Assessment of bone quality by quantitative ultrasound of proximal phalanges of the hand and fracture rate in children and adolescents with bone and mineral disorders

Effects of antiepileptic therapy on bone mineral status evaluated by phalangeal quantitative ultrasound in pediatric patients with epilepsy and motor impairment

BACKGROUND

In epileptic patients with motor disability, it's difficult to disentangle the effects of antiepileptic drugs (AEDs) on bone health from those provoked by impaired mobility. The aim of this study was to evaluate the effects of AEDs on bone mineral status by phalangeal quantitative ultrasound (QUS), a no-radiation and non-invasive method, in pediatric patients with motor impairment and epilepsy.

METHODS

We enrolled 56 patients (31 females, 25 males) with epilepsy and motor impairment and 24 children with only motor disability (13 females, 11 males). Patients were stratified by Gross Motor Function Classification System Scale (GMFCS) in 4 groups: group A1 with epilepsy and mild motor impairment (GMFCS levels I-II), group A2 with only mild motor impairment, group B1 with epilepsy and severe motor impairment (GMFCS levels III-V), group B2 with only severe motor impairment. The bone mineral status was evaluated by phalangeal QUS and amplitude-dependent speed of sound (AD-SoS) Z-score was calculated for each patient.

RESULTS

The four groups showed no significant differences in age, gender and 25-hydroxyvitamin D levels. The group B1 had a statistically lower amplitude-dependent speed of sound Z-score as compared to group A2 (P<0.05). The multivariate analysis of independent factors revealed a significant correlation between amplitude-dependent speed of sound Z-score and Gross Motor Function Classification System levels (P=0.004). The mean Z-score value decreased by 0.53, increasing the motor impairment.

CONCLUSIONS

The bone mineral status measured as AD-SoS strongly correlates with severity of motor disability evaluated by GMFCS as compared to antiepileptic therapy and 25-hydroxyvitamin D levels.

Can Ultrasonographic Measurement of Bone Cortical Thickness Predict Osteoporosis?

RATIONALE AND OBJECTIVES

In this study, we aimed to describe a more accessible and safe diagnostic tool for osteoporosis or osteopenia diagnosis. We utilized cortical thickness (CoT) measurement of various bones via ultrasonography and evaluated the method's accuracy relative to bone mineral density (BMD) results determined by dual-energy X-ray absorptiometry (DXA).

MATERIALS AND METHODS

A total of 200 volunteers (all female) who agreed to participate in the study and had undergone BMD measurement (femoral or vertebral) were included in the study. Patients with normal BMD result (≥-1.0 T-score) were defined as controls. CoT measurements were made from three bones (radius, tibia, and second metatarsal) for each patient via ultrasonography.

RESULTS

Radius CoT and tibial CoT measurements of both femoral and vertebral osteoporotic or osteopenic patients were significantly higher compared to controls. Second metatarsal CoT of femoral osteoporotic and osteopenic patients was also found to be significantly higher than the control group. We found tibia CoT and radius CoT to have high sensitivity and positive predictive value in identifying patients with abnormal femoral T-scores (<-1). In multivariable analyzes, radius CoT was found to be independently predictive in distinguishing patients with abnormal T-score (<-1) from controls in both the femur and vertebral BMD groups.

CONCLUSION

Radius CoT and tibia CoT values appear to have value in predicting patients with abnormal T-scores measured via DXA. This method may be a very simple technique that can be used for early detection of osteoporosis and osteopenia, but its results need to be supported by more comprehensive studies.

The Impact of Environmental and Genetic Factors on Bone Quality in Monozygotic and Dizygotic Twins

The purpose of the research was to assess the genetic and environmental influences on bone properties. One hundred thirty-two pairs of twins (99/33 monozygotic/dizygotic) underwent anthropometric measurements and phalangeal quantitative ultrasound (DBM Sonic 1200, Igea, Italy) measuring the amplitude speed of sound (AD-SoS, m/s). The mean age was 16.78 ± 12.35 years for monozygotic twins and 14.30 ± 8 years for dizygotic. Interpair and intrapair correlations between twins were calculated. In the groups of monozygotic and dizygotic twins, Ad-SoS correlated significantly with age (r = 0.56−0.73, p < 0.05), weight (r = 0.73−0.78, p < 0.05), and height (r = 0.80−0.81, p < 0.05). The strongest intrapair correlation (r = 0.99−0.998) was noted in monozygotic females for Ad-SoS, weight, and height. There was a statistically significant correlation between the intrapair difference of Ad-SoS and age but only in the groups of monozygotic and dizygotic females (r = 0.281, r2 = 0.079, and p = 0.028; r = 0.544, r2 = 0.296, and p = 0.01, respectively). After age adjustment, it was estimated that 28.62% of Ad-SoS in women and 13.2% of Ad-SoS in men was explained by genetic influence, leading to the conclusion that Ad-SoS changed with age, weight, and height. The strongest correlation between pairs of twins was observed in monozygotic twins. The differences in bone values between female twins arose with age, which indicated the role of environmental factors.

The use of quantitative ultrasound in a tertiary-level children hospital: role in the follow-up of chronically ill patients

PURPOSE

To evaluate the use of QUS for the bone status assessment in children cared because of a chronic disease such as: inherited metabolic disorder, kidney disease and endocrine defect and considered by the attending physician as at specific risk.

METHODS

QUS outputs were calculated for each disorder and compared to: sex, age, Tanner stage, Z-score for height, weight and BMI (body mass index).

RESULTS

One-hundred-sixty-eight subjects aged between 3.5 and 18 years met the inclusion criteria. The overall bone quality indexes were under the normal range in all the groups considered. Impairment of bone quality parameters was more evident in the group of patients with inherited metabolic disorders, in which 65% of patients in charge were studied by QUS. Older age and sexual development were associated with less pronounced bone quality impairment, as measured by QUS, in the vast majority of conditions. Overall, the diseases for which the prediction of outcome was the strongest were: hyperphenylalaninemia, nephrotic syndrome and insulin dependent diabetes mellitus.

CONCLUSIONS

QUS is capable to provide information on skeletal status in children. Initial evaluation by QUS may allow defining patients with chronic disorders who deserve further, more invasive diagnostic studies. Inherited metabolic disorders warrant specific attention and strict monitoring for their potential effect on bone.

Fracture prevalence in thalassemia: a systematic review and meta-analysis

BACKGROUND

Multiple observational studies have reported high prevalence of fracture in patients with thalassemia. However, most of these studies have included limited number of patients, and only few of them have reported prevalence of fracture among patients with different types and severity of thalassemia.

OBJECTIVE

This systematic review and meta-analysis was conducted to summarize all available data of fracture prevalence among patients with thalassemia.

METHODS

A systematic review was conducted using EMBASE and MEDLINE databases from inception to June 2021 to determine studies that reported prevalence of fracture in thalassemia patients. The pooled prevalence with 95% confidence interval (95%CI) of fracture across studies was determined using a random-effect, generic inverse variance method.

RESULTS

After two rounds of systematic review, a total of 25 studies with 4934 patients were included in the meta-analysis. The pooled prevalence of fracture among patients with thalassemia was 16% (95%CI, 15-17%, I² = 94.3%). The subgroup analyses showed that the pooled prevalence of fracture was 4% (95%CI, 2-6%; I² = 70.4%) among patients with alpha thalassemia, 17% (95%CI, 16-19%; I² = 93.2%) among patients with beta thalassemia, 18% (95%CI, 16-19%; I² = 89.0%) among patients with transfusion-dependent thalassemia, and 7% (95%CI, 4-10%; I² = 94.2%) among patients with non-transfusion-dependent thalassemia.

CONCLUSION

Fracture is common in patients with thalassemia, and may be more prevalent in beta thalassemia and transfusion-dependent thalassemia than in alpha thalassemia and non-transfusion-dependent thalassemia.

EFFECTS OF COMBAT SPORTS ON BONE MASS: SYSTEMATIC REVIEW

ABSTRACT Objective To determine the influence of combat sports on bone mass. Methods A systematic review was performed according to the PRISMA method, with searches in the Pubmed, Bireme, Embase and Web of Science databases covering the period 1900 to 2015, using the keywords “martial arts”, “fight”, “combat”, “karate”, “kung fu”, “tae kwon do”, “judo”, “aikido”, “bone mass”, “bone health”, “bone tissue”, “bone density”, and “bone mineral contents”. The articles were searched for and retrieved electronically and manually, by two independent reviewers. Results Seventy-nine articles were identified, of which 25 were duplicates, leaving 54 for reading and evaluation of the titles; next, articles about diseases such as bone and/or orthopedic injuries, maxillofacial, surgeries, fractures, osteoporosis and osteopenia in women, prevention of falls, and physical fitness were excluded, leaving 15 articles. Of the articles selected and retrieved in full, all were published between 2002 and 2015. One article was a case control study; two were longitudinal studies, two were randomized studies; and 10 were cross-sectional studies. A total of 1368 children, adolescents, adults and elderly subjects were involved in combat sports and had bone evaluation by imaging. Factors such as calorie intake, calcium and/or vitamin D, intensity and volume of the exercise, hormonal aspects as bone markers, and characteristics of menopause are not conclusive in relation to bone mass, and further studies are needed. Conclusion The practice of combat sports shows a significant improvement in bone mass at all ages. Level of Evidence III, Therapeutic study – Investigation of treatment results.

Bone status in relation to ambulatory performance in girls with Rett syndrome: a 10-year longitudinal study

BACKGROUND

Low bone mass is a frequent and early complication of girls with Rett syndrome. As a consequence of the low bone mass, Rett patients are at an increased risk of fragility fractures. This study aimed to investigate the long-term influences of mobility on bone status in girls with Rett syndrome.

METHODS

In 58 girls with Rett syndrome, biochemical parameters and quantitative ultrasound parameters at phalanges (amplitude-dependent speed of sound: AD-SoS and bone transmission time: BTT) were measured at baseline and after 5 and 10 years. The subjects were divided into two groups: nonambulatory (n = 28) and ambulatory (n = 30).

RESULTS

In nonambulatory Rett subjects, the values of AD-SoS and BTT were significantly lower than in ambulatory Rett subjects at each time point. However, during the 10-year follow-up both ambulatory and nonambulatory Rett patients showed a similar worsening in their bone status.

CONCLUSION

This longitudinal study suggests that both ambulatory and nonambulatory Rett subjects present a progressive deterioration of bone status as assessed by quantitative ultrasound parameters, and the ambulatory impairment and the nutritional status seem to play a key role in the deterioration of bone status.

Quantitative Ultrasound of Proximal Phalanxes in Childhood Acute Lymphoblastic Leukemia Survivors

Reduced bone mineral density (BMD) is a well-known complication in childhood acute lymphoblastic leukemia (ALL) survivors; the optimal method to assess BMD is still debated. We studied BMD by quantitative ultrasound (QUS) in 72 ALL survivors, and evaluated any correlation with cumulative doses of steroids and cytotoxic agents. Mean age at diagnosis was 61±45 months, while mean age at QUS was 318.3±129.6 months; mean period of follow-up was 41.2±37.8 months. Mean amplitude-dependent speed of sound z-score was -1.22±1.19. Ten survivors (13.8%) presented a z-score below -2 SD. A negative correlation was found between amplitude-dependent speed of sound z-score and age at diagnosis (P=0.01). A positive correlation was observed with length of follow-up (P=0.01). No correlation was found with cytotoxic drugs. This study represents the largest cohort of childhood ALL survivors studied by QUS. Our results suggest that QUS for its characteristics of being radiation free may be an effective option to assess BMD in pediatric age. In addition, our data outline the importance to improve the awareness about the specific expression of this complication in the pediatric age, concerning the major determinants of bone impairment, which are the disease itself and the phase of bone growth when the disease occurs.

Bone Geometry, Quality, and Bone Markers in Children with Type 1 Diabetes Mellitus

Adults with Type 1 diabetes mellitus show a high risk of bone fracture, probably as a consequence of a decreased bone mass and microarchitectural bone alterations. The aim of the study was to investigate the potential negative effects of type 1 diabetes on bone geometry, quality, and bone markers in a group of children and adolescents. 96 children, mean age 10.5 ± 3.1 years, agreed to participate to the study. Bone geometry was evaluated on digitalized X-rays at the level of the 2nd metacarpal bone. The following parameters were investigated and expressed as SDS: outer diameter (D), inner diameter (d), cortical area (CA), and medullary area (MA). Bone strength was evaluated as Bending Breaking Resistance Index (BBRI) from the geometric data. Bone turnover markers (PINP, CTX-I, and BAP), sclerostin, Dkk-1, PTH, and 25OH-Vitamin D were also assessed. A group of healthy 40 subjects of normal body weight and height served as controls for the bone markers. D (- 0.99 ± 0.98), d (- 0.41 ± 0.88), CA (- 0.85 ± 0.78), and MA (- 0.46 ± 0.78) were all significantly smaller than in controls (p < 0.01). BBRI was significantly lower (- 2.61 ± 2.18; p < 0.0001). PTH, PINP, and BAP were higher in the diabetic children. Multiple regression analysis showed that CA and D were influenced by insulin/Kg/day and by BMI, while d was influenced by PINP only. Type 1 diabetic children show smaller and weaker bones. The increased bone turnover could play a key role since it might amplify the deficit in bone strength associated with the inadequate osteoblastic activity caused by the disease itself.

Assessment of Lactose-Free Diet on the Phalangeal Bone Mineral Status in Italian Adolescents Affected by Adult-Type Hypolactasia

Adult-type hypolactasia (ATH) is a clinical syndrome of primary lactase deficiency. A lactose-free diet is advisable to avoid the symptoms linked to the condition, but this potentially creates problems for optimal bone mineralization due to reduced calcium intake. To evaluate the effect of the lactose-free diet on the bone mineral status (BMS), we compared the phalangeal BMS of adolescents with ATH to that of peers on a normal diet. Also, we analyzed the correlations between BMS and dietary behavior, physical exercise, and calcium and vitamin D intake. A total of 102 cases and 102 healthy controls filled out a diet record and underwent phalangeal Quantitative Ultrasound (QUS). No difference in BMS was observed. The time spent on lactose-free diet (4.8 ± 3.1 years) was inversely correlated to the BMS. More than 98% of cases consumed lactose-free milk, but calcium and vitamin D intake were significantly lower. Calcium intake was correlated to physical exercise but not to BMS. Our results suggest that a lactose-free diet does not affect the phalangeal BMS of adolescents with primary lactase deficiency when their diet includes lactose-free cow’s milk. However, there is still a significantly lower calcium intake than in the population reference. The inverse correlation observed between the BMS and the time spent on a lactose-free diet suggests that a long-term follow-up is advisable.

Constitutional bone impairment in Noonan syndrome

Noonan syndrome (NS) is an autosomal dominant trait characterized by genotypic and phenotypic variability. It belongs to the Ras/MAPK pathway disorders collectively named Rasopathies or neurocardiofaciocutaneous syndromes. Phenotype is characterized by short stature, congenital heart defects, facial dysmorphisms, skeletal and ectodermal anomalies, cryptorchidism, mild to moderate developmental delay/learning disability, and tumor predisposition. Short stature and skeletal dysmorphisms are almost constant and several studies hypothesized a role for the RAS pathway in regulating bone metabolism. In this study, we investigated the bone quality assessed by phalangeal quantitative ultrasound (QUS) and the metabolic bone profiling in a group of patients with NS, to determine whether low bone mineralization is primary or secondary to NS characteristics. Thirty-five patients were enrolled, including 20 males (55.6%) and 15 females (44.5%) aged 1.0-17.8 years (mean 6.4 ± 4.5, median 4.9 years). Each patients was submitted to clinical examination, estimation of the bone age, laboratory assays, and QUS assessment. Twenty-five percent of the cohort shows reduced QUS values for their age based on bone transmission time. Bone measurement were adjusted for multiple factors frequently observed in NS patients, such as growth retardation, delayed bone age, retarded puberty, and reduced body mass index, potentially affecting bone quality or its appraisal. In spite of the correction attempts, QUS measurement indicates that bone impairment persists in nearly 15% of the cohort studied. Our results indicate that bone impairment in NS is likely primary and not secondary to any of the phenotypic traits of NS, nor consistent with metabolic disturbances. © 2017 Wiley Periodicals, Inc.

Imaging methods for bone mass evaluation during childhood and adolescence: an update

The objective of the work was to prepare an update on imaging methods for bone evaluation during childhood and adolescence. The text was based on original and review articles on imaging methods for clinical evaluation of bone mass in children and adolescents up to 20 years old. They were selected from BIREME and PUBMED by means of the following keywords: bone density; osteoporosis/diagnosis; densitometry; tomography; ultrasonography; magnetic resonance imaging; and radiogrammetry and published in Portuguese or English, in the last 10 years (2006-2016). The article was organized into topics with the description of peculiarities, advantages and disadvantages of each imaging method and their possible clinical applicability. Despite the emergence of new technologies, dual energy X-ray absorptiometry (DXA) remains the gold standard method for low bone mass diagnosis in all age groups. However, interpretation is complex in children and adolescents and demands skilled people. Quantitative computed tomography (QCT) [central QCT, peripheral QCT (pQCT) and high resolution-pQCT (HR-pQCT)] and magnetic resonance imaging (MRI) evaluate real bone density, but are not yet available for routine use. Quantitative bone ultrasound (QUS) shows good perspectives for its use in primary prevention actions. Automated radiogrammetry shows promise as a method able to flag individuals who might benefit from a complete bone assessment, but the clinical value of the measures still needs to be established.

Mechanical, biochemical, and dietary determinants of the functional model of bone development of the radius in children and adolescents

This study examined the degree to which various mechanical, biochemical, and dietary factors are related to nonweight bearing bone properties in 172 healthy peri-pubertal children (age, 11.7 ± 2.0 years). Dominant radial speed of sound (rSOS) was measured by transaxial quantitative ultrasound at distal radius. Potential modulating factors included somatic maturity offset (years from age of peak height velocity), grip strength, forearm lean cross-sectional area (CSA), physical activity, nutritional intake, and amino-terminal cross-linking propeptide (NTx), reflecting bone resorption. In a hierarchical regression, grip strength adjusted for CSA was the second most important predictor of rSOS after the maturity offset (β = 0.22 and β = 0.33, respectively; R² = 0.16). When relative grip strength was added to the model the contribution of sex was no longer significant. Calcium intake was a significant predictor of rSOS only after NTx was accounted for in the model (β = 0.17, R² = 0.21). This may suggest that calcium's effects on the muscle-bone unit may be modulated through bone resorption. In the final model, relative grip strength together with maturity offset, dietary calcium, and NTx explained up to 21% of the variance in rSOS in this cohort of children. Therefore, during the peri-pubertal stage, size-adjusted forearm muscle strength is related to radial bone strength after controlling for maturity, with calcium intake having a potential indirect association through NTx.

The impact of underlying disease on fracture risk and bone mineral density in children with rheumatic disorders: A review of current literature

Childhood rheumatic diseases are associated with negative impacts on the skeleton, related to both the underlying illness and complications of therapy. The effects of medications like corticosteroids are well recognized, leading to reductions in bone mineral density and bone strength and concomitant increases in bone fragility and fracture risk. The impact of factors directly attributable to the underlying disease is not as well recognized. In this article, we review relevant literature to identify data which can contribute to an understanding of the impact of childhood rheumatic disease on the skeleton. We conclude that childhood rheumatic diseases are associated with reductions in bone mineral density and increased risk of vertebral and non-vertebral fractures. These data are strongest for juvenile arthritis, while conclusions are more limited for other rheumatic illnesses, like juvenile systemic lupus erythematosus or juvenile dermatomyositis, due to small numbers of patients studied. Finally, we make recommendations for areas in need of further research. These include the need for long-term longitudinal studies and for data to be collected in patients who have not been treated with corticosteroids.

Greater Calcium Intake is Associated with Better Bone Health Measured by Quantitative Ultrasound of the Phalanges in Pediatric Patients Treated with Anticonvulsant Drugs

We aimed to investigate and compare the effects of chronic antiepileptic therapy on bone health in pediatric patients using quantitative ultrasound of the phalanges (QUS) and controlling for potential confounding factors, particularly nutrient intake. The amplitude-dependent speed of sound (Ad-SoS) was measured in 33 epileptic children and 32 healthy children aged 6.5 ± 3.1 and 6.3 ± 1.1 (mean ± SD) years, respectively. There were no significant differences in the demographics such as age, weight and height between epileptic children and the control group children. None of the children in the epileptic or the treatment group were found to have a vitamin D deficiency. There were no significant differences in laboratory tests between groups. Lower QUS figures were found in the epileptic children (p = 0.001). After further adjustment for potential confounders such age, height, weight, calcium intake, vitamin D intake, physical activity and sex, the differences remained significant (p < 0.001). After further classification of the participants based on the tertile of calcium intake, no significant differences were found between patients and healthy controls in the greatest tertile of calcium intake (p = 0.217). We conclude that anticonvulsant therapy using valproate may lead to low bone mass in children and that an adequate intake of calcium might counteract such deleterious effects.

Brazilian pediatric reference data for quantitative ultrasound of phalanges according to gender, age, height and weight

Aims

To establish normative data for phalangeal quantitative ultrasound (QUS) measures in Brazilian students.

Methods

The sample was composed of 6870 students (3688 females and 3182 males), aged 6 to 17 years. The bone status parameter, Amplitude Dependent Speed of Sound (AD-SoS) was assessed by QUS of the phalanges using DBM Sonic BP (IGEA, Carpi, Italy) equipment. Skin color was obtained by self-evaluation. The LMS method was used to derive smoothed percentiles reference charts for AD-SoS according to sex, age, height and weight and to generate the L, M, and S parameters.

Results

Girls showed higher AD-SoS values than boys in the age groups 7–16 (p<0.001). There were no differences on AD-SoS Z-scores according to skin color. In both sexes, the obese group showed lower values of AD-SoS Z-scores compared with subjects classified as thin or normal weight. Age (r² = 0.48) and height (r² = 0.35) were independent predictors of AD-SoS in females and males, respectively.

Conclusion

AD-SoS values in Brazilian children and adolescents were influenced by sex, age and weight status, but not by skin color. Our normative data could be used for monitoring AD-SoS in children or adolescents aged 6–17 years.

Prematurity and low birth weight lead to altered bone geometry, strength, and quality in children

PURPOSE

Prematurity and low birth weight are associated with a decrease in bone mass. Aim of the study was to investigate bone geometry, strength, and quality in children born at term small for gestational age (term SGA), premature appropriate for gestational age (prem AGA), and premature SGA (prem SGA).

METHODS

91 patients (46 f, 45 m), mean age 11.28 years, height SDS 0.03 ± 0.21, and BMI SDS -0.31 ± 0.19. 20 were term SGA, 22 prem SGA, and 49 prem AGA. Bone geometry was assessed on the 2nd metacarpal bone, by evaluating the outer and inner diameter, the cortical area, medullary area, metacarpal index, cross-sectional area, and bone strength. Bone quality was evaluated by ultrasound and expressed as amplitude-dependent speed of sound and bone transmission time (BTT).

RESULTS

Term SGA, prem SGA, and prem AGA had values of bone geometry, strength, and quality significantly lower than our reference range (p < 0.05). Findings in the three groups were similar, apart from BTT, which was significantly reduced in prem SGA (p < 0.05). Fat percentage was the main determinant of BTT.

CONCLUSIONS

Children born either prematurely or SGA seem to have smaller and weaker bones. Those born both premature and SGA were the most affected.

Evaluation of impact of steroid replacement treatment on bone health in children with 21-hydroxylase deficiency

There are conflicting data regarding the potential impact of chronic glucocorticoid (GC) therapy on the bone mineral density of patients with congenital adrenal hyperplasia (CAH). Previous studies performed by dual-energy X-ray absorptiometry reported conflicting results. The purpose of this study was to assess the impact of chronic GC replacement treatment in children with classical and non classical CAH due to 21-hydroxylase deficiency (21-OHD) by quantitative ultrasonometry (QUS), an easy, cheap, and radiation-free technique. The study population consisted of nineteen 21-OHD patients (nine males) on lifelong GC treatment. Anthropometric, hormonal, and treatment data were recorded for each patient, and bone quality was assessed by QUS measurements. QUS findings (amplitude-dependent speed of sound and bone transmission time) were normal in 21-OHD patients and did not correlate with duration of treatment, daily, total, and yearly hydrocortisone dose. Furthermore, no significant correlation was found between QUS findings and 17α-hydroxy progesterone, Δ4-androstenedione, and testosterone levels. In conclusion, our results provide reassurance that currently used replacement doses of GC do not have a major impact on bone in patients with CAH. QUS seems to be a reliable tool for screening of bone health in children with 21-OHD.

Ultrasound method applied to characterize healthy femoral diaphysis of Wistar rats in vivo

A simple experimental protocol applying a quantitative ultrasound (QUS) pulse-echo technique was used to measure the acoustic parameters of healthy femoral diaphyses of Wistar rats in vivo. Five quantitative parameters [apparent integrated backscatter (AIB), frequency slope of apparent backscatter (FSAB), time slope of apparent backscatter (TSAB), integrated reflection coefficient (IRC), and frequency slope of integrated reflection (FSIR)] were calculated using the echoes from cortical and trabecular bone in the femurs of 14 Wistar rats. Signal acquisition was performed three times in each rat, with the ultrasound signal acquired along the femur's central region from three positions 1 mm apart from each other. The parameters estimated for the three positions were averaged to represent the femur diaphysis. The results showed that AIB, FSAB, TSAB, and IRC values were statistically similar, but the FSIR values from Experiments 1 and 3 were different. Furthermore, Pearson's correlation coefficient showed, in general, strong correlations among the parameters. The proposed protocol and calculated parameters demonstrated the potential to characterize the femur diaphysis of rats in vivo. The results are relevant because rats have a bone structure very similar to humans, and thus are an important step toward preclinical trials and subsequent application of QUS in humans.

Evidence-based outcomes on diagnostic accuracy of quantitative ultrasound for assessment of pediatric osteoporosis - a systematic review

BACKGROUND

Dual-energy absorptiometry (DXA) is the current reference standard for assessing pediatric osteoporosis; however due to its areal nature, it has limitations. Thus, quantitative ultrasound (QUS), a modality free of ionizing radiation, has been proposed as a potential surrogate for DXA.

OBJECTIVE

To semi-quantitatively assess the diagnostic accuracy of QUS for evaluating pediatric osteoporosis according to the U.S. Preventive Services Task Force guidelines.

MATERIALS AND METHODS

We retrieved articles on the diagnostic accuracy of quantitative US for assessing abnormal bone quality or quantity in patients of mean age ≤19 years from MEDLINE, EMBASE and Cochrane Library CCTR databases. Evidences were analyzed for reliability, construct and criterion validity, and responsiveness of quantitative US, according to the following questions: (1) How reliable is the acquisition of QUS measurements? (2) Is QUS diagnostically accurate to characterize bone strength and quality in osteoporotic children? (3) Is QUS sensitive to detect changes in bone status over time? (4) Is QUS able to predict future skeletal fractures/degeneration? Three reviewers independently evaluated the quality of reporting and methodological quality using the Standards for Reporting of Diagnostic Accuracy (STARD) and the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tools.

RESULTS

Out of 262 retrieved references (215 unique), we included 28 studies (1,963 patients; 807 reported boys and 761 girls, others unspecified; reported mean age, 0-19 years). The mean quality of reporting score was "excellent" in 24/28 (86%) studies; 11/28 (39%) studies had "adequate" research design quality.

CONCLUSION

There is no evidence of the diagnostic value of QUS at the present time despite the overall excellent and adequate research design quality of primary studies. Although QUS can produce reliable measurements, insufficient evidence has been reported to support other clinimetric properties of this technique.

Bone health in children and adolescents with steroid-sensitive nephrotic syndrome assessed by DXA and QUS

BACKGROUND

The management of steroid-sensitive nephrotic syndrome (SSNS) requires treatment with high-dose glucocorticoids (GCs), but GC usage causes the most frequent form of drug-induced osteoporosis. The aim of our study was to evaluate the impact of GCs on bone mineralization in patients with SSNS using two diagnostic tools, dual-energy X-ray densitometry (DXA) and quantitative ultrasound (QUS), and to compare the diagnostic efficacy of these two imaging tools.

METHODS

A total of 30 children with SSNS (age 5.20 ± 2.20 years) were evaluated at the start (T0) and after 1 (T1), 2.44 ± 0.75 (T2, 18 patients) and 5.96 ± 2.33 years (T4, 12 patients) of GC treatment. Patients who stopped at T2 were also evaluated at the 1-year timepoint after ceasing GC treatment (T3).

RESULTS

Of the patients assessed at T2, 11 had bone mineralization at the lower limit of normal versus those at T0 and T1, with bone mineralization rescue at the 1-year timepoint after GC discontinuation. At T4, 6/12 patients had densitometric parameters at the lower limit of normal values, and 3/12 patients showed reduced bone mineralization. The parameters derived from measurements of DXA and QUS were significantly related to each timepoint.

CONCLUSIONS

Patients with SSNS receiving GC therapy undergo bone status alteration related to the dosage and duration of the therapy. In terms of diagnostic efficacy, DXA and QUS were comparable, indicating that QUS is a reliable tool to evaluate bone health in children with SSNS.

A comparative study of dual-X-ray absorptiometry and quantitative ultrasonography for the evaluating bone status in subjects with Rett syndrome

Rett syndrome, an X-linked neurodevelopmental disorder primarily affecting girls, is frequently characterized by a reduced bone mineral density (BMD) with an increased risk of fragility fractures. The aim of the study was to assess bone status by DXA technique and by quantitative ultrasound (QUS) in subjects with Rett syndrome and to evaluate which DXA or QUS parameters better correlate with clinical features. In 156 Rett subjects (mean age 13.6 ± 8.2 years) and in 62 controls, we measured BMD at femoral neck (BMD-FN) and at total femur (BMD-TF). Apparent volumetric bone mineral density (vBMAD) was also calculated. In all subjects, QUS parameters at phalanges by Bone Profiler-IGEA (amplitude-dependent speed of sound: AD-SoS and bone transmission time: BTT) were evaluated. We found that both DXA parameters and QUS parameters were significantly lower in Rett subjects than in controls. All clinical characteristics were positively correlated to BMD-FN, BMD-TF, AD-SoS, and BTT (p < 0.001) but not with vBMAD-FN. All ultrasonographic parameters were significantly correlated to BMD-FN and BMD-TF, whereas vBMAD-FN showed only positive significant correlation with densitometric parameters (p < 001). In Rett subjects BMD-FN was predicted primarily by weight and movement capacity, whereas vBMAD-FN was predicted by weight, height, and calcium intake. Moreover, AD-SoS was predicted by weight, height, and age, while BTT was predicted only by height. In conclusion, in our study the performance of QUS at phalanges was similar to those of BMD at femur, therefore, both areal BMD at femur and QUS at phalanges (AD-SoS and BTT) may be equally useful in the evaluation of skeletal status in Rett patients.

Treatment of osteoporosis in children with glucocorticoid-treated diseases

Glucocorticoid induced osteoporosis (GIO) is the most frequent form of drug induced osteoporosis. Glucocorticoids affect osteoblastogenesis, osteoclastogenesis and promote the apoptosis of osteoblasts and osteocytes. A decrease of bone mineral density has been described in several pediatric diseases that require glucocorticoids, both as long-term replacement therapy, such as Congenital Adrenal Hyperplasia, and as treatment of acute phase or relapses, such as asthma, juvenile rheumatoid arthritis, inflammatory bowel diseases, systemic lupus erythematosus, organ transplantation and Steroid Sensitive Nephrotic Syndrome. The increasing number of children with GIO and at risk of fractures reflects the complex nature of this condition, and the need of development of anti-osteoporotic drugs. In this review, we focus on the mechanisms of GIO in some pediatric diseases and on treatment of osteoporosis. We also report data on new signaling pathways as potential targets for future anti-osteoporotic drugs.

A survey of steroid-related osteoporosis diagnosis, prevention and treatment practices of pediatric rheumatologists in North America

BACKGROUND

The purpose of our study is to assess practices of North American pediatric rheumatologists regarding monitoring, prevention, and treatment of low bone mineral density (BMD) in children on long-term glucocorticoid treatment. Long-term glucocorticoid therapy is associated with accelerated bone loss. Children with JIA and lupus have low baseline BMD and incident vertebral fractures commonly occur in these groups of patients even after a relatively short period of time being on systemic glucocorticoids. There are no established guidelines for identification, prevention, and treatment of glucocorticoid-induced bone loss in children.

METHODS

A cross-sectional online survey was conducted with 199 physicians who were listed in the ACR database as practicing pediatric rheumatology in North America.

RESULTS

86 physicians (43%) responded; 87% were board-certified in pediatric rheumatology. 95% used dual energy X-ray absorptiometry as their primary modality for assessing BMD. 79% "rarely" or "never" obtained a baseline BMD measurement prior to initiation of glucocorticoid therapy. 42% of respondents followed BMD annually. 93% "frequently" or "always" prescribed calcium for patients on long-term corticosteroid therapy; 81% "frequently" or "always" prescribed vitamin D. In patients diagnosed with osteoporosis, 35%-50 % of the practitioners "sometimes", "frequently" or "always" prescribed bisphosphonates. Bisphosphonates are prescribed at similar rates for male and female patients, and slightly more frequently for pubertal than for pre-pubertal patients. 96% of respondents "rarely" or "never" prescribed calcitonin for patients on long-term glucocorticoid therapy; 92% "rarely" or "never" prescribe this medication for patients with known osteopenia or osteoporosis.

CONCLUSIONS

Utilization of DXA in children on long-term corticosteroid therapy varies greatly among North American pediatric rheumatologists. Most respondents do not screen for low BMD on a regular basis despite acknowledging the risks of bone loss in this population. Broad consensus appears to be present among practitioners favoring the prescription of calcium and vitamin D for patients receiving long-term corticosteroid therapy. Relatively few respondents consistently recommend bisphosphonate therapy, even for patients with known low bone density; calcitonin is rarely used. These data underscore the need for studies to acquire specific data on bone loss, and its prevention and treatment in young patients on long-term glucocorticoid therapy.

Quantitative ultrasound applied to metacarpal bone in infants

Aim. To provide bone status assessment in infancy using quantitative ultrasound (QUS) applied to second metacarpus.

Methods. 103 healthy term infants and 3 patients with rickets, aged ≤ 12 months, underwent metacarpal QUS evaluation using QUS DBM Sonic Aurora IGEA (MO, Italy), which measures speed of sound (mcSOS) and bone transmission time (mcBTT).

Results. In the total sample, median (interquartile range) of mcSOS was 1640.00 (26.0) m/s and mcBTT 0.82 (0.21) µs. Moreover, reference values for age were obtained based on estimation of the lower and upper percentiles. We observed a statistical significant difference between groups of age for mcSOS (p = 0.016). In a multiple linear regression model, we found a relation between age at enrolment and mcSOS (β = −0.608; p = 0.000) and mcBTT (β = −0.819; p = 0.001). A positive correlation between mcSOS and mcBTT has been observed (r = 0.631; p = 0.000). All the patients with rickets showed values of mcSOS and mcBTT lower than the 10th percentile.

Conclusion. Our findings show that this new simple technique appears to be a promising tool for monitoring bone mineral status in pediatric clinical practice and in early life. Furthermore, it could be considered a useful method to investigate and to monitor the role of different factors on programming of bone health and it should be tested as a new method for monitoring subjects with rickets during therapy.

High bone mineral apparent density in children with X-linked hypophosphatemia

Bone mineral apparent density (BMAD) in children with X-linked hypophosphatemia (XLH) was evaluated, as they are unlikely to have extra-skeletal ossifications contributing to the elevated bone mineral density of the spine in adult patients. Children with XLH also had significantly higher BMAD of the spine compared to femoral neck.

INTRODUCTION

BMAD obtained by dual-energy X-ray absorptiometry scans in children with XLH was evaluated, as they are unlikely to have the extra-skeletal ossifications contributing to the elevated bone mineral density of the spine in adult patients.

METHODS

A total of 15 children with biochemically and genetically verified XLH were recruited. Anthropometric measurements were performed, and to correct for the short stature (small bones), the BMAD of the spine and the femoral neck was evaluated.

RESULTS

Z-scores of BMAD of the spine (mean (95 % CI); 2.0 (1.3-2.7); p < 0.001) were significantly elevated compared to reference children. Z-scores of the femoral neck (1.0 (-0.0 to 2.1); p = 0.059) tended to be elevated. Spine Z-scores were significantly higher than the Z-scores of the femoral neck, (paired t test, p = 0.02). BMAD of the spine was evaluated according to the Molgaard's approach; XLH children had normal bone size of the spine for age due to a normal sitting height Z-score of -0.4 (-1.0 to 0.1); p = 0.1. Z-scores of bone mineral content (BMC) of the spine for bone area were elevated (1.4 (0.8-2.1); p < 0.001). No reference data were available to allow evaluation of the BMAD of the femoral neck by the Molgaard's approach.

CONCLUSIONS

Children with XLH have an increased BMAD and a high BMC for bone area at the lumbar spine, and this was due to causes other than extra-skeletal ossifications and corrected for bone size. The BMAD of the spine was significantly higher compared to the femoral neck.

Quantitative ultrasound for predicting curve progression in adolescent idiopathic scoliosis: a prospective cohort study of 294 cases followed-up beyond skeletal maturity

Adolescent idiopathic scoliosis (AIS) is prevalent among adolescents and can carry significant morbidities. We evaluated the use of quantitative ultrasound (QUS) for predicting curve progression in patients with AIS. We recruited 294 girls with AIS at a mean age of 13.4 years, and they were prospectively followed beyond skeletal maturity for curve progression. We recorded 3 calcaneal QUS measurements at baseline, namely broadband ultrasound attenuation (BUA), velocity of sound (VOS), and stiffness index (SI). Logistic regression analysis indicated that SI, age, menarchal status, and Cobb angle were significant prognostic factors to be included in the final prediction model. The adjusted odds ratio of curve progression for Z-score of SI≦0 was 2.00 (95% CI: 1.08-3.71). The area under the ROC curve was 0.831 (95% CI: 0.785-0.877). The results of this study indicate that SI was an independent and significant prognostic factor for AIS and could be considered in addition to other prognostic factors when estimating the risk for curve progression and planning treatment for patients with AIS.

Fractures in hospitalized children

Hospitalized children have multiple risk factors for fragility fractures, related to disease pathophysiology, treatments, nutritional status and immobilization. Recognition and treatment of these risk factors are important to prevent morbidity associated with fractures and to promote current and future bone health. Many knowledge gaps remain regarding the ideal nutrition, physical activity, and medication regimens needed to optimize bone health and reduce the risk of fractures over the life course. This article reviews the pathogenesis, risk factors, treatment and prevention strategies for fractures in hospitalized infants and children.

Small metacarpal bones of low quality in obese children

OBJECTIVE

It is still not known whether fat mass excess could exert a positive effect on bone. The aim of our study was to evaluate bone strength and quality in a group of overweight and obese children and adolescents by assessing bone geometry at metacarpal bones and ultrasound at phalangeal level.

DESIGN AND PATIENTS

This is a cross sectional observational study performed in 123 subjects, aged 11.2 ± 2.9 years.

MEASUREMENTS

Digitalized X-rays were evaluated at the level of the 2nd metacarpal bone for the determination of the outer (D) and inner (d) diameter, cortical area (CA), medullary endocortical area (EA), metacarpal index (MI) and bone strength (Bending Breaking Resistance Index; BBRI). A total of 98 subjects underwent amplitude dependent speed of sound (Ad-SOS) and bone transmission time (BTT) assessment by phalangeal ultrasonography.

RESULTS

SDs for each measured parameter were as follows: Males: D = -0.71 ± 0.95, d = -0·29 ± 0.86, CA = -0.69 ± 0.69, EA = -0.32 ± 0.79, Ad-SOS = -1.14 ± 0.91, BTT = -1.17 ± 1.11 and BBRI (417 ± 151 vs 495 ± 174 mm(3) ) were all significantly lower than in controls (P < 0.05). Females: D = -1.03 ± 1.06, d = -0.38 ± 0.92, CA = -0.91 ± 0.72, EA = -0.46 ± 0.79, Ad-SOS = -1.08 ± 1.11, BTT = -0.97 ± 1.07 and BBRI (342 ± 117 vs 649 ± 318 mm(3) ) were all significantly lower than in controls (P < 0.05).

CONCLUSIONS

Obese children show an unfavourable bone geometry and a bone of low quality and reduced strength compared to controls at a nonweight bearing skeletal site. This finding seems to support a detrimental effect of fat mass on bone and explain the frequent occurrence of wrist fractures in this group of children.

Phalangeal quantitative ultrasound in 1,719 children and adolescents with bone disorders

SUMMARY

We measured bone properties by phalangeal quantitative ultrasound in 1,719 pediatric patients with bone disorders, classifying them according to fracture status. Quantitative ultrasound discriminated fractured and nonfractured pediatric patients and enabled us to stratify fractured patients into classes according to the severity of the causative trauma (spontaneous, minimal trauma, appropriate trauma fractures).

INTRODUCTION

The correlation between quantitative bone measurements and fractures is poorly established in pediatric patients with bone disorders. We correlated phalangeal quantitative ultrasound (QUS) and fracture history in children and adolescents with bone disorders and evaluated the ability of QUS to recognize fractured patients.

METHODS

Amplitude-dependent speed of sound (AD-SoS) and bone transmission time (BTT) were measured in 1,719 pediatric patients with bone disorders and related to fracture history. The patients were classified as (1) spontaneously (77), (2) minimal trauma (101), or (3) appropriate trauma fractured (206), and (4) nonfractured (1,335). The likelihood of fracture according to QUS was calculated as odds ratio per SD decrease (OR/SD), and the effectiveness in discriminating fractured patients was evaluated by receiver operating characteristic (ROC) analysis. The influence of age, sex, puberty, height, and BMI was explored by respective adjustments and multiple logistic regression.

RESULTS

Fractured patients showed significantly reduced AD-SoS and BTT standard deviation score (-0.32 ± 1.54 and -0.78 ± 1.49) compared to nonfractured subjects (0.43 ± 1.63 and -0.11 ± 1.34). QUS measurements paralleled the causative trauma severity, ranging from the lowest values in spontaneously fractured patients to normal values in appropriate trauma fractured subjects. The OR/SD were increasingly higher in appropriate trauma fractured, minimal trauma fractured, and spontaneously fractured patients. At ROC analysis, both parameters proved to have significant discrimination power in recognizing spontaneously and minimal trauma-fractured patients.

CONCLUSIONS

QUS identifies fractured pediatric patients with bone disorders, reflecting the severity of the causative trauma with a high discrimination power for fragility fractures.

Rate of trabecular bone area in 3-6-year-old children and relation to intrauterine growth

BACKGROUND

The aim of the present study was to investigate bone mass using rate of trabecular bone area (RTBA) in Japanese children to determine its relationship with indices of growth such as height and weight from before birth through childhood.

METHODS

  A cross-sectional study was conducted. The sample consisted of Japanese boys (n= 716) and girls (n= 586) aged 3-6 years. RTBA was measured using quantitative ultrasound (ultrasonic bone densitometer, Benus III; Ishikawa Seisakusho, Kanazawa, Japan). The relation between RTBA and height and weight during childhood and also at birth was assessed.

RESULTS

The average RTBA in boys was 27.7 ± 1.59% (mean ± SD) and that in girls was 27.9 ± 1.59%. RTBA significantly correlated with weight both in boys (P= 0.013) and girls (P= 0.016). Significant correlation was demonstrated between RTBA and height, especially in girls (P= 0.045). Statistical significance was shown between RTBA and birth length in boys (P= 0.015) and girls (P= 0.007), and weight at birth in boys (P= 0.014). On multiple regression analysis RTBA correlated significantly with birthweight for boys (standardized coefficient β= 0.093, P= 0.028) and birth length for girls (β= 0.122, P= 0.007).

CONCLUSION

Augmentation of bone mass is related not only to weight and height during childhood but also to prenatal factors such as growth, and possibly with nutrition in utero.

Bone mass of Spanish school children: impact of anthropometric, dietary and body composition factors

The purpose of this study was to: (a) determine the relationship between quantitative ultrasound (QUS) results and anthropometric, dietary and body composition factors and establish reference ranges for amplitude-dependent speed of sound (Ad-SoS) in the phalanges and broadband ultrasound attenuation (BUA) in the calcaneus of children from Extremadura, Spain, and (b) to present reference curves for this population. Healthy children (n = 245), aged 4-16 years, were included (124 girls and 121 boys). Phalangeal and calcaneal QUS measurements were performed using DBM Sonic Bone Profiler and McCue CUBA Clinical ultrasound devices, respectively. Weight, height and body mass index (BMI) were evaluated by anthropometric methods. Fat percentage, fat mass, lean mass (FFM) and total body water (TBWater) were evaluated by bioelectrical impedance measurements using a Holtain body composition analyzer. Food intake was evaluated by a 7-day food record. A gender analysis revealed that Ad-SoS and BUA parameters increased significantly with age and that both positively correlated with age, weight, height, BMI, FFM and TBWater. For both genders, Ad-SoS showed significant and positive correlations with age, weight, height, BMI, FFM, BUA and TBWater.

Chronic non-cholestatic liver disease is not associated with an increased fracture rate in children

Chronic liver disease in adults is a risk factor of osteoporosis, but little is known about risk of fractures in children with non-cholestatic liver disease. The aim of this study was to investigate associations among the severity of liver fibrosis, bone mass and low-energy fractures in children. History of fractures, anthropometry, and bone mass and size were examined in 39 Caucasian children (25 boys, 14 girls) aged 7.1-18 years (mean 11.9 ± 3.1) with chronic hepatitis B and liver fibrosis evidenced by liver biopsy. Severity of liver fibrosis was based on histological classification according to the method of Batts and Ludwig (mild, 1-2 scores; advanced, 3 scores) and Ishak (1-3 and 4-5 scores, respectively). Bone mineral content (BMC), density (BMD) and body composition were determined in the total body and lumbar spine using dual energy X-ray absorptiometry. Seven subjects (4 girls, 3 boys; 18% of the sample) had low BMD in the total body and lumbar spine region (Z-scores below -2.0). No associations were found among BMC, BMD, bone size and the severity of liver fibrosis. Nine boys (36% of all boys) and one girl reported repeated fractures (forearm, wrist, tibia, ankle, humerus), showing trends similar to the prevalence in general population. Fractures were neither associated with lower BMD/BMC nor with scores of liver fibrosis. Deficits in BMD in children with chronic hepatitis B are not associated with the severity of liver fibrosis. This study suggests that non-cholestatic liver disease does not increase the risk of low-energy fractures during growth. From the practical perspective, however, children with chronic liver disease should be screened for history and clinical risk factors for fractures rather than referred to bone density testing.

Impact of metabolic control on bone quality in phenylketonuria and mild hyperphenylalaninemia

OBJECTIVES

A reduction of bone mineral density of unknown etiology has been reported in phenylketonuria (PKU) by radiological techniques, whereas no data on bone density in mild hyperphenylalaninemia (HPA) are available. We aimed to assess bone condition in PKU and HPA by quantitative ultrasound (QUS), taking into account patients' clinical and biochemical features.

PATIENTS AND METHODS

Phalangeal QUS has been used for bone assessment in 78 patients affected by PKU (n = 42) or mild HPA (n = 36). For each patient, blood phenylalanine concentrations in the 2 years before the study have been recorded and related to bone assessment.

RESULTS

Overall normal bone quality has been observed in the whole study group (AD-SoS standard deviation score [SDS] 0.25 ± 1.29; BTT SDS -0.13 ± 1.08). PKU adolescents (age older than 15 years, AD-SoS SDS -0.54 ± 1.33; BTT SDS -0.85 ± 1.21) and patients with poor compliance with treatment (blood phenylalanine >10 mg/dL, AD-SoS SDS -0.47 ± 1.39; BTT SDS -0.97 ± 1.14) showed lower BTT SDS with respect to normal population (P = 0.003 and P < 0.001, respectively). Patients with PKU with good compliance with treatment (blood phenylalanine < 10 mg/dL, AD-SoS SDS 0.65 ± 1.33; BTT SDS 0.15 ± 0.94) and patients with mild HPA (AD-SoS SDS 0.44 ± 1.06 and BTT SDS 0.19 ± 0.85) showed normal bone mineral density and cortical thickness.

CONCLUSIONS

Good compliance with treatment in PKU during adolescence and adulthood is desirable because diet discontinuation is associated with bone loss. Mild HPA seems not to be complicated by bone damage.

Bone status in adolescents with type 1 diabetes

AIMS

The aim of the study was to investigate the potential negative impact of type 1 diabetes on bone status of adolescents. Bone status in adolescents with type 1 diabetes was assessed by means of quantitative ultrasound (QUS) and the influence of metabolic control and other disease-related and growth variables was analysed.

METHODS

Group I consisted of 99 pubertal (Tanner > or = 2) adolescents (49 female), aged 14.3 +/- 2.5 years, diabetes duration 4.6 +/- 2.3 years. Controls (group II) were 297 children, matched by sex and age, from a healthy population. The influence of glycated haemoglobin (current: HbA(1c)D; last year's mean: HbA(1c)Y; whole duration mean: HbA(1c)T), diabetes duration, percentage of life with disease and daily insulin requirement (DIR) on amplitude dependent speed of sound (Ad-SoS) at distal phalanges was studied.

RESULTS

In comparison to the control group, adolescents with type 1 diabetes presented significantly higher BMI SDS (0.82 [95% CI 0.54, 1.10] vs -0.06 [95% CI -0.16, 0.04] p < 0.001) and lower Ad-SoS SDS (-0.34 [95% CI -0.57, -0.11] vs -0.03 [95% CI -0.15, 0.08], p < 0.05). No correlation between Ad-SoS SDS and sex, DIR or diabetes duration was observed. The lower Ad-SoS SDS reflects reduced bone status, and the reduction was significantly more marked in those patients whose HbA(1c)T was higher than 7.0% when compared with those whose HbA(1c)T was lower.

CONCLUSIONS

Bone status of adolescents with type 1 diabetes mellitus assessed with QUS differs from that of healthy peers and is dependent on long-term metabolic control.

Quantitative ultrasound in osteoporosis and bone metabolism pathologies

Quantitative ultrasound (QUS) has been introduced in the medical field for the study of bone tissue to identify changes in the tissue that could suggest the presence of osteoporosis and bone fragility. The ultrasound technique is simple, versatile, and its low cost and lack of ionizing radiation have led to the diffusion of this method worldwide. The present article is an overview of the most relevant developments in the field of quantitative ultrasound, in clinical and experimental settings. The advantages and limitations of the present technique and suggestions for its use in the clinical practice are reported.

Prospective bone ultrasound patterns during childhood acute lymphoblastic leukemia treatment

OBJECTIVE

Bone impairment is a well-known complication in childhood acute lymphoblastic leukemia (ALL) survivors but less is known about bone dynamics during ALL therapy. We longitudinally assessed by Quantitative Ultrasound (QUS) skeletal modifications during this treatment.

MATERIALS AND METHODS

Forty-four newly diagnosed ALL children underwent bone measurement by QUS parameters BTT (Bone Transmission Time) and AD-SoS (Amplitude-Dependent Speed of Sound), mainly reliant on bone density and cortical thickness, respectively. Measurements were performed at diagnosis, and 6, 12, and 24 months thereafter. The occurrence of skeletal complications such as fractures, vertebral collapse, osteonecrosis, and osteopenia was related to measurement outcome.

RESULTS

A rapid deterioration of bone properties measured by BTT and AD-SoS was evident in the first semester of therapy (p<0.001). Subsequently, the next measurements were characterized by progressive uncoupling of the two QUS parameters (p<0.001). These were both significantly reduced at the end of therapy (p<0.001). Twelve subjects with in-treatment skeletal complications displayed an almost two-fold decrease of both parameters (p<0.001). BTT decreasing more than 1 Standard Deviation (SD) over 6 months of therapy was able to predict skeletal complication occurrence (p<0.001).

CONCLUSION

This report represents the largest longitudinal cohort systematically submitted to bone condition assessment from the beginning to the end of therapy for childhood ALL. Bone deterioration occurs early and persists throughout therapy, consistent with bone properties uncoupling. This pattern possibly reflects an initial impairment of both mineral density and cortical thickness with a subsequent recovery of this latter. QUS permits an early detection of bone deterioration and related skeletal complications in childhood ALL.

Quantitative ultrasound and dual-energy x-ray absorptiometry in children and adolescents with neurofibromatosis of type 1

Reduced areal bone mineral density (aBMD) is a common feature of neurofibromatosis type 1 (NF1). Moreover, in recent years there has been a growing interest in using quantitative ultrasound (QUS) for the evaluation of bone status. In 55 NF1 subjects (mean age: 9.3+/-5.4yr) and in 51 age- and sex-matched controls we measured aBMD at lumbar spine, at femoral neck (aBMD-FN), and at total femur (aBMD-T). Apparent volumetric bone mineral density (BMAD) was also calculated. In all subjects, QUS parameters at phalanges were evaluated. In NF1 subjects, the values of aBMD and BMAD were lower than in controls at all skeletal sites, but the difference reached statistical significance only at femoral sites (p<0.05). Both aBMD and QUS parameters were lower in those NF1 subjects with skeletal abnormalities than in those without abnormalities, but the difference was statistically significant (p<0.05) only for aBMD-FN and aBMD-T. Multiple regression analysis showed that the subjects with skeletal abnormalities had a higher risk of having bone transmission time (BTT) Z-score and aBMD Z-score at femoral sites less than -1. In conclusion, our results suggest that aBMD and QUS represent useful tools in evaluating the impairment of bone status in NF1 subjects.

Analysis of quantitative ultrasound graphic trace and derived variables assessed at proximal phalanges of the hand in healthy subjects and in patients with cerebral palsy or juvenile idiopathic arthritis. A pilot study

Amplitude-dependent speed of sound (AD-SoS) and bone transmission time (BTT) are the quantitative ultrasound (QUS) variables usually assessed at proximal phalanges of the hand to estimate bone mineral status. The aim of the study was to provide a reference database for some additional QUS variables reflecting morphology of the ultrasound graphic trace according to gender, age, height, weight, and body mass index (BMI), and to assess their clinical usefulness. Fifty-two patients (age 3.1-20.9 years) affected by cerebral palsy with spastic tetraplegia (CPST, n=38) or polyarticular active juvenile idiopathic arthritis (JIA, n=14) were examined. In addition to AD-SoS and BTT, two QUS variables derived from the morphological analysis of ultrasound graphic trace, such as energy, extrapolated from the area under the ultrasound signal received, and weighted-slope (W-slope), derived from the angular coefficient of the regression line fitting the top point of the peaks of the ultrasound signal, were measured by phalangeal QUS (DBM Sonic, IGEA). The values of all the QUS variables measured in the patients were compared with our own sex- and age-reference values (n=1083, 587 males and 496 females, aged 3-21 years). The mean values of AD-SoS, BTT, energy, and W-slope were reduced (P<0.0001) in patients as a whole compared with normative data (-2.4+/-1.2, -2.7+/-1.5, -2.5+/-1.1, -2.5+/-1.1 Z-score, respectively). Fractured patients showed lower (P<0.001-P<0.0001) values of the QUS variables than fracture-free patients (AD-SoS, -3.3+/-1.2 and -1.8+/-0.9; BTT, -3.9+/-1.7 and -1.8+/-1.1; energy, -3.2+/-1.2 and -2.2+/-0.7; W-slope, -3.4+/-1.4 and -2.2+/-0.9 Z-score, respectively). There was no difference (P=NS) between patients with CPST and those with JIA. Age and height were positively correlated with all the QUS variables (r=0.55-0.79, P<0.01-P<0.0001). QUS variables were positively correlated among them (r=0.74-0.94, P<0.0001). Age and number of fractures were independent predictors of the QUS variables (coefficients: AD-SoS, 11.466 and -17.642; BTT, 0.049 and -0.045; energy, 1.072 and -1.303; W-slope, 0.046 and -0.067; respectively). In conclusion, measurement of QUS variables derived from the morphological analysis of the ultrasound signal could give additional information in estimating bone mineral status in children and adolescents, probably reflecting some aspect related to bone structure.

Reference values for quantitative ultrasonography (QUS) of radius and tibia in healthy greek pediatric population: clinical correlations

The aim of this study was to provide reference standards for measurements of quantitative ultrasonography (QUS) of radius and tibia in normative Greek pediatric population. Analysis was performed in 1549 healthy subjects (814 girls and 735 boys) with a mean decimal age of 11.41+/-3.52 yr (range: 3.78-18.33 yr). Results showed a gradual increase of absolute values of radial and tibial speed of sound (SOS), with aging and with pubertal progressing, in both girls and boys. Gender comparison showed significantly increased SOS values measured both at radius and at tibia in girls more than 13 yr of age compared with aged-matched boys. Significant but mild correlation was noted between standard deviation scores (SDS) of SOS at radius and at tibia (r = 0.259, p < 0.001). Additionally, tibial SOS SDS were significantly negatively correlated with body mass index (BMI) SDS (r = -0.230, p < 0.001). Finally, subjects that spend more than 3h of daily "screen time" (television and personal computer) showed significantly decreased SOS values measured both at radius and at tibia. On the contrary, no correlation was observed between SOS values and the amount of physical activity reported.

Quantitative ultrasound in the assessment of skeletal status

Quantitative ultrasound (QUS) is a non-invasive technique for the investigation of bone tissue in several pathologies and clinical conditions, especially in the field of osteoporosis. The versatility of the technique, its low cost and lack of ionising radiation have led to the diffusion of this method worldwide. Several studies have been conducted in the last years to investigate the potential of QUS in multiple areas with promising results; the technique has been applied in the prediction of osteoporotic fractures, in monitoring therapies, in the investigation of secondary osteoporosis, in paediatrics, neonatology and genetics. Our review article gives an overview of the most relevant developments in the field of quantitative ultrasound, both in clinical and in experimental settings.

Dual-energy X-ray aborptiometry assessment in children and adolescents with diseases that may affect the skeleton: the 2007 ISCD Pediatric Official Positions

The Task Force focusing on the use of dual energy X-ray absorptiometry (DXA) in children and adolescents with diseases that may affect the skeleton reviewed over 300 articles to establish the basis for the Official Positions. A significant number of studies used DXA-based outcome measures to assess the effects of specific interventions and charted the natural history of incremental changes in bone size and mass in specific disease states in children. However, the utility of DXA in clinical practice has not been evaluated systematically, in large part due to the lack of a workable definition for childhood osteoporosis. Thus, in combination with the Official Positions addressing the diagnosis of osteoporosis in children, and the reporting of DXA results in children, this document presents clear guidelines from which clinicians and researchers alike can work. This report delineates a set of disorders in which it is appropriate to use DXA as part of the comprehensive assessment of skeletal health in children and adolescents, and provides guidance concerning the initiation of assessment and the frequency of monitoring. Importantly, this document also highlights significant gaps in our knowledge, emphasizing areas for future research.

The influence of gluten free diet on quantitative ultrasound of proximal phalanxes in children and adolescents with type 1 diabetes mellitus and celiac disease

A reduced bone mineral density has been reported in patients with untreated celiac disease (CD) as well as in patients with poorly controlled type 1 diabetes mellitus (T1DM). The aim of this study was to evaluate the bone mineral status by phalangeal quantitative ultrasound in 52 children and adolescents with both diseases (mean age 13.3+/-4.9 years). As a control group 50 patients with T1DM and no CD (age 12.2+/-4.0 years) were studied. The following bone parameters, amplitude-dependent speed of sound (AD-SoS) and bone transmission time (BTT) were considered and expressed as z score. Compliance to gluten free diet and long term glycemic control (mean of four determinations of HbA1c in the last year) were also assessed. The lowest mean AD-SoS z score values were found in patients with T1DM and CD, who reported transgressions to gluten free diet and exhibited positivity for serum anti-tissue transglutaminase antibodies (tTG) and/or endomysial antibodies (EmA), compared with patients with occasional transgressions but negative for anti-tTG and/or -EmA, patients strictly adherent to the diet, and patients who suffered only from diabetes (ANOVA p=0.021). No difference was found between patients with diabetes alone and patients with both diseases strictly adherent to gluten free diet. Prevalence of osteopenia (z AD-SoS values <-2 SD) was higher in patients with T1DM and CD and poor compliance to the diet (45.5%) compared with patients with T1DM (8%) or patients with both diseases strictly compliant to diet (12.9%) (p=0.015). A negative correlation between Ad-SoS z score and HbA1c (r -0.236, p=0.036) was found when patients with T1DM and patients with T1DM and CD, who strictly adhere to the diet, were pooled. In conclusion the quality of bone as assessed by phalangeal ultrasound in patients with T1DM and CD, who strictly adhere to gluten free diet, is similar to that found in T1DM patients. A higher prevalence of osteopenia is present in patients with both diseases who reported habitual transgressions to gluten free diet. The gluten free diet, as well as the optimization of glycemic control, plays an important role in preventing the osteopenic status caused by the clustering of these two chronic diseases.

Phalangeal quantitative ultrasound in children with phenylketonuria: a pilot study

Bone alterations in phenylketonuria (PKU) have been detected, especially with increasing age, in several studies by using different radiologic techniques. Quantitative ultrasound (QUS) assesses skeletal status by measuring the amplitude-dependent speed of sound (AD-SoS) and the bone transmission time (BTT), mainly dependent on mineral density and cortical thickness. Bone condition in 30 children and adolescents (mean age 15.1 +/- 6.4 y) affected by PKU was evaluated by phalangeal QUS, considering its relationship with their clinical, biochemical and therapeutic features. Measured AD-SoS Z-Score and BTT Z-Score were 0.27 +/- 1.42 and -0.26 +/- 1.21, respectively. In patients with previous fractures, the two QUS parameters were lower than in patients without history of fracture (p < 0.001 and p = 0.006, respectively). AD-SoS Z-Score and BTT Z-Score were negatively correlated with plasma phenylalanine (Phe) concentration in the year before QUS (p = 0.005 and p < 0.001, respectively) and with age (p < 0.001 for both parameters). These results parallel the previous findings obtained by different radiologic tools and suggest phalangeal QUS as an attractive option for the regular evaluation and longitudinal monitoring of bone condition in children and adolescents affected by PKU.