Quantitative bone US measurements in neonates and their mothers

Recent advancements in the analysis of bone microstructure: New dimensions in forensic anthropology

Bone is a mechanically active, three-dimensionally (3D) complex, and dynamic tissue that changes in structure over the human lifespan. Bone tissue exists and remodels in 3D and changes over time, introducing a fourth dimension. The products of the remodelling process, secondary and fragmentary osteons, have been studied substantially using traditional two-dimensional (2D) techniques. As a result, much has been learned regarding the biological information encrypted in the histomorphology of bone, yielding a wealth of information relating to skeletal structure and function. Three-dimensional imaging modalities, however, hold the potential to provide a much more comprehensive understanding of bone microarchitecture. The visualization and analysis of bone using high-resolution 3D imaging will improve current understandings of bone biology and have numerous applications in both biological anthropology and biomedicine. Through recent technological advancements, we can hone current anthropological applications of the analysis of bone microstructure and accelerate research into the third and fourth dimensional realms. This review will explore the methodological approaches used historically by anthropologists to assess cortical bone microstructure, spanning from histology to current ex vivo imaging modalities, discuss the growing capabilities of in vivo imaging, and conclude with an introduction of novel non-histological modalities for investigating bone quality.

Quantitative Ultrasound (QUS) in the Management of Osteoporosis and Assessment of Fracture Risk

The use of quantitative ultrasound (QUS) for a variety of skeletal sites, associated with the absence of technology-specific guidelines, has created uncertainty with respect to the application of QUS results to the management of individual patients in clinical practice. However, when prospectively validated (this is not the case for all QUS devices and skeletal sites), QUS is a proven, low-cost, and readily accessible alternative to dual-energy X-ray absorptiometry (DXA) measurements of bone mineral density (BMD) for the assessment of fracture risk. Indeed, the clinical use of QUS to identify subjects at low or high risk of osteoporotic fracture should be considered when central DXA is unavailable. Furthermore, the use of QUS in conjunction with clinical risk factors (CRF),allows for the identification of subjects who have a low and high probability of osteoporotic fracture. Device- and parameter-specific thresholds should be developed and cross-validated to confirm the concurrent use of QUS and CRF for the institution of pharmacological therapy and monitoring therapy.

Postnatal Changes in Tibial Bone Speed of Sound of Preterm and Term Infants during Infancy

This study aimed to evaluate changes in tibial bone speed of sound (SOS) over time, in preterm and term infants during infancy, in addition to identifying factors influencing the development of tibial SOS during infancy. Preterm (n = 155) and term (n = 65) infants were enrolled in this study. Tibial bone SOS was measured using quantitative ultrasonography (QUS) on the left tibia of newborn infants after birth (within 7 days), at 1 month old, and then every 2 months until subjects were approximately 12-15 months old. Follow-up checks included anthropometric measurements and tibial bone SOS. Mean tibial bone SOS at birth was significantly higher in term infants (mean ± SD, 2968.5 ± 99.7 m/s) than in preterm infants (2912.2 ± 122.6 m/s). Values of follow-up tibial bone SOS declined for the first 4 months, and then increased gradually until 12-15 months old. This increasing trend was greater in preterm infants after 2 months of corrected age than in term infants. There were no significant differences by 12-15 months of age between preterm and term infants. A longitudinal mixed-effect model controlling for internal correlations and other covariates in the two groups showed that age and the SOS value at birth were important factors affecting the tibial bone SOS in both preterm and term newborn infants during infancy. There are significant differences in the pattern of change in tibial bone SOS values between preterm and term infants during the first 12-15 months of life. Age and SOS value at birth were important factors affecting the pattern of tibial bone SOS change in both preterm and term newborn infants during infancy.

Bone measurements of infants with hyperbilirubinemia by quantitative ultrasound: the influence of phototherapy

OBJECTIVE

The purpose of the current study was to investigate the possible effects of phototherapy on bone status of term infants evaluated by measurement of tibial bone speed of sound (SOS).

MATERIALS AND METHODS

The phototherapy group (n = 30) consisted of children who had undergone phototherapy for at least 24 h and the control group (n = 30) comprised children who had not received phototherapy. Blood samples were obtained from all infants for serum calcium, phosphorus, magnesium, alkaline phosphatase, parathyroid hormone and vitamin D concentrations. The left tibial quantitative ultrasound (QUS) measurements were performed using a commercial device.

RESULTS

There was no statistically significant difference between phototherapy-exposed and nonexposed infants in terms of Ca, P, ALP, PTH and vitamin D levels. Comparison of bone SOS between the phototherapy-exposed and control group revealed no statistically difference. Also, no significant difference in Z-score for SOS was observed between those with or without exposure.

CONCLUSION

The data of our study indicate that phototherapy treatment has no impact on bone status in the hyperbilirubinemic infants. Although there is no statistically significant evidence of an excess risk of bone damage following phototherapy, studies with larger sample sizes and longer duration of follow-up are needed to gain a better understanding of its effects.

Bone densitometry in infants and young children: the 2013 ISCD Pediatric Official Positions

Infants and children <5 yr were not included in the 2007 International Society for Clinical Densitometry Official Positions regarding Skeletal Health Assessment of Children and Adolescents. To advance clinical care of very young children, the International Society for Clinical Densitometry 2013 Position Development Conference reviewed the literature addressing appropriate methods and skeletal sites for clinical dual-energy X-ray absorptiometry (DXA) measurements in infants and young children and how results should be reported. DXA whole-body bone mineral content and bone mineral density for children ≥3 yr and DXA lumbar spine measurements for infants and young children 0-5 yr were identified as feasible and reproducible. There was insufficient information regarding methodology, reproducibility, and reference data to recommended forearm and femur measurements at this time. Appropriate methods to account for growth delay when interpreting DXA results for children <5 yr are currently unknown. Reference data for children 0-5 yr at multiple skeletal sites are insufficient and are needed to enable interpretation of DXA measurements. Given the current scarcity of evidence in many areas, it is likely that these positions will change over time as new data become available.

Bone status and associated factors measured by quantitative ultrasound in preterm and full-term newborn infants

BACKGROUND

A clear understanding of the factors associated with bone status in newborn infants is essential for devising strategies for preventing osteoporotic fracture in future generations.

OBJECTIVE

The aims of this study were to perform bone speed of sound (SOS) to assess the status of the tibia in preterm and full-term newborns, and to evaluate factors associated with bone status at birth.

STUDY DESIGNS

Bone SOS was measured by quantitative ultrasonography on the left tibia in full-term and preterm newborn infants immediately after birth. A birth chart and maternal history were recorded. Univariate and multivariate analyses were performed to identify factors affecting bone SOS at birth.

SUBJECTS

The study analyzed 667 infants, including 370 males and 297 females, during study period.

RESULTS

Univariate analysis revealed that gender, gestational age (GA) and birth anthropometrics significantly affected tibial bone SOS at birth whereas maternal factors did not. Multivariate multiple regression analysis revealed that gender (male-to-female coefficient of 45.71 and 32.52 in premature and full-term infants, respectively), GA (coefficient of 32.55 and 31.27 in premature and full-term infants, respectively, for every 1-week increase), and birth weight (coefficient of -0.11 and -0.103 in premature and full-term infants, respectively, for every 1-gram increase) were important factors affecting tibial bone SOS in both preterm and full-term newborn infants at birth.

CONCLUSIONS

Male gender and advanced GA have a positive effect on increasing tibial bone SOS at birth, while birth weight had a negative effect on increasing tibial bone SOS. Tibial bone SOS is higher in small-for-gestational-age infants than in those of appropriate-for-gestational-age infants.

Longitudinal changes of bone ultrasound measurements in healthy infants during the first year of life: influence of gender and type of feeding

There is evidence suggesting that early events in life may predispose the adult to osteoporosis. We assessed bone status by quantitative ultrasonography in healthy neonates, and we report the changes occurring during the first year of life, according to the type of early feeding. We measured the speed of sound (SOS) of the left tibia in 116 full-term infants (0-9 days of age) and in their mothers (21-42 years of age). SOS values did not correlate with gestational age of the study subjects (r = 0.08) or anthropometric measurements. The SOS measurements of the mothers did not correlate with those of their children (r = 0.01). Fifty-seven infants had SOS measurements performed at 4 and 12 months. Twenty-five infants were exclusively breast-fed, 12 received formula milk from birth, and 20 received human and formula milk. SOS measurements at 4 months were comparable with those at baseline, whereas at 12 months they were significantly higher. No effect of type of feeding was observed, indicating that SOS changes may be independent of the type of early diet.

Bone ultrasound velocity in neonates with intrauterine growth deficit reflects a growth continuum

Both bone mass by densitometry and speed of sound (SOS) from quantitative ultrasound of the bone (QUS) are directly related to bone strength. However, reports of lower bone mass but higher SOS in neonates with intrauterine growth deficit lead to apparent contradictory conclusions on bone strength. Three groups of infants were studied: small for gestation (SGA) with birth weights ≤10th percentile for gestation and 2 control groups with appropriate birth weights (11th to 90th percentile) for gestation (AGA): matched to SGA group for gestation and birth weight, respectively. SOS was measured with a commercial QUS instrument (Sunlight Omnisense 7000, Sunlight Medical Ltd, Tel Aviv, Israel) and 2 manufacturer supplied ultrasound probes (CS and CR) for small bones. The SGA group had significantly (p<0.01) higher SOS compared with weight matched but gestational less matured control group by an average of 54m/s with the CS probe and 80m/s with the CR probe but not significantly different from gestation-matched AGA group. SOS values from both probes were significantly correlated (r=0.71-0.91) but were significantly different between probes. Probe failure occurred with both probes. We conclude that QUS SOS values in SGA neonates are a reflection of a continuum of intrauterine maturation of the skeleton.

Reduced tibial speed of sound in Chinese infants at birth compared with Caucasian peers: the effects of race, gender, and vitamin D on fetal bone development

SUMMARY

This study compared bone status between Chinese and Caucasian infants at birth, showing that Chinese neonates have lower tibial speed of sound, which is influenced by gender, gestational age, season of birth, and maternal vitamin D status. The effects of these factors on fetal bone development were discussed.

INTRODUCTION

We compared the differences of speed of sound (SOS) accessed by quantitative ultrasound between Chinese and Caucasian infants at birth and explored the relationship between the concentrations of serum 25-hydroxyvitamin D [25(OH)D] and bone SOS in maternal-infant pairs.

METHODS

SOS for the tibial bone was measured at birth in 267 Chinese infants. We used the Z-scores for the direct comparisons which were available from the instrument based data of gender and age-matched Caucasian peers. The concentrations of serum 25(OH)D and bone SOS in 32 maternal-infant pairs were measured at birth in winters.

RESULTS

the Chinese infants had lower SOS demonstrated by the Z-scores. Significant differences of SOS and Z-scores were found between genders, gestational ages, birth weight, and seasons of birth. The differences of Z-scores negatively decreased with gestational age, suggesting that the bone status of Chinese infants lags behind that of the Caucasian infants during the last trimester of pregnancy in utero. The tibial SOS of infants born in winters was 2.0% higher than those born in summers after adjustment. The infant SOS correlated with maternal serum 25(OH)D (r = 0.399, P = 0.024) and infant serum 25(OH)D (r = 0.394, P = 0.026).

CONCLUSIONS

Chinese neonates have lower SOS which is influenced by gender, gestational age, season of birth, and maternal vitamin D status. It is inferred that, in pace with gestational age, race and gender effects on fetal bone development are modified by materno-fetal vitamin D status.

Effect of subcutaneous fat on quantitative bone ultrasound in chicken and neonates

Bone quantitative ultrasound generated speed of sound (SOS) is a marker of bone strength. However, critical evaluation of its validity for use in small bones is extremely limited, and SOS data may not be consistent with data obtained from dual energy x ray absorptiometry, another marker of bone strength. We report the SOS values pre and postinjection of s.c. fat using a chicken bone model; and in large for gestation and appropriate for gestation neonates to determine the influence of s.c. fat. Average SOS were lowered for the chicken bones postfat injection by 36 m/s (CS probe) and 58 m/s (CR probe), and in large for gestation group by 75 m/s (CS probe) and 51 m/s (CR probe) (p = 0.03-0.004 paired t test) although SOS measurements from each probe are significantly correlated within the large (r = 0.78) and appropriate (r = 0.83) for gestation group. Failed SOS measurements occurred significantly more frequently in the postinjection studies regardless of the probe used in the chicken bone model and for the CS probe in large for gestation neonates. The lowered bone quantitative ultrasound measurements in large for gestation neonates is likely a measurement artifact from increased s.c. fat.