently at four points during development: the ages of 4, 9, 14, and 18 years.

Methods

Data derived from growth measures, bone age as an indicator of biological maturation, and full-scale intelligence tests were drawn from 236 participants of the Zurich Longitudinal Studies born between 1978 and 1993. In addition, birth weight was analyzed as an indicator of prenatal conditions.

Results

Secular trends for height and weight at 4 years were positive (0.35 SD increase per decade for height and an insignificant 0.27 SD increase per decade for weight) and remained similar at 9 and 14 years (height: 0.46 SD and 0.38 SD increase per decade; weight: 0.51 SD and 0.51 SD increase per decade, respectively) as well as for weight at age 18 years (0.36 SD increase per decade). In contrast, the secular trend in height was no longer evident at age 18 years (0.09 SD increase per decade). Secular trends for biological maturation at 14 years were similar to those of height and weight (0.54 SD increase per decade). At 18 years, the trend was non-significant (0.38 SD increase per decade). For intelligence, a positive secular trend was found at 4 years (0.54 SD increase per decade). In contrast, negative secular trends were observed at 9 years (0.54 SD decrease per decade) and 14 years (0.60 SD decrease per decade). No secular trend was observed at any of the four ages for head circumference (0.01, 0.24, 0.17, and - 0.04 SD increase per decade, respectively) and birth weight (0.01 SD decrease per decade).

Discussion

The different patterns of changes in physical growth, biological maturation, and intelligence between 1978 and 1993 indicate that distinct mechanisms underlie these secular trends.

Central precocious puberty in boys: secular trend and clinical features

OBJECTIVE

Recent studies suggest that boys enter puberty at a younger age, and the incidence of male central precocious puberty (CPP) is increasing. In this study, we explore the incidence of male CPP and identify key clinical and auxological indicators for organic CPP (OCPP).

DESIGN

A retrospective registry-based study.

METHODS

The medical records of 43 boys treated with CPP at the Helsinki University Hospital between 1985 and 2014 were reviewed. Clinical, auxological, and endocrine data of the CPP patients were included in the analyses.

RESULTS

Based on brain MRI, 26% of patients had OCPP. Between 2010 and 2014, the CPP incidence in boys was 0.34 per 10 000 (95% CI 0.20-0.60). Between 1990 and 2014, the male CPP incidence increased (incidence rate ratio [IRR] 1.10, P = .001). This increase was driven by rising idiopathic CPP (ICPP) incidence (IRR 1.11, 95% CI 1.05-1.19, P < .001), while OCPP incidence remained stable (P = .41). Compared with the patients with ICPP, the patients with OCPP were younger (P = .006), were shorter (P = .003), and had higher basal serum testosterone levels (P = .038). Combining 2 to 4 of these readily available clinical cues resulted in good to excellent (all, area under the curve 0.84-0.97, P < .001) overall performance, differentiating organic etiology from idiopathic.

CONCLUSIONS

The estimated incidence of CPP in boys was 0.34 per 10 000, with 26% of cases associated with intracranial pathology. The increase in CPP incidence was driven by rising ICPP rates. Patients with OCPP were characterized by shorter stature, younger age, and higher basal testosterone levels, providing valuable cues for differentiation in addition to brain MRI. Utilizing multiple cues could guide diagnostic decision-making.

Letrozole combined with rhGH treatment increases the adult height of short pubertal boys

OBJECTIVES

This study was performed to investigate the effectiveness of the combination of letrozole and recombinant human growth hormone (rhGH) to improve the predicted adult height (PAH) and final adult height (FAH) of Chinese short pubertal boys.

METHODS

In total, 171 Chinese short pubertal boys were recruited for this study. 96 of them received letrozole (2.5 mg/d) combined with rhGH (33.3-66.6 μg/kg.d), and the others received rhGH alone. Follow-up visits were conducted at 1, 3, 6, 9, and 12 months or regularly after the first treatment. During each visit, plasma samples were collected for clinical tests and biomedical analyses, all of which were performed according to standard protocols. This study was registered at www.chictr.org.cn under ID number ChiCTR1900026142.

RESULTS

After receiving treatment for at least 3 months, 68 boys (91 %) in the rhGH therapy group and 90 (94 %) in the letrozole combined with rhGH (letrozole+rhGH) therapy group achieved an increase in PAH, with the latter treatment leading to a more effective slowing of bone age (BA) advancement. Moreover, the increased PAH showed a significant positive correlation with treatment time in both groups, and letrozole+rhGH increased the PAH to a greater degree than rhGH alone (p=0.0023). And letrozole+rhGH not only slowed the increase in BA more efficiently than rhGH therapy alone (p=0.0025), but also achieved a higher FAH (p=0.0078).

CONCLUSIONS

Letrozole combined with rhGH treatment is a promising therapy to increase the PAH and FAH of Chinese short pubertal boys.

Evaluation of height prediction models: from traditional methods to artificial intelligence

BACKGROUND

Traditional methods for predicting adult height (AHP) rely on manual readings of bone age (BA). However, the incorporation of artificial intelligence has recently improved the accuracy of BA readings and their incorporation into AHP models.

METHODS

This study aimed to identify the AHP model that fits the current average height for adults in Mexico. Using a cross-sectional design, the study included 1173 participants (5-18 yr). BA readings were done by two experts (manually) and with an automated method (BoneXpert®). AHP was carried out using both traditional and automated methods. The best AHP model was the one that was closest to the population mean.

RESULTS

All models overestimated the population mean (males: 0.7-6.7 cm, females: 0.9-3.7 cm). The AHP models with the smallest difference were BoneXpert for males and Bayley & Pinneau for females. However, the manual readings of BA showed significant interobserver variability (up to 43% of predictions between observers exceeded 5 cm using the Bayley & Pinneau method).

CONCLUSION

Traditional AHP models relying on manual BA readings have high interobserver variability. Therefore, BoneXpert is the most reliable option, reducing such variability and providing AHP models that remain close to the mean population height.

IMPACT

Traditional models for predicting adult height often result in overestimated height predictions. The manual reading of bone age is prone to interobserver variability, which can introduce significant biases in the prediction of adult height. The BoneXpert method minimizes the variability associated with traditional methods and demonstrates consistent results in relation to the average height of the population. This study is the first to assess adult height prediction models specifically in the current generations of Mexican children.

Adult height prediction using the growth curve comparison method

Understanding the growth pattern is important in view of child and adolescent development. Due to different tempo of growth and timing of adolescent growth spurt, individuals reach their adult height at different ages. Accurate models to assess the growth involve intrusive radiological methods whereas the predictive models based solely on height data are typically limited to percentiles and therefore rather inaccurate, especially during the onset of puberty. There is a need for more accurate non-invasive methods for height prediction that are easily applicable in the fields of sports and physical education, as well as in endocrinology. We developed a novel method, called Growth Curve Comparison (GCC), for height prediction, based on a large cohort of > 16,000 Slovenian schoolchildren followed yearly from ages 8 to 18. We compared the GCC method to the percentile method, linear regressor, decision tree regressor, and extreme gradient boosting. The GCC method outperformed the predictions of other methods over the entire age span both in boys and girls. The method was incorporated into a publicly available web application. We anticipate our method to be applicable also to other models predicting developmental outcomes of children and adolescents, such as for comparison of any developmental curves of anthropometric as well as fitness data. It can serve as a useful tool for assessment, planning, implementation, and monitoring of somatic and motor development of children and youth.

Timing of Puberty, Pubertal Growth, and Adult Height in Short Children Born Small for Gestational Age Treated With Growth Hormone

CONTEXT

Growth hormone (GH) is used to treat short children born small for gestational age (SGA); however, the effects of treatment on pubertal timing and adult height are rarely studied.

OBJECTIVE

To evaluate adult height and peak height velocity in short GH-treated SGA children.

METHODS

Prospective longitudinal multicenter study. Participants were short children born SGA treated with GH therapy (n = 102). Adult height was reported in 47 children. A reference cohort of Danish children was used. Main outcome measures were adult height, peak height velocity, age at peak height, and pubertal onset. Pubertal onset was converted to SD score (SDS) using Danish reference data.

RESULTS

Gain in height SDS from start of treatment until adult height was significant in both girls (0.94 [0.75; 1.53] SDS, P = .02) and boys (1.57 [1.13; 2.15] SDS, P < .001). No difference in adult height between GH dosage groups was observed. Peak height velocity was lower than a reference cohort for girls (6.5 [5.9; 7.6] cm/year vs 7.9 [7.4; 8.5] cm/year, P < .001) and boys (9.5 [8.4; 10.7] cm/year vs 10.1 [9.7; 10.7] cm/year, P = .002), but no difference in age at peak height velocity was seen. Puberty onset was earlier in SGA boys than a reference cohort (1.06 [-0.03; 1.96] SDS vs 0 SDS, P = .002) but not in girls (0.38 [-0.19; 1.05] SDS vs 0 SDS, P = .18).

CONCLUSION

GH treatment improved adult height. Peak height velocity was reduced, but age at peak height velocity did not differ compared with the reference cohort. SGA boys had an earlier pubertal onset compared with the reference cohort.

Near-Adult Heights and Adult Height Predictions Using Automated and Conventional Greulich-Pyle Bone Age Determinations in Children with Chronic Endocrine Diseases

OBJECTIVES

To validate adult height predictions (BX) using automated and Greulich-Pyle bone age determinations in children with chronic endocrine diseases.

METHODS

Heights and near-adult heights were measured in 82 patients (48 females) with chronic endocrinopathies at the age of 10.45 ± 2.12 y and at time of transition to adult care (17.98 ± 3.02 y). Further, bone age (BA) was assessed using the conventional Greulich-Pyle (GP) method by three experts, and by BoneXpert™. PAH were calculated using conventional BP tables and BoneXpert™.

RESULTS

The conventional and the automated BA determinations revealed a mean difference of 0.25 ± 0.72 y (p = 0.0027). The automated PAH by BoneXpert™ were 156.26 ± 0.86 cm (SDS - 2.01 ± 1.07) in females and 171.75 ± 1.6 cm (SDS - 1.29 ± 1.06) in males, compared to 153.95 ± 1.12 cm (SDS - 2.56 ± 1.5) in females and 169.31 ± 1.6 cm (SDS - 1.66 ± 1.56) in males by conventional BP, respectively and in comparison to near-adult heights 156.38 ± 5.84 cm (SDS - 1.91 ± 1.15) in females and 168.94 ± 8.18 cm (SDS - 1.72 ± 1.22) in males, respectively.

CONCLUSION

BA ratings and adult height predictions by BoneXpert™ in children with chronic endocrinopathies abolish rater-dependent variability and enhance reproducibility of estimates thereby refining care in growth disorders. Conventional methods may outperform automated analyses in specific cases.

Study of Multidimensional and High-Precision Height Model of Youth Based on Multilayer Perceptron

Predicting the adult height of children accurately has great social value for the selection of outstanding athlete as well as early detection of children's growth disorders. Currently, the mainstream method used to predict adult height in China has three problems: its standards are not uniform; it is stale for current Chinese children; its accuracy is not satisfactory. This article uses the data collected by the Chinese Children and Adolescents' Physical Fitness and Growth Health Project in Zhejiang primary and secondary schools. We put forward a new multidimensional and high-precision youth growth curve prediction model, which is based on multilayer perceptron. First, this model uses multidimensional growth data of children as predictors and then utilizes multilayer perceptron to predict the children's adult height. Second, we find the Table of Height Standard Deviation of Chinese Children and fit the data of zero standard deviation to obtain the curve. This curve is regarded as Chinese children's mean growth curve. Third, we use the least-squares method and the mean curve to calculate the individual growth curve. Finally, the individual curve can be used to predict children's state height. Experimental results show that this adult height prediction model's accuracy (between 2 cm) of boys and girls reached 90.20% and 88.89% and the state height prediction accuracy reached 77.46% and 74.93%. Compared with Bayley–Pinneau, the adult height prediction is improved 19.61% for boys and 13.33% for girls. Compared with BoneXpert, the adult height prediction is improved 25.49% for boys and 6.67% for girls. Compared with the method based on the bone age growth map, the adult height prediction is improved 15.69% for boys and 24.45% for girls.

A Novel Method for Adult Height Prediction in Children with Idiopathic Short Stature Derived from a German-Dutch Cohort

Context

Prediction of adult height (AH) is important in clinical management of short children. The conventional methods of Bayley-Pinneau (BP) or Roche-Wainer-Thissen (RWT) have limitations.

Objective

We aimed to develop a set of algorithms for AH prediction in patients with idiopathic short stature (ISS) which are specific for combinations of predicting variables.

Methods

Demographic and auxologic data were collected in childhood (1980s) and at AH (1990s). Data were collected by Dutch and German referral centers for pediatric endocrinology. A total of 292 subjects with ISS (219 male, 73 female) were enrolled. The population was randomly split into modeling (n = 235) and validation (n = 57) cohorts. Linear multi-regression analysis was performed with predicted AH (PAH) as response variable and combinations of chronological age (CA), baseline height, parental heights, relative bone age (BA/CA), birth weight, and sex as exploratory variables.

Results

Ten models including different exploratory variables were selected with adjusted R² ranging from 0.84 to 0.78 and prediction errors from 3.16 to 3.68 cm. Applied to the validation cohort, mean residuals (PAH minus observed AH) ranged from −0.29 to −0.82 cm, while the conventional methods showed some overprediction (BP: +0.53 cm; RWT: +1.33 cm; projected AH: +3.81 cm). There was no significant trend of residuals with PAH or any exploratory variables, in contrast to BP and projected AH.

Conclusion

This set of 10 multi-regression algorithms, developed specifically for children with ISS, provides a flexible tool for AH prediction with better accuracy than the conventional methods.

Growth Hormone/Insulin-Like Growth Factor 1 Axis Associated with Modifiers Factors in Children with Sickle Cell Anemia

BACKGROUND

Sickle cell anemia is a disease that develops episodes of acute pain and multiple organ dysfunction that can affect the growth hormone/insulin-like growth factor 1 (GH/IGF-1) axis. The severity of sickle cell anemia is influenced by modifying factors, such as levels of fetal hemoglobin (HbF), the co-inheritance of alpha-thalassemia, or treatment with hydroxyurea.

METHODS

This cross-sectional study in children with sickle cell anemia evaluated bone age (BA), adult height prediction (AHP) using BA, a target height (TH) calculated as the mean SDS of the parents, and laboratory parameters. Children were grouped according to serum levels of HbF, co-inheritance of alpha-thalassemia, and hydroxyurea therapy.

RESULTS

The mean age of the 39 children was 8.2±2.2 years old. The average height was -0.75±0.30 SDS, and 10.3% (4/39) had short stature. Adjusted levels of IGF-1 or IGFBP-3 were significantly higher in children with sickle cell anemia on hydroxyurea treatment, in children with HbF levels >10%, and in those without alpha-thalassemia. Using SDS, the growth potential of children with sickle cell anemia in relation to their parents, calculated by the difference between AHP and TH, as well as the difference between children's height and their TH, were lower in children with co-inheritance of alpha-thalassemia Conclusion: The study showed an association between modifying factors and the GH/IGF-1 axis in children with sickle cell anemia. Additionally, the co-inheritance of alpha-thalassemia was associated with decreased height in these children when adjusted for their parents' height.

Traditional and New Methods of Bone Age Assessment-An Overview

Bone age is one of biological indicators of maturity used in clinical practice and it is a very important parameter of a child’s assessment, especially in paediatric endocrinology. The most widely used method of bone age assessment is by performing a hand and wrist radiograph and its analysis with Greulich-Pyle or Tanner-Whitehouse atlases, although it has been about 60 years since they were published. Due to the progress in the area of Computer-Aided Diagnosis and application of artificial intelligence in medicine, lately, numerous programs for automatic bone age assessment have been created. Most of them have been verified in clinical studies in comparison to traditional methods, showing good precision while eliminating inter- and intra-rater variability and significantly reducing the time of assessment. Additionally, there are available methods for assessment of bone age which avoid X-ray exposure, using modalities such as ultrasound or magnetic resonance imaging.

Creation and Validation of a Shorthand Magnetic Resonance Imaging Bone Age Assessment Tool of the Knee as an Alternative Skeletal Maturity Assessment

BACKGROUND

In managing pediatric knee conditions, an accurate bone age assessment is often critical for diagnostic, prognostic, and treatment purposes. Historically, the Greulich and Pyle atlas (hand atlas) has been the gold standard bone age assessment tool. In 2013, a shorthand bone age assessment tool based on this atlas (hand shorthand) was devised as a simpler and more efficient alternative. Recently, a knee magnetic resonance imaging (MRI) bone age atlas (MRI atlas) was created to circumvent the need for a left-hand radiograph.

PURPOSE

To create a shorthand version of the knee MRI atlas.

STUDY DESIGN

Cohort study (diagnosis); Level of evidence, 2.

METHODS

A shorthand bone age assessment method was created utilizing the previously published MRI atlas, which utilizes several criteria that are visualized across a series of images. The MRI shorthand draws on characteristic criteria for each age that are best observed on a single MRI scan. For validation, we performed a retrospective assessment of skeletally immature patients. One reader performed the bone age assessment using the MRI atlas and the MRI shorthand on 200 patients. Then, 4 readers performed the bone age assessment with the hand atlas, hand shorthand, MRI atlas, and MRI shorthand on a subset of 22 patients in a blinded fashion. All 22 patients had a knee MRI scan and a left-hand radiograph within 4 weeks of each other. Interobserver and intraobserver reliability, as well as variability among observers, were evaluated.

RESULTS

A total of 200 patients with a mean age of 13.5 years (range, 9.08-17.98 years) were included in this study. Also, 22 patients with a mean age of 13.3 years (range, 9.0-15.6 years) had a knee MRI scan and a left-hand radiograph within 4 weeks. The intraobserver and interobserver reliability of all 4 assessment tools were acceptable (intraclass correlation coefficient [ICC] ≥ 0.8; P < .001). When comparing the MRI shorthand with the MRI atlas, there was excellent agreement (ICC = 0.989), whereas the hand shorthand compared with the hand atlas had good agreement (ICC = 0.765). The MRI shorthand also had perfect agreement in 50% of readings among all 4 readers, and 95% of readings had agreement within 1 year, whereas the hand shorthand had perfect agreement in 32% of readings and 77% agreement within 1 year.

CONCLUSION

The MRI shorthand is a simple and efficient means of assessing the skeletal maturity of adolescent patients with a knee MRI scan. This bone age assessment technique had interobserver and intraobserver reliability equivalent to or better than the standard method of utilizing a left-hand radiograph.

Important Tools for Use by Pediatric Endocrinologists in the Assessment of Short Stature

Assessment and management of children with growth failure has improved greatly over recent years. However, there remains a strong potential for further improvements by using novel digital techniques. A panel of experts discussed developments in digitalization of a number of important tools used by pediatric endocrinologists at the third 360° European Meeting on Growth and Endocrine Disorders, funded by Merck KGaA, Germany, and this review is based on those discussions. It was reported that electronic monitoring and new algorithms have been devised that are providing more sensitive referral for short stature. In addition, computer programs have improved ways in which diagnoses are coded for use by various groups including healthcare providers and government health systems. Innovative cranial imaging techniques have been devised that are considered safer than using gadolinium contrast agents and are also more sensitive and accurate. Deep-learning neural networks are changing the way that bone age and bone health are assessed, which are more objective than standard methodologies. Models for prediction of growth response to growth hormone (GH) treatment are being improved by applying novel artificial intelligence methods that can identify non-linear and linear factors that relate to response, providing more accurate predictions. Determination and interpretation of insulin-like growth factor-1 (IGF-1) levels are becoming more standardized and consistent, for evaluation across different patient groups, and computer-learning models indicate that baseline IGF-1 standard deviation score is among the most important indicators of GH therapy response. While physicians involved in child growth and treatment of disorders resulting in growth failure need to be aware of, and keep abreast of, these latest developments, treatment decisions and management should continue to be based on clinical decisions. New digital technologies and advancements in the field should be aimed at improving clinical decisions, making greater standardization of assessment and facilitating patient-centered approaches.

Cortical Bone Mass is Low in Boys with Klinefelter Syndrome and Improves with Oxandrolone

Context

Klinefelter syndrome (KS) is the most common sex aneuploidy in men. Affected males have hypogonadism, and, as a result, face an increased risk for osteoporosis and fractures. Androgen therapy is standard in adolescents and adults with KS but has not been used earlier in childhood.

Objective

To determine the effects of androgen treatment on bone mass in children with KS.

Methods

Randomized, double-blind, placebo-controlled clinical trial of oxandrolone (OX; 0.06 mg/kg daily; n = 38) versus placebo (PL; n = 40) for 2 years in boys with KS (ages 4-12 years). Changes in bone mass were examined by digital x-ray radiogrammetry, which determines the Bone Health Index (BHI) and standard deviation score (SDS).

Results

BHI SDS was similar between groups at baseline (–0.46 ± 1.1 vs –0.34 ± 1.0 OX vs PL, P > .05) and higher in the OX group at 2 years (–0.1 ± 1.3 vs –0.53 ± 0.9, OX vs PL, P < .01). At baseline, BHI SDS values of all subjects were not normally distributed with 25.7% of subjects plotted below –1 SDS (P < .001), suggesting a deficit in bone mass. In total, 13.5% of subjects had sustained a fracture and their BHI SDS was lower than those with no fractures (–1.6 ± 1.3 vs –0.3 ± 1.0, P = .004).

Conclusion

Bone mass using BHI SDS is reduced in some children with KS and improves with OX. Since these individuals are at risk for osteoporosis, age-appropriate androgen replacement and future studies on bone health in children with KS should be further explored.

The Importance of Childhood for Adult Health and Development-Study Protocol of the Zurich Longitudinal Studies

Evidence is accumulating that individual and environmental factors in childhood and adolescence should be considered when investigating adult health and aging-related processes. The data required for this is gathered by comprehensive long-term longitudinal studies. This article describes the protocol of the Zurich Longitudinal Studies (ZLS), a set of three comprehensive cohort studies on child growth, health, and development that are currently expanding into adulthood. Between 1954 and 1961, 445 healthy infants were enrolled in the first ZLS cohort. Their physical, motor, cognitive, and social development and their environment were assessed comprehensively across childhood, adolescence, and into young adulthood. In the 1970s, two further cohorts were added to the ZLS and assessed with largely matched study protocols: Between 1974 and 1979, the second ZLS cohort included 265 infants (103 term-born and 162 preterm infants), and between 1970 and 2002, the third ZLS cohort included 327 children of participants of the first ZLS cohort. Since 2019, the participants of the three ZLS cohorts have been traced and invited to participate in a first wave of assessments in adulthood to investigate their current health and development. This article describes the ZLS study protocol and discusses opportunities, methodological and conceptual challenges, and limitations arising from a long-term longitudinal cohort recruited from a study about development in early life. In the future, the ZLS will provide data to investigate childhood antecedents of adult health outcomes and, ultimately, will help respond to the frequent call of scientists to shift the focus of aging research into the first decades of life and, thus, to take a lifespan perspective on aging.

Skeletal Maturation in the Current Pediatric Mexican Population

OBJECTIVE

The most commonly used methods for bone age (BA) reading were described in the Caucasian population decades ago. However, there are secular trends in skeletal maturation and different BA patterns between ethnic groups. Automated BA reading makes updating references easier and more precise than human reading. The objective of the present study was to present automated BA reference curves according to chronological age and gender in the Mexican population and compare the maturation tempo with that of other populations.

METHODS

The study included 923 healthy participants aged 5 to 18 years between 2017 and 2018. A hand radio-graph was analyzed using BoneXpert software to obtain the automated BA reading according to Greulich and Pyle (G&P) and Tanner-Whitehouse 2 (TW2) references. We constructed reference curves using the average difference between the BA and chronological age according to sex and age.

RESULTS

The G&P and TW2 automated reference curves showed that Mexican boys exhibit delays in BA during middle childhood by 0.5 to 0.7 (95% confidence interval &lsqb;CI], -0.9 to -0.2) years; however, they demonstrate an advanced BA of up to 1.1 (95% CI, 0.8 to 1.4) years at the end of puberty. Mexican girls exhibited a delay in BA by 0.3 to 0.6 (95% CI, -0.9 to -0.1) years before puberty and an advanced BA of up to 0.9 (95% CI, 0.7 to 1.2) years at the end of puberty.

CONCLUSION

Mexican children aged <10 years exhibited a delay in skeletal maturity, followed by an advanced BA by approximately 1 year at the end of puberty. This may affect the estimation of growth potential in this population.

Biological Maturity Status in Elite Youth Soccer Players: A Comparison of Pragmatic Diagnostics With Magnetic Resonance Imaging

The influence of biological maturity status (BMS) on talent identification and development within elite youth soccer is critically debated. During adolescence, maturity-related performance differences within the same age group may cause greater chances of being selected for early maturing players. Therefore, coaches need to consider players' BMS. While standard methods for assessing BMS in adolescents are expensive and time-consuming imaging techniques (i.e., X-ray and MRI), there also exist more pragmatic procedures. This study aimed to evaluate commonly used methods to assess BMS within a highly selected sample of youth soccer players. A total of N = 63 elite male soccer players (U12 and U14) within the German Soccer Association's talent promotion program completed a test battery assessing BMS outcomes. Utilizing MRI diagnostics, players' skeletal age (SA_MRI) was determined by radiologists and served as the reference method. Further commonly used methods included skeletal age measured by an ultrasound device (SA_US), the maturity offset (MO_MIR), and the percentage of adult height (PAH_KR). The relation of these alternative BMS outcomes to SA_MRI was examined using different perspectives: performing bivariate correlation analyses (1), modeling BMS as a latent variable (BMS_lat) based on the multiple alternative diagnostics (2), and investigating individual differences in agreement (3). (1) Correlations of SA_MRI and the further BMS variables ranked from r = 0.80 to r = 0.84 for the total sample and were lower for U12 (0.56 ≤ r ≤ 0.66), and U14 (0.61 ≤ r ≤ 0.74) (2). The latent structural equation modeling (SEM) (R² = 51%) revealed a significant influence on BMS_lat for MO_MIR (β = 0.51, p <0.05). The additional contribution of PAH_KR (β = 0.27, p = 0.06) and SA_US (β = −0.03, p = 0.90) was rather small (3). The investigation of individual differences between the reference method and alternative diagnostics indicated a significant bias for MO_MIR (p <0.01). The results support the use of economical and time-efficient methods for assessing BMS within elite youth soccer. Bivariate correlation analyses as well as the multivariate latent variable approach highlight the measures' usefulness. However, the observed individual level differences for some of the utilized procedures led to the recommendation for practitioners to use at least two alternative assessment methods in order to receive more reliable information about players' BMS within the talent promotion process.

Modernization of bone age assessment: comparing the accuracy and reliability of an artificial intelligence algorithm and shorthand bone age to Greulich and Pyle

Greulich and Pyle (GP) is one of the most common methods to determine bone age from hand radiographs. In recent years, new methods were developed to increase the efficiency in bone age analysis like the shorthand bone age (SBA) and automated artificial intelligence algorithms.

OBJECTIVE

The aim of this study is to evaluate the accuracy and reliability of these two methods and examine if the reduction in analysis time compromises their efficacy.

METHODS

Two hundred thirteen males and 213 females had their bone age determined by two separate raters using the SBA and GP methods. Three weeks later, the two raters repeated the analysis of the radiographs. The raters timed themselves using an online stopwatch. De-identified radiographs were securely uploaded to an automated algorithm developed by a group of radiologists in Toronto. The gold standard was determined to be the radiology report attached to each radiograph, written by experienced radiologists using GP.

RESULTS

Intraclass correlation between each method and the gold standard fell within the range of 0.8-0.9, highlighting significant agreement. Most of the comparisons showed a statistically significant difference between the new methods and the gold standard; however, it may not be clinically significant as it ranges between 0.25 and 0.5 years. A bone age is considered clinically abnormal if it falls outside 2 standard deviations of the chronological age; standard deviations are calculated and provided in GP atlas.

CONCLUSION

The shorthand bone age method and the automated algorithm produced values that are in agreement with the gold standard while reducing analysis time.

A multi-scale data fusion framework for bone age assessment with convolutional neural networks

Bone age assessment (BAA) has various clinical applications such as diagnosis of endocrine disorders and prediction of final adult height for adolescents. Recent studies indicate that deep learning techniques have great potential in developing automated BAA methods with significant advantages over the conventional methods based on handcrafted features. In this paper, we propose a multi-scale data fusion framework for bone age assessment with X-ray images based on non-subsampled contourlet transform (NSCT) and convolutional neural networks (CNNs). Unlike the existing CNN-based BAA methods that adopt the original spatial domain image as network input directly, we pre-extract a rich set of features for the input image by performing NSCT to obtain its multi-scale and multi-direction representations. This feature pre-extraction strategy could be beneficial to network training as the number of annotated examples in the problem of BAA is typically quite limited. The obtained NSCT coefficient maps at each scale are fed into a convolutional network individually and the information from different scales are then merged to achieve the final prediction. Specifically, two CNN models with different data fusion strategies are presented for BAA: a regression model with feature-level fusion and a classification model with decision-level fusion. Experiments on the public BAA dataset Digital Hand Atlas demonstrate that the proposed method can obtain promising results and outperform many state-of-the-art BAA methods. In particular, the proposed approaches exhibit obvious advantages over the corresponding spatial domain approaches (generally with an improvement of more than 0.1 years on the mean absolute error), showing great potential in the future study of this field.

Skeletal maturation and predicted adult height in adolescents with temporomandibular joint osteoarthritis

BACKGROUND

The occurrence of osteoarthritis (OA) of the temporomandibular joint (TMJ) in juveniles could be associated with fluctuating levels of oestrogen and growth hormone (GH) during adolescence.

OBJECTIVE

To investigate extent of skeletal maturation and predicted adult height in adolescents with TMJ OA.

METHOD

In total, 155 adolescents (54 males, 101 females; mean age, 14.1 ± 2.0 years) were enrolled. Among them, 19 adolescents (CON) showed no sign of TMD, 50 adolescents exhibited signs of disc displacement but did not have TMJ OA (TMDnoOA), 23 adolescents exhibited the initial stage of TMJ OA (TMJOAini) and 63 adolescents exhibited the severe stage of TMJ OA (TMJOApro). TMJ OA was diagnosed based on the Research Diagnostic Criteria axis I and bone age was estimated using the Greulich-Pyle method. The height, weight and body mass index of participated adolescents were measured and statistically converted to z-scores. The predicted adult height and age of peak height velocity (APHV) were calculated using the BoneXpert® software.

RESULTS

In female adolescents, the differences between the chronological and bone ages were significantly higher and the z-score for height was significantly lower in the TMJOApro. Female adolescents with TMJOA exhibited a significantly shorter predicted adult height and earlier APHV than those in the CON and TMDnoOA.

CONCLUSION

The adolescents with TMJ OA exhibited premature skeletal maturations and short predicted adult stature, particularly the female adolescents.

Letrozole versus testosterone for promotion of endogenous puberty in boys with constitutional delay of growth and puberty: a randomised controlled phase 3 trial

BACKGROUND

The treatment of constitutional delay of growth and puberty (CDGP) is an underinvestigated area in adolescent medicine. We tested the hypothesis that peroral aromatase inhibition with letrozole is more efficacious than intramuscular injection of low-dose testosterone in inducing puberty in boys with CDGP.

METHODS

We did a randomised, controlled, open-label trial at four paediatric centres in Finland. Boys aged at least 14 years with CDGP who wanted medical intervention and exhibited the first signs of puberty were randomly assigned in blocks of ten to receive either six intramuscular injections of low-dose testosterone (about 1 mg/kg bodyweight) every 4 weeks for 6 months or peroral letrozole 2·5 mg once daily for 6 months. All boys were followed up for 6 months after the end of treatment. The primary outcomes were changes in testicular volume and hormonal markers of puberty at 6 months after treatment initiation, which were assessed in all participants who received the assigned treatment. All patients were included in the safety analysis. This study is registered with ClinicalTrials.gov, number NCT01797718.

FINDINGS

Between Aug 1, 2013, and Jan 30, 2017, 30 boys were randomly assigned to receive testosterone (n=15) or letrozole (n=15). One boy in the testosterone group was excluded from the primary analyses because of a protocol deviation. During treatment, boys in the letrozole group had higher serum concentrations of luteinising hormone, follicle-stimulating hormone, testosterone, and inhibin B than did boys in the testosterone group. Testicular growth from baseline to 6 months was greater in the letrozole group than in the testosterone group (7·2 mL [95% CI 5·2-9·3] vs 2·2 mL [1·4-2·9]; between-group difference per month 0·9 mL [95% CI 0·6-1·2], p<0·0001). Most adverse events were mild. One boy in the testosterone group had aggressive behaviour for 1 week after each injection, and one boy in the letrozole group had increased irritability at 6 months.

INTERPRETATION

Letrozole might be a feasible alternative treatment to low-dose testosterone for boys with CDGP who opt for medical intervention. However, the risks and benefits of manipulating the reproductive axis during early puberty should be weighed carefully.

FUNDING

Helsinki University Hospital, Academy of Finland, and Finnish Foundation for Pediatric Research.

Near final height in Korean children referred for evaluation of short stature: clinical utility and analytical validity of height prediction methods

PURPOSE

Predicted adult height (PAH) is often crucial to decision-making about treatment with human growth hormone (GH) or gonadotropin-releasing hormone agonist in children with short stature. This study compares final adult height (FAH) with different methods used to determine PAH and assesses the clinical utility and analytical validity of height prediction for children not treated with GH.

METHODS

Clinical findings were retrospectively analyzed, and the heights of 44 children (22 males and 22 females) who visited our clinic between August 2006 and June 2017 and reached near final adult height (NFAH) were evaluated. Children treated with GH were excluded. We compared measured NFAH to PAH using the Bayley-Pinneau (BP), Tanner-Whitehouse Mark 2, and Roche-Wainer-Thissen (RWT) methods.

RESULTS

Pearson correlation between all 3 prediction methods and NFAH showed high positive correlations in males and females (P<0.05). The average difference between PAH and NFAH for the BP method (0.4±3.9 cm) was significantly lower than those for the RWT and TW 2 methods in females (P=0.000, analysis of variance). Furthermore, only PAH by the BP method in females was very close to measured NFAH (paired t-test). A Bland-Altman plot verified that 95% of the differences between the PAH and NFAH exist between limits of agreement (mean±1.96 standard deviation).

CONCLUSIONS

The BP method is more useful to predict NFAH in females than other methods. Careful attention is still required when using such tools because PAH can be inaccurate. Therefore, a more accurate FAH prediction model for Korean children is needed.

Bone Age: A Handy Tool for Pediatric Providers

Pediatricians have relied on methods for determining skeletal maturation for >75 years. Bone age continues to be a valuable tool in assessing children's health. New technology for bone age determination includes computer-automated readings and assessments obtained from alternative imaging modalities. In addition, new nonclinical bone age applications are evolving, particularly pertaining to immigration and children's rights to asylum. Given the significant implications when bone ages are used in high-stake decisions, it is necessary to recognize recently described limitations in predicting accurate age in various ethnicities and diseases. Current methods of assessing skeletal maturation are derived from primarily white populations. In modern studies, researchers have explored the accuracy of bone age across various ethnicities in the United States. Researchers suggest there is evidence that indicates the bone ages obtained from current methods are less generalizable to children of other ethnicities, particularly children with African and certain Asian backgrounds. Many of the contemporary methods of bone age determination may be calibrated to individual populations and hold promise to perform better in a wider range of ethnicities, but more data are needed.

Short stature homeobox-containing gene duplications in 3.7% of girls with tall stature and normal karyotypes

AIM

The short stature homeobox-containing gene (SHOX) plays an important role in short stature, but has not been explored in detail in a tall stature population before. This study explored the prevalence of SHOX aberrations in girls diagnosed with idiopathic tall stature with a normal karyotype.

METHODS

We studied SHOX aberrations in 81 girls with a median age of 10.43 (7.17-12.73) years diagnosed with tall stature who were referred to our clinic at Copenhagen University Hospital, Denmark, between 2003 and 2013. SHOX copy variations were analysed by quantitative polymerase chain reaction, and aberrations were confirmed by multiplex ligation probe-dependent amplification.

RESULTS

One extra SHOX copy was found in three (3.7%) of the 81 girls with tall stature, and their heights were 2.87, 3.71 and 3.98 standard deviation scores (SDS) and above the median height SDS of the girls with two SHOX copies. Their sitting height/height ratios (-3.08, -2.00 and -2.18 SDS) were all lower than the population mean. Despite these SHOX duplications, the three girls were clinically and biochemically comparable to the 78 girls with two SHOX copies.

CONCLUSION

This study was the first to demonstrate SHOX duplications in three girls with tall stature and normal karyotypes.

Testosterone Therapy Improves the First Year Height Velocity in Adolescent Boys with Constitutional Delay of Growth and Puberty

BACKGROUND

Constitutional delay of growth and puberty (CDGP) can cause significant psychological distress in adolescent boys. Although testosterone usage in this group has not been shown to affect the final adult height, the effect on the first year height velocity has not been widely reported.

OBJECTIVES

The aim is to determine whether testosterone treatment improves the first year height velocity in boys with CDGP when compared to boys with CDGP who go through puberty spontaneously.

METHODS

Retrospective data from 23 adolescent boys with CDGP was analysed. Ten out of 23 boys (43%) received testosterone injection (testosterone enanthate, 125 mg), once every 6 weeks for 3 doses in total. Both the groups (treated and untreated) had their height, bone age and testicular volume measured at the baseline, The height velocity and final predicted adult height were compared at the end of one year between both the groups.

RESULTS

In the testosterone-untreated group, the mean (± SD) chronological age, bone age, height standard deviation scores (SDS) and testicular volume were 14.3 years (± 0.3),12.1 years (± 1.6), -1.9 (± 0.8) and 4.7 mL (± 1.1) respectively. Within the testosterone-treated group the mean (± SD) chronological age, bone age, height SDS and testicular volume at presentation were 14.4 years (± 0.4), 11 years (± 1.6), -2.1 SD(± 0.6) and 4.5 mL (± 1.2) respectively. The mean age of treatment with testosterone was 14.4 years (± 0.44). The mean height velocity one year after treatment was 8.4 cm/year (± 1.7) in the testosterone treated group when compared to 6.1 cm/year (± 2.1) in the patients who did not receive treatment (P = 0.01). There was no significant difference in the final predicted height between the 2 groups (P = 0.15).

CONCLUSIONS

Testosterone therapy improves the first year height velocity in boys with CDGP, without influencing their final predicted height.

Metacarpal bone loss in patients with rheumatoid arthritis estimated by a new Digital X-ray Radiogrammetry method - initial results

BACKGROUND

The Digital X-ray Radiogrammetry (DXR) method measures the cortical bone thickness in the shafts of the metacarpals and has demonstrated its relevance in the assessment of hand bone loss caused by rheumatoid arthritis (RA). The aim of this study was to validate a novel approach of the DXR method in comparison with the original version considering patients with RA.

METHOD

The study includes 49 patients with verified RA. The new version is an extension of the BoneXpert method commonly used in pediatrics which has these characteristics: (1) It introduces a new technique to analyze the images which automatically validates the results for most images, and (2) it defines the measurement region relative to the ends of the metacarpals. The BoneXpert method measures the Metacarpal Index (MCI) at the metacarpal bone (II to IV). Additionally, the MCI is quantified by the DXR X-posure System.

RESULTS

The new version correctly analyzed all 49 images, and 45 were automatically validated. The standard deviation between the MCI results of the two versions was 2.9% of the mean MCI. The average Larsen score was 2.6 with a standard deviation of 1.3. The correlation of MCI to Larsen score was -0.81 in both versions, and there was no significant difference in their ability to detect erosions.

CONCLUSION

The new DXR version (BoneXpert) validated 92% of the cases automatically, while the same good correlation to RA severity could be presented compared to the old version.

Evaluation and phenotypic characteristics of 293 Danish girls with tall stature: effects of oral administration of natural 17β-estradiol

BACKGROUND

Reduction of adult height by sex steroid treatment was introduced decades ago in tall statured children, but controlled trials are lacking and treatment is controversial. In this study, we wanted to evaluate the phenotypic characteristics in girls referred due to tall stature and the effect of oral administration of 17β-estradiol on predicted adult height in girls.

METHODS

A single-centre retrospective observational study of 304 girls evaluated consecutively due to tall stature between 1993 and 2013. 207 patients diagnosed with constitutionally tall stature (CTS), 60 (29%) girls ended up being treated with 17β-estradiol with a duration of 1.7 y (1.2; 2.5) (median (25; 75 percentile)), and final height was available in 26 girls.

RESULTS

At baseline, 20% of girls with CTS had supranormal IGF-I, whereas reproductive hormones were within the normal range. Final adult height was reduced with 1.6 ± 2.1 cm in the girls treated with 17β-estradiol when compared to initial prediction. Chronological age, bone age, estradiol, and IGF-I at baseline or estrogen dose did not predict height reduction.

CONCLUSIONS

Serum IGF-I was elevated tall statured children, but did not predict the effect of treatment with 17β-estradiol, which caused a modest reduction in final adult height.

Psoriatic arthritis is associated with bone loss of the metacarpals

Background

BoneXpert (BX) is a newly developed medical device based on digital X-ray radiogrammetry to measure human cortical bone thickness. The aim of this study was to quantify cortical bone loss of the metacarpals in patients with psoriatic arthritis (PsA) and compare these findings with other radiological scoring methods.

Methods

The study includes 104 patients with verified PsA. The BX method was used to measure the Metacarpal Index (MCI) at the metacarpal bones (II–IV). Additionally, the T-score of the MCI (T-score_MCI) was calculated. Radiographic severity was determined by the Psoriatic Arthritis Ratingen Score (Proliferation Score and Destruction Score) as published by Wassenberg et al. and the Psoriatic Arthritis modified van der Heijde Sharp Score (Joint Space Narrowing Score and Erosion Score).

Results

For the total PsA study cohort, the T-score_MCI was significantly reduced by −1.289 ± 1.313 SD. The MCI negatively correlated with the Proliferation Score (r = −0.732; p < 0.001) and the Destruction Score (r = −0.771; p < 0.001) of the Psoriatic Arthritis Ratingen Score. Lower coefficients of correlations were observed for the Psoriatic Arthritis modified van der Heijde Sharp Score. In this context, a severity-dependent and PsA-related periarticular demineralisation as measured by the MCI was quantified. The strongest reduction of −30.8 % (p < 0.01) was observed for the MCI in the Destruction Score.

Conclusions

The BX MCI score showed periarticular demineralisation and severity-dependent bone loss in patients with PsA. The measurements of the BX technique were able to sensitively differentiate between the different stages of disease manifestation affecting bone integrity and thereby seem to achieve the potential to be a surrogate marker of radiographic progression in PsA.

Automated determination of bone age from hand X-rays at the end of puberty and its applicability for age estimation

The BoneXpert method for automated determination of bone age from hand X-rays was introduced in 2009, covering the Greulich-Pyle bone age ranges up to 17 years for boys and 15 years for girls. This paper presents an extension of the method up to bone age 19 years for boys and 18 years for girls. The extension was developed based on images from the First Zurich Longitudinal Study of 231 healthy children born in 1954-1956 and followed with annual X-rays of both hands until adulthood. The method was validated on two cross-sectional studies of healthy children from Rotterdam and Los Angeles. We found root mean square deviations from manual rating of 0.69 and 0.45 years in these two studies for boys in the bone age range 17-19 years. For girls, the deviations were 0.75 and 0.59 years, respectively, in the bone age range 15-18 years. It is shown how the automated bone age method can be applied to infer the age probability distribution for healthy Caucasian European males. Considering a population with age 15.0-21.0 years, the method can be used to decide whether the subject is above 18 years with a false positive rate (children classified as adults) of 10 % (95% confidence interval = 7-13%) and a false negative rate of 30 % (adults classified as children). To apply this method in other ethnicities will require a study of the average of "bone age - age" at the end of puberty, i.e. how much this population is shifted relative to the Greulich-Pyle standard.

Automated Classification of Epiphyses in the Distal Radius and Ulna using a Support Vector Machine

The aim of this study was to automatically classify epiphyses in the distal radius and ulna using a support vector machine (SVM) and to examine the accuracy of the epiphyseal growth grades generated by the support vector machine. X-ray images of distal radii and ulnae were collected from 140 Chinese teenagers aged between 11.0 and 19.0 years. Epiphyseal growth of the two elements was classified into five grades. Features of each element were extracted using a histogram of oriented gradient (HOG), and models were established using support vector classification (SVC). The prediction results and the validity of the models were evaluated with a cross-validation test and independent test for accuracy (PA ). Our findings suggest that this new technique for epiphyseal classification was successful and that an automated technique using an SVM is reliable and feasible, with a relative high accuracy for the models.

Validation of adult height prediction based on automated bone age determination in the Paris Longitudinal Study of healthy children

BACKGROUND

An adult height prediction model based on automated determination of bone age was developed and validated in two studies from Zurich, Switzerland. Varied living conditions and genetic backgrounds might make the model less accurate.

OBJECTIVE

To validate the adult height prediction model on children from another geographical location.

MATERIALS AND METHODS

We included 51 boys and 58 girls from the Paris Longitudinal Study of children born 1953 to 1958. Radiographs were obtained once or twice a year in these children from birth to age 18. Bone age was determined using the BoneXpert method. Radiographs in children with bone age greater than 6 years were considered, in total 1,124 images.

RESULTS

The root mean square deviation between the predicted and the observed adult height was 2.8 cm for boys in the bone age range 6-15 years and 3.1 cm for girls in the bone age range 6-13 years. The bias (the average signed difference) was zero, except for girls below bone age 12, where the predictions were 0.8 cm too low.

CONCLUSION

The accuracy of the BoneXpert method in terms of root mean square error was as predicted by the model, i.e. in line with what was observed in the Zurich studies.

Bone age: assessment methods and clinical applications

The main bone age assessment methods are the Greulich-Pyle and Tanner-Whitehouse 2 methods, both of which involve left hand and wrist radiographs. Several other bone age assessment methods have been developed, including ultrasonographic, computerized, and magnetic resonance (MR) imaging methods. The ultrasonographic method appears unreliable in children with delayed and advanced bone age. MR imaging is noninvasive; however, bone age assessment using MR imaging is relatively new, and further examinations are needed. An automated method for determining bone age, named BoneXpert, has been validated for Caucasian children with growth disorders and children of various ethnic groups. Sex hormones are necessary for bone growth and maturation in children with a bone age corresponding to normal pubertal age, and estrogen is essential for growth plate closure. Bone age is an effective indicator for diagnosing and treating various diseases. A new method for adult height prediction based on bone age has been developed using BoneXpert, in addition to the commonly used Bayley-Pinneau and Tanner-Whitehouse mark II methods. Furthermore, bone age may become a predictor for the timing of peak height velocity and menarche.

Validation of automated Greulich-Pyle bone age determination in children with chronic renal failure?

Growth failure is a common problem in children with chronic kidney disease (CKD). The causes are multifactorial and are associated with increased mortality and morbidity. Standard deviations of bone age versus chronological age in children with CKD have not been developed to date. Accurate and early treatment of bone age is an important component of determining the utility of GH therapy. Improvements in bone age assessments are being evaluated to optimize the understanding of growth delay in CKD.

Advances in pubertal growth and factors influencing it: Can we increase pubertal growth?

Puberty is a period of development characterized by partially concurrent changes which includes growth acceleration, alteration in body composition and appearance of secondary sex characteristics. Puberty is characterized by an acceleration and then deceleration in skeletal growth. The initiation, duration and amount of growth vary considerably during the growth spurt. Pubertal growth and biological maturation are dynamic processes regulated by a variety of genetic and environmental factors. Changes in skeletal maturation and bone mineral accretion concomitant with the stage of pubertal development constitute essential components in the evaluation of growth during this pubertal period. Genetic, endocrine and nutritional factors and ethnicity contribute variably to the amount of growth gained during this important period of rapid changes. Many studies investigated the possibility of increasing pubertal growth to gain taller final adult height in adolescents with idiopathic short stature (ISS). The pattern of pubertal growth, its relation to sex maturity rating and factors affecting them has been addressed in this review. The results of different trials to increase final adult height of adolescents using different hormones have been summarized. These data enables Endocrinologists to give in-depth explanations to patients and families about the efficacy and clinical significance as well as the safety of using these therapies in the treatment of adolescents with ISS.

Validation of automatic bone age determination in children with congenital adrenal hyperplasia

BACKGROUND

Determination of bone age is routinely used for following up substitution therapy in congenital adrenal hyperplasia (CAH) but today is a procedure with significant subjectivity.

OBJECTIVE

The aim was to test the performance of automatic bone age rating by the BoneXpert software package in all radiographs of children with CAH seen at our clinic from 1975 to 2006.

MATERIALS AND METHODS

Eight hundred and ninety-two left-hand radiographs from 100 children aged 0 to 17 years were presented to a human rater and BoneXpert for bone age rating. Images where ratings differed by more than 1.5 years were each rerated by four human raters.

RESULTS

Rerating was necessary in 20 images and the rerating result was closer to the BoneXpert result than to the original manual rating in 18/20 (90 %). Bone age rating precision based on the smoothness of longitudinal curves comprising a total of 327 data triplets spanning less than 1.7 years showed BoneXpert to be more precise (P<0.001).

CONCLUSION

BoneXpert performs reliable bone age ratings in children with CAH.

Bone age assessment: automated techniques coming of age?

Bone age determination from hand radiographs is one of the oldest radiographic procedures. The first atlas was published by Poland in 1898, and to date the Greulich Pyle atlas, although it dates from 1959, is still the most commonly used method. Bone age rating is time-consuming, suffers from an unsatisfactorily high rater variability, and therefore already 25 years ago it was proposed to replace the manual rating by an automated, computerized method, a field nowadays referred to as computer-aided diagnosis (CAD). The pursuit of this goal reached a first stage of accomplishment in 1992-1996 with the presentation of several systems. However, they had limited clinical value, and efforts in CAD research were increasingly focused on lesion detection for cancer screening. It was only in 2008 that a fully-automated bone age method was presented, which appears to be clinically acceptable. In this paper we consider the requirements that should be met by an automated bone age method and review the state of the art. Integration in PACS and saving time are important factors for radiologists. But it is the validation of the methods which poses the greatest challenge, because there is no gold standard for bone age rating, and the direct comparison to manual rating is therefore not sufficient for demonstrating that manual rating can be replaced by automated rating. One needs additional studies assessing the precision of a method and its accuracy when used for adult height prediction, which serves as an objective.

Treatment of children and adolescents with idiopathic short stature

Idiopathic short stature (ISS) is defined as shortness in childhood without a specific cause. ISS may be familial or nonfamilial and may be associated with or without delay of pubertal development. Treatment can be considered in an attempt to reduce the psychological burden caused by short stature in childhood and adult life. If counselling alone is not sufficient, medical modifications of the growth process can be attempted. In cases with pubertal delay, sex steroids, such as testosterone and oxandrolone, can favourably influence height velocity and growth tempo, although adult height is not affected. Medications that prolong the process of growth--for example, gonadotropin-releasing hormone agonists or aromatase inhibitors--might increase adult height, but findings to date are still experimental. Growth hormone therapy is approved for the treatment of very short children with reduced adult height expectation, as evidence has accumulated that this therapy can increase height in childhood and in adult life. Sensitivity to growth hormone is impaired in patients with ISS; therefore, doses higher than a replacement dose have to be applied. This treatment still needs to be optimized in terms of efficacy, cost-effectiveness and long-term safety. A debate is ongoing concerning the psychological benefit of height increase, with clinicians warning against the medicalization of a deviation in height.

Prediction of adult height by Tanner-Whitehouse method in young Caucasian male athletes

BACKGROUND

Although the accuracy of final height prediction using skeletal age development has been confirmed in many studies for children treated for congenital primary hypothyroidism, short normal children, constitutionally tall children, no studies compared the predicted adult height at young age with final stature in athletic population.

AIM

In this study, the intention was to investigate to what extent the Tanner-Whitehouse (TW) method is adequate for prediction of final stature in young Caucasian male athletes.

DESIGN

Prospective observational study.

METHODS

Plain radiographs of the left hand and wrist were obtained from 477 athletic children (ranging in age from 8.0 to 17.9 years) who came to the outpatient clinic between 2000 and 2011 for adult height estimation, with no orthopedic trauma suspected. Adult height was estimated using bone age rates according to TW method. Height was measured both at baseline and follow-up (at the age of 19 years).

RESULTS

No significant difference was found between the estimated adult height (184.9 ± 9.7 cm) and final stature (185.6 ± 9.6 cm) [95% confidence interval (CI) 1.61-3.01, P = 0.55]. The relationship between estimated and final adult height was high (r = 0.96). Bland-Altman analysis confirmed that the 95% of differences between estimated adult height and final stature lie between limits of agreement (mean ± 2 SD) (-5.84 and 4.52 cm).

CONCLUSION

TW method is an accurate method of predicting adult height in male normal-growing athletic boys.

Comparison of radiogrammetrical metacarpal indices in children and reference data from the First Zurich Longitudinal Study

BACKGROUND

A number of radiogrammetrical metacarpal indices are in use, some of which have been adapted for children.

OBJECTIVE

The purpose of this study was to compare four known indices-bone mineral density (BMD), relative cortical area, Exton-Smith index, bending breaking resistance index-and the more recently defined pediatric bone index (PBI) according to the two criteria of minimum height dependence and minimum variability in children of equal bone age.

MATERIALS AND METHODS

A total of 3,121 left-hand radiographs from 231 healthy Caucasian children ranging in age from 3 to 19 years old were analysed using BoneXpert®, a programme for automatic analysis of hand radiographs and assessment of bone age.

RESULTS

Dependence on height for chronological age or bone age and the mean relative standard deviation were lowest in the PBI for both genders pooled. The differences in height dependence were statistically significant and are shown to be clinically relevant. Reference data for PBI are presented.

CONCLUSION

PBI may be a better indicator than BMD for bone health in children; however, verification in a clinical group is needed.

Further delineation of 17p13.3 microdeletion involving CRK. The effect of growth hormone treatment

Recently, a 17p13.3 microdeletion syndrome characterized by significant postnatal growth retardation, mild to moderate mental retardation and facial dysmorphic manifestations has been delineated to a small region within the area of the Miller-Dieker syndrome critical region. We report a boy with a 284 kb deletion within the Miller-Dieker critical region including CRK, but not involving YWHAE and TUSC5. He showed mental retardation and had significant postnatal growth retardation. Further, he had slight facial and limb abnormalities. Cerebral MRI, including visualization of the pituitary gland, disclosed no abnormalities. The findings in the present case indicate, that CRK may also be involved in the facial phenotype of the 17p13.3 microdeletion syndrome, and that CRK, and not YWHAE, seems to be involved in limb malformations. The effect of growth hormone treatment in CRK-deficient children is discussed.