Bone turnover markers and bone strength during the first weeks of life in very low birth weight premature infants

Critical review of the evidence for Vojta Therapy: a systematic review and meta-analysis

Introduction

It is essential to link the theoretical framework of any neurophysiotherapy approach with a detailed analysis of the central motor control mechanisms that influence motor behavior. Vojta therapy (VT) falls within interventions aiming to modify neuronal activity. Although it is often mistakenly perceived as exclusively pediatric, its utility spans various functional disorders by acting on central pattern modulation. This study aims to review the existing evidence on the effectiveness of VT across a wide range of conditions, both in the adult population and in pediatrics, and analyze common therapeutic mechanisms, focusing on motor control modulation.

Aim

The goals of this systematic review are to delineate the existing body of evidence concerning the efficacy of Vojta therapy (VT) in treating a broad range of conditions, as well as understand the common therapeutic mechanisms underlying VT with a specific focus on the neuromodulation of motor control parameters.

Methods

PubMed, Cochrane Library, SCOPUS, Web of Science, and Embase databases were searched for eligible studies. The methodological quality of the studies was assessed using the PEDro list and the Risk-Of-Bias Tool to assess the risk of bias in randomized trials. Methodological quality was evaluated using the Risk-Of-Bias Tool for randomized trials. Random-effects meta-analyses with 95% CI were used to quantify the change scores between the VT and control groups. The certainty of our findings (the closeness of the estimated effect to the true effect) was evaluated using the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE).

Results

Fifty-five studies were included in the qualitative analysis and 18 in the meta-analysis. Significant differences in cortical activity (p = 0.0001) and muscle activity (p = 0.001) were observed in adults undergoing VT compared to the control, as well as in balance in those living with multiple sclerosis (p < 0.03). Non-significant differences were found in the meta-analysis when evaluating gross motor function, oxygen saturation, respiratory rate, height, and head circumference in pediatrics.

Conclusion

Although current evidence supporting VT is limited in quality, there are indications suggesting its potential usefulness for the treatment of respiratory, neurological, and orthopedic pathology. This systematic review and meta-analysis show the robustness of the neurophysiological mechanisms of VT, and that it could be an effective tool for the treatment of balance in adult neurological pathology. Neuromodulation of motor control areas has been confirmed by research focusing on the neurophysiological mechanisms underlying the therapeutic efficacy of VT.Systematic Review Registration:https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=476848, CRD42023476848.

Effect of physical therapy on bone remodelling in preterm infants: a multicenter randomized controlled clinical trial

Background

Preterm infants have a low level of bone mineralization compared to those born at term, since 80% of calcium incorporation occurs at the end of pregnancy. The purpose of the present study was to investigate the effect of reflex locomotion therapy on bone modeling and growth in preterm infants and to compare its effect with those of other Physiotherapy modalities.

Methods

A multicentre randomized controlled clinical trial was conducted (02/2016 – 07/2020). 106 preterm infants born at the Virgen de la Arrixaca University Clinical Hospital, the General University Hospital of Elche and the Torrecárdenas University Hospital of Almería, between 26 and 34 weeks with hemodynamic stability, complete enteral nutrition and without any metabolic, congenital, genetic, neurological or respiratory disorders were evaluated for inclusion. Infants were randomly assigned to three groups: one group received reflex locomotion therapy (EGrlt); another group received passive mobilizations with gentle joint compression (EGpmc); and the control group received massage (CG). All treatments were carried out in the neonatal units lasting one month. The main outcome measure was bone formation and resorption measured with bone biomarkers. A mixed ANOVA was used to compare the results of bone biomarkers, and anthropometric measurements.

Results

Infants were randomized to EGrlt (n = 38), EGpmc (n = 32), and CG (n = 36). All groups were similar in terms of gender (p = 0.891 female 47.2%), gestational age (M = 30.753, SD = 1.878, p = 0.39) and birth weight (M = 1413.45, SD = 347.36, p = 0.157). At the end of the study, significant differences were found between the groups in their interaction in bone formation, measured with osteocalcin [F (2,35) = 4.92, p = 0.013, η_p² = 0.043], in benefit of the EGrlt.

Conclusions

Reflex locomotion therapy has been effective in improving bone formation, more so than other Physiotherapy modalities. Therefore, reflex locomotion therapy could be considered one of the most effective physiotherapeutic modalities for the prevention and treatment of osteopenia of prematurity.

Trial registrstion

Trial retrospectively registered at ClinicalTrials.gov. First posted on 22/04/2020. Registration number: NCT04356807.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12887-022-03402-2.

The first step in an investigation of quantitative ultrasound as a technique for evaluating infant bone strength

This study's purpose is to evaluate whether bone speed of sound (SOS) data, a parameter of quantitative ultrasound, collected from an infant autopsy sample are comparable to data collected from healthy, living infants. We hypothesize that SOS values obtained from deceased term-born infants will fall within the normal range for healthy, living infants. The study sample consists of 351 deceased infants between the ages of 30 weeks gestation at birth to 1 year postnatal at the time of death receiving autopsies at the Harris County Institute of Forensic Sciences or Texas Children's Hospital in Houston, TX. Various multivariate and univariate statistics were used to examine the relationship between SOS and age, prematurity, and chronic illness. The results of an ANOVA comparing the study sample data to published data from healthy, living infants indicate the SOS data are comparable. Additionally, a MANOVA indicated significant differences in SOS related to prematurity (p = 0.001) and age (p < 0.001). Mean SOS was significantly greater among term-born infants (M = 3065.66, SD =165.05) than premature infants (M = 2969.71, SD =192.72). Age had a significant polynomial (cubic) relationship with SOS for both the premature and term groups (p < 0.001). Results suggest that bone from an infant autopsy sample is an appropriate surrogate to examine the relationship between SOS and determinants of bone strength. Therefore, future research will use this study sample to investigate the relationship between SOS and determinants of bone strength in infants.

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.

The Clinical and Biochemical Predictors of Bone Mass in Preterm Infants

BACKGROUND

Metabolic bone disease of prematurity still occurs in preterm infants, although a significant improvement in neonatal care has been observed in recent decades. Dual-energy X-ray absorptiometry (DXA) is the precise technique for assessing bone mineral content (BMC) in preterm infants, but is not widely available.

AIM

To investigate the clinical and biochemical parameters, including bone metabolism markers as potential predictors of BMC, in preterm infants up to 3 months corrected age (CA).

MATERIALS AND METHODS

Ca-P homeostasis, iPTH, 25-hydroxyvitamin D, osteocalcin, N-terminal propeptide, cross-linked C-telopeptide and amino-terminal pro C-type natriuretic peptide and the DXA scans were prospectively performed in 184 preterm infants (≤ 34 weeks' gestation) between term age and 3 mo CA. Lower bone mass was defined as BMC below or equal to respective median value for the whole study group, rounded to the nearest whole number.

RESULTS

The appropriate quality DXA scans were available for 160 infants (87%) examined at term and for 130 (71%) tested at 3 mo CA. Higher iPTH level was the only independent predictor of lower BMC at term, whereas lower BMC at 3 mo CA was associated both with lower urinary phosphate excretion and higher serum osteocalcin level. ROC analysis showed that iPTH >43.6 pg/mL provided 40% sensitivity and 88% specificity in identification of preterm infants with lower BMC at term. In turn, urinary phosphate excretion (TRP>97% or UP/Cr ≤0.74 mg/mg) and serum osteocalcin >172 ng/mL provided 40% sensitivity and 93% specificity in identification of infants with decreased BMC at 3 mo CA.

CONCLUSION

Serum iPTH might to be a simple predictor of reduced BMC in preterm infants at term age, but urinary phosphate excretion and serum osteocalcin might predict reduced BMC at 3 mo CA. These results represent a promising diagnostic tool based on simple, widely available biochemical measurements for bone mass assessment in preterm infants.

The Effect of Assisted Exercise Frequency on Bone Strength in Very Low Birth Weight Preterm Infants: A Randomized Control Trial

We aimed to assess whether a twice daily assisted exercise interventional program will have a greater effect on bone strength compared to a once daily intervention or no intervention in very low birth weight (VLBW) preterm infants. Thirty-four very VLBW preterm infants (mean BW 1217 ± 55 g and mean gestational age 28.6 ± 1.1 weeks) were randomly assigned into one of three study groups: twice daily interventions (n = 13), a once daily intervention (n = 11), and no intervention (control, n = 10). The intervention was initiated at a mean of 8 ± 2.4 days of life and continued for 4 weeks. It included passive extension and flexion range-of-motion exercise of the upper and lower extremities. Bone strength was measured at enrollment and after 2 and 4 weeks using quantitative ultrasound of tibial bone speed of sound (SOS, Sunlight Omnisense™). At enrollment, the mean bone SOS was comparable between the twice daily interventions, once daily intervention and control groups (2918 ± 78, 2943 ± 119, and 2910 ± 48 m/s, respectively). As expected, the bone SOS declined in all groups during the study period (-23.6 ± 24, -68.8 ± 28, and -115.8 ± 30 m/s, respectively, p < 0.05), with a significantly attenuated decrease in bone strength in the twice daily intervention group (p = 0.03). A twice daily intervention program of assisted range-of-motion exercise attenuates the decrease in bone strength and may decrease the risk of osteopenia and future fractures in VLBW preterm infants.

Metabolic bone disease in the preterm infant: Current state and future directions

Neonatal osteopenia is an important area of interest for neonatologists due to continuing increased survival of preterm infants. It can occur in high-risk infants such as preterm infants, infants on long-term diuretics or corticosteroids, and those with neuromuscular disorders. Complications such as rickets, pathological fractures, impaired respiratory function and poor growth in childhood can develop and may be the first clinical evidence of the condition. It is important for neonatologists managing such high-risk patients to regularly monitor biochemical markers for evidence of abnormal bone turnover and inadequate mineral intake in order to detect the early phases of impaired bone mineralization. Dual-energy X-ray absorptiometry has become an increasingly used research tool for assessing bone mineral density in children and neonates, but more studies are still needed before it can be used as a useful clinical tool. Prevention and early detection of osteopenia are key to the successful management of this condition and oral phosphate supplements should be started as soon as is feasible.

Growth and bone mineralization in small-for-gestational-age preterm infants

BACKGROUND

Preterm infants are at risk for metabolic bone disease and suboptimal growth. This study examined the hypothesis that, apart from prematurity, intrauterine growth status (expressed as gestational age-specific birthweight standard deviation score) influences bone mineralization and body composition in early infancy.

METHODS

In this retrospective study, the groups consisted of preterm small-for-gestational-age (SGA) infants (n = 18; SGA group) and preterm appropriate-for-gestational-age (AGA) infants (n = 24; AGA group). Postnatal bone mineralization was measured at term-adjusted age (postmenstrual age, 37-42 weeks). Bone mineral content (BMC) and body composition were determined on dual-energy X-ray absorptiometry of the whole body.

RESULTS

BMC and lean mass were significantly lower in the SGA group than in the AGA group at term-adjusted age (37-42 weeks postmenstrual age). Stepwise regression analysis identified weight at examination as the most significant factor, accounting for 51% of the variance in BMC.

CONCLUSION

Bodyweight at term-adjusted age, rather than intrauterine growth, may affect postnatal bone mineralization in preterm low-birthweight infants. Therefore, promoting an increase in body size might increase postnatal bone mineralization in preterm SGA infants.

Feasibility of a caregiver-assisted exercise program for preterm infants

Mounting evidence shows that low-birth-weight and prematurity are related to serious health problems in adulthood, including increased body fat, decreased fitness, poor bone mineralization, pulmonary problems, and cardiovascular disease. There are data to suggest that increasing physical activity in preterm infants will have effects on short-term muscle mass and fat mass, but we also hypothesized that increasing physical activity early in life can lead to improved health outcomes in adulthood. Because few studies have addressed the augmentation of physical activity in premature babies, the objective of this study was to evaluate the feasibility of whether caregivers (mostly mothers) can learn from nurses and other healthcare providers to implement a program of assisted infant exercise following discharge. Ten caregivers of preterm infants were taught by nurses, along with occupational therapists and other healthcare providers, to perform assisted infant exercise and instructed to conduct the exercises daily for approximately 3 weeks. The researchers made home visits and conducted qualitative interviews to understand the caregivers' experiences with this exercise protocol. Quantitative data included a caregiver's daily log of the exercises completed to measure adherence as well as videotaped caregiver sessions, which were used to record errors as a measure of proficiency in the exercise technique. On average, the caregivers completed a daily log on 92% of the days enrolled in the study and reported performing the exercises on 93% of the days recorded. Caregivers made an average of 1.8 errors on 2 tests (with a maximum of 23 or 35 items on each, respectively) when demonstrating proficiency in the exercise techniques. All caregivers described the exercises as beneficial for their infants, and many reported that these interventions fostered increased bonding with their babies. Nearly all reported feeling "scared" of hurting their babies during the first few days of home exercise but stated that fears were alleviated by practice in the home and further teaching and learning. Caregivers were willing and able to do the exercises correctly, and they expressed a belief that the intervention had positive effects on their babies and on caregiver-infant interactions. These findings have important implications for nursing practice because nurses are in key positions to teach and encourage caregivers to practice these exercises with their newborn babies.

The validity of biochemical markers in metabolic bone disease in preterm infants: a systematic review

To establish the validity of biochemical markers of metabolic bone disease (MBD) in preterm infants.

CONCLUSION

There is insufficient evidence that any of the frequently used serum measurements are valid biochemical markers of MBD in preterm infants. Increased urinary calcium concentration may be a valid biochemical marker, but more research is necessary to confirm this.

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.

Serial measurements of serum alkaline phosphatase for early prediction of osteopaenia in preterm infants

AIM

Osteopaenia commonly occurs in preterm infants; however, its diagnosis is often delayed when based on radiological findings. The aim of this study was to examine whether serial measurements of bone turnover markers are useful for early prediction of osteopaenia in preterm infants.

METHODS

Premature infants of ≤ 34 weeks gestation were enrolled. Serum alkaline phosphatase (ALP), bone form ALP (BALP), calcium and inorganic phosphate were concurrently measured biweekly from 3 weeks post-natal age until 40 weeks post-conceptional age. Radiographic examination of the forearm was performed at term age. Osteopaenia was defined as positive radiographic findings according to Koo's criteria.

RESULTS

Of the 46 premature infants completing the follow-up study at term age, 18 showed osteopaenia in radiographic examination. Serum ALP was highly correlated with BALP (R(2) = 0.93, P < 0.001). Infants who had osteopaenia showed a higher level of ALP and BALP after 3 weeks post-natal age than those who had no osteopaenia. ALP concentration exceeding 700 IU/L at 3 weeks post-natal age was predictive of osteopaenia at term age (sensitivity 73% and specificity 73%) and so did for the predictive value of BALP concentration exceeding 95 ug/L (sensitivity 73% and specificity 80%). BALP measures provided no greater benefit of diagnostic performance than ALP in early detection of osteopaenia. Furthermore, premature infants with osteopaenia showed similar levels of calcium and inorganic phosphatase concentration compared with those without.

CONCLUSION

Serum ALP concentration exceeding 700 IU/L at 3 weeks post-natal age can predict the risk of osteopaenia in preterm infants.

Fisioterapia motora no tratamento do prematuro com doença metabólica óssea

OBJETIVO: Revisar o papel da fisioterapia motora no prematuro com risco de desenvolver doença metabólica óssea. FONTES DE DADOS: Trata-se de uma revisão de literatura publicada entre 1986 e 2009, utilizando as seguintes palavras-chave: prematuro, calcificação fisiológica, modalidades de fisioterapia, doenças ósseas metabólicas e os respectivos descritores no idioma inglês. Foram selecionados 29 artigos científicos, via PubMed e ISI Web, além de um capítulo de livro nacional. SÍNTESE DOS DADOS: As doenças ósseas metabólicas compreendem um conjunto de condições relacionadas a alterações no processo de calcificação fisiológica, levando desde à fragilidade estrutural até ao desenvolvimento de fraturas. A aplicação rotineira de exercícios de mobilização passiva articular, massagem e posicionamento está relacionada ao ganho ponderal, ao aumento na densidade e no conteúdo mineral ósseo. CONCLUSÕES: A implementação de exercícios de fisioterapia motora parece proporcionar estabilidade ou estímulo para a formação óssea, podendo, consequentemente, prevenir e/ou minimizar as complicações decorrentes da doença metabólica óssea.

Early high calcium and phosphorus intake by parenteral nutrition prevents short-term bone strength decline in preterm infants

BACKGROUND AND AIM

Very premature newborns have an increased risk of low bone mass and metabolic bone disease. Most longitudinal studies report a significant decline in bone strength in the first weeks after birth. The aim of the study was to evaluate whether higher early calcium (Ca) and phosphorus (P) intake delivered by parenteral nutrition (PN) can prevent bone strength decline in preterm infants, within the first weeks after birth.

PATIENTS AND METHODS

This was a randomized controlled trial of consecutively admitted neonates born with ≤ 33 weeks of gestational age, assigned to receive either Ca 45 mg · kg⁻¹ · day⁻¹ (low dose [LD]) or Ca 75 mg · kg⁻¹ · day⁻¹ (high dose [HD]) by PN. P was added to the PN solutions at a fixed Ca:P ratio (mg) of 1.7:1. Bone strength was assessed by the speed of sound (SOS) using the quantitative ultrasound method. Measurements were performed weekly from birth until discharge. Low bone strength (SOS < 10th centile of reference values) was the main outcome.

RESULTS

Eighty-six infants were enrolled, 40 assigned to LD group and 46 to HD group. Mean (standard error) gestational age was 29.6 weeks (2.1) and birth weight was 1262 g (0.356). In the HD group, the SOS values never fell below those recorded at birth and, up to the sixth week of life, low bone strength was significantly less frequent as compared with that in the LD group, in spite of progressive reduction in parenteral mineral intake and/or establishment of full enteral feeding.

CONCLUSIONS

Early assigned parenteral intake of Ca 75 mg · kg⁻¹ · day⁻¹ and P 44 mg · kg⁻¹ · day⁻¹ significantly contributed to preventing short-term bone strength decline in preterm infants.

Growth factors, inflammatory cytokines and postnatal bone strength in preterm infants

AIM

To assess the relationships between growth factors, inflammatory cytokines and postnatal bone development in preterm infants.

METHODS

Fifty premature infants (24-32 weeks gestational age, mean birth weight: 1,024 +/- 50 g) participated in the study. Bone strength was determined weekly by quantitative ultrasound measurements of bone speed of sound (SOS). Blood serum measurements of growth factors included circulating IGF-I and GH binding protein. Measurements of circulating cytokines included the pro-inflammatory mediator interleukin (IL)-6, and the anti-inflammatory mediator IL-1 receptor antagonist. Samples were collected when the preterm infants were stabilized and prior to discharge.

RESULTS

Despite a significant increase in body weight (from 1,024 +/- 50 to 2,420 +/- 59 g, p < 0.001) and body length (from 35.4 +/- 0.6 to 44.6 +/- 0.4 cm, p < 0.001) there was a significant decrease in bone SOS during the follow-up period. There was a significant increase in growth factors and a decrease in inflammatory cytokines during the follow-up. Participants were divided into preterm infants who increased bone SOS (bone gainers, n = 16, from 2,867 +/- 38 to 2,910 +/- 41 m/sec), or decreased bone SOS (bone losers, n = 34, from 2,967 +/- 33 to 2,818 +/- 28 m/sec) during follow-up. Baseline bone SOS was significantly lower in the bone gainers. Baseline circulating growth factors were higher and inflammatory cytokines lower in the bone gainers; however, only the difference in IL-6 reached statistical significance (6.4 +/- 1.6 versus 10.5 +/- 1.2 pg/ml, in bone gainers and losers, respectively; p < 0.05).

CONCLUSIONS

Preterm infants with lower bone SOS at birth tend to 'catch-up' during early postnatal weeks. Increases in bone strength in preterm infants were associated with reduced inflammatory state as suggested by lower levels of circulating IL-6.

High frequencies of elevated alkaline phosphatase activity and rickets exist in extremely low birth weight infants despite current nutritional support

Background

Osteopenia and rickets are common among extremely low birth weight infants (ELBW, <1000 g birth weight) despite current practices of vitamin and mineral supplementation. Few data are available evaluating the usual course of markers of mineral status in this population. Our objectives in this study were to determine the relationship between birth weight (BW) and peak serum alkaline phosphatase activity (P-APA) in ELBW infants and evaluate our experience with the diagnosis of rickets in these infants.

Methods

We evaluated all ELBW infants admitted to Texas Children's Hospital NICU in 2006 and 2007. Of 211 admissions, we excluded 98 patients who were admitted at >30 days of age or did not survive/stay for >6 weeks. Bone radiographs obtained in 32 infants were reviewed by a radiologist masked to laboratory values.

Results

In this cohort of 113 infants, P-APA was found to have a significant inverse relationship with BW, gestational age and serum phosphorus. In paired comparisons, P-APA of infants <600 g (957 ± 346 IU/L, n = 20) and infants 600–800 g (808 ± 323 IU/L, n = 43) were both significantly higher than P-APA of infants 800–1000 g (615 ± 252 IU/L, n = 50), p < 0.01. Thirty-two patients had radiographic evaluation for evidence of rickets, based on P-APA greater than 800 IU/L, parenteral nutrition greater than 3 to 4 weeks, or clinical suspicion. Of these, 18 showed radiologic rickets and 14 showed osteopenia without rickets. Infants with BW <600 g were more likely to have radiologic rickets (10/20 infants) compared to those with BW 600–800 g (6/43 infants) and BW 800–1000 g (2/50 infants), p < 0.01 for each. P-APA was not significantly higher in infants with radiologic rickets (1078 ± 356 IU/L) compared to those without radiologic evidence of rickets (943 ± 346, p = 0.18).

Conclusion

Elevation of P-APA >600 IU/L was very common in ELBW infants. BW was significantly inversely related to both P-APA and radiologic rickets. No single value of P-APA was related to radiological findings of rickets. Given the very high risk of osteopenia and rickets among ELBW infants, we recommend consideration of early screening and early mineral supplementation, especially among infants <600 g BW.

Effects of motor physical therapy on bone mineralization in premature infants: a randomized controlled study

OBJECTIVE

To study the effect of physical therapy on bone mineralization, weight gain and growth in preterm infants.

METHOD

After fulfilling the inclusion criteria, preterm infants were matched for gestational age and birth weight and then randomly assigned to the physiotherapy group (PG, n=15) and control group (CG, n=14). The PG received motor physical therapy for 15 min daily, 5 times per week until hospital discharge. Bone mineralization was measured by total body dual energy X-ray beam absorptiometry (DEXA) at the onset and end of the study. Statistical analysis was realized by ANCOVA and linear correlation tests.

RESULT

The physical therapy group (PG) presented greater body weight gain per day (27.4+/-2.4 vs 21.01+/-4.4 g, P<0.001) and length (1.3+/-0.3 vs 0.8+/-0.2 cm week(-1), P<0.001) than did the control group (CG). Body composition values verified by DEXA were greater for the PG. The mean gain in bone mineral content (BMC) (mg) was greater in the PG (434+/-247.5 vs -8.9+/-11.4, P<0.001), as was the mean bone mineral density (BMD) gain (mg cm(-2)) (8.4+/-5.6 vs -3.1+/-5.5, P<0.001). The gain in bone area (BA,cm(2)) was 10.3+/-5 in the PG vs 1.5 +/-2 in the CG (P<0.001). The gain in lean mass (LM) (g) in the PG was also greater than in the CG (271.1+/-21.4 vs 109.1+/-1.0, P<0.009). The fat mass (g) was similar between the groups (P=0.432).

CONCLUSION

These results showed that physiotherapy in preterm infants produced greater gains in growth, body weight, BMC, BMD, BA and LM.

Osteopenia of prematurity: a national survey and review of practice

Premature infants are at significant risk of reduced bone mineral content (BMC) and subsequent osteopenia. There are currently no standard practices regarding screening, investigation or treatment of this condition. We present a case report and findings of a national survey of 36 level 2 and 3 neonatal units (72% response rate). The findings showed widely disparate practice regarding screening, prevention and treatment. We summarize the tests currently available for osteopenia and suggest guidelines for management of the at risk group.

CONCLUSION

Our survey confirms inconsistent practices regarding management of infants at risk of osteopenia of prematurity. Investigations and treatments available are summarized together with a guideline for management of this susceptible group of infants.

Enriched post-discharge formula versus term formula for bone strength in very low birth weight infants: a longitudinal pilot study

AIM

To initiate a longitudinal pilot study comparing the effect of nutrient-enriched post-discharge formula (PDF) with standard term formula (TF) on bone strength of very low birth weight (VLBW) infants in the first six months post-term.

METHODS

Two matched groups of VLBW infants were randomly assigned to enriched PDF (n=10) or TF (n=10) at corrected age of 40 weeks. Anthropometric measurements of growth and measurements of bone speed of sound (SOS) indicating bone strength and bone turnover markers (bone-specific alkaline phosphatase and cross-linked carboxy terminal telopeptide of type I collagen) were taken at term and at three and six months corrected age.

RESULTS

The anthropometric measurements of infants fed PDF and TF were comparable at three and six months corrected age. Bone SOS of the PDF group increased from 2760+/-113 m/s at term to 2877+/-90 m/s and 3032+/-60 m/s at three and six months corrected age, respectively (P<0.001). Likewise, bone SOS of the TF group increased from 2695+/-116 m/s at term to 2846+/-72 and 2978+/-83 m/s at three and six months, respectively (P<0.001). No statistically significant difference was found between the groups in terms of growth and bone SOS measurements. The levels of both bone turnover markers decreased significantly during the study period (P<0.001 for both groups).

CONCLUSION

Feeding with PDF after term had no short-term beneficial effect on bone strength and bone turn-over of VLBW infants.

Clinical-radiological features of fractures in premature infants--a review

Premature infants are more vulnerable to bone fractures than term infants for numerous reasons, directly or indirectly related to prematurity. Although the reported incidence of fractures in this vulnerable population is somewhat inconsistent, the increased risk is clear. Metabolic disorders, genetic disease, accidental trauma, and non-accidental injury can all account for fractures in premature infants, so that determining the etiology is of importance. This increased risk does not appear to continue into childhood. Thus, most of these fractures would be found in children <3 years of age, often within the first year of life. Unfortunately, this is the same age group in which the majority of non-accidental injury (NAI) cases, frequently presenting with fractures, are seen. Further confounding the diagnosis is the possibility of previously undiagnosed fractures from trauma during delivery, and fractures due to bone weakening by metabolic diseases. A multi-dimensional approach using a combination of diagnostic procedures is necessary to properly identify the location of the fractures, the bone structure and characteristics, and the history with regards to family situation and medical treatment. This paper reviews the potential factors related to fractures in premature infants and the differential diagnoses of child abuse fractures.

Changes in quantitative ultrasound in infants born at less than 32 weeks' gestation over the first 2 years of life: influence of clinical and biochemical changes

Studies in preterm infants show reduced speed of sound (SOS) as measured by quantitative ultrasound (QUS) during the immediate neonatal period. There is a scarcity of data on SOS changes following hospital discharge. The aim of this study was to assess SOS over the first 2 years in preterm infants. Infants were recruited from a neonatal follow-up clinic. Tibial QUS was performed using the Omnisense 7000P scanner. Thirty-nine infants born at <32 weeks' gestation had a single SOS measurement (median 3,203 m/second, range 2,609-3,495) which correlated with corrected gestational age (CGA) (r = 0.8, P < 0.005). The majority of measurements were within the manufacturer's reference range for term infants. SOS standard deviation score (SDS) in infants aged 0-6 months CGA demonstrated a negative correlation with duration of total parenteral nutrition (r = 0.7, P < 0.05) and a positive correlation with serum phosphate (r = 0.6, P < 0.05.) Two groups of infants had serial measurements: eight had measurements performed at term CGA and early infancy (early) and seven had measurements in later infancy (late). In the early group SOS SDS increased (P < 0.005), and the greatest increase in SOS over time occurred in infants with the lowest SOS at term (r = 0.9). In the late group there was no significant change over time. SOS SDS change did not show any correlation to weight SDS change. Catch-up in SOS occurs postterm in most infants by 6 months and is independent of postnatal growth. Infants with the lowest SOS at term have the fastest rate of catch-up. The opportunity for catch-up may be greatest in early infancy.

Bone disease of prematurity

Bone disease of prematurity is a complication of preterm birth. This article reviews the aetiology, treatment and prevention of bone disease of prematurity. Provision of adequate nutrition including energy, protein, and minerals is required for both treatment and prevention. Screening for bone disease is controversial. While further research is required quantitative ultrasound appears to be a promising tool for screening and monitoring response to therapy. Further research is needed before recommending physical activity to prevent bone disease of prematurity.

Quantitative ultrasound assessment of bone health in the neonate

For a number of reasons there is a need to explore reliable non-invasive methods for assessing bone health in neonates and young infants. Epidemiological studies suggest that early events in life may predispose the adult to degenerative diseases such as osteoporosis. Preterm infants have an increased risk of low bone mass because of limited bone mass accretion in utero and a greater need for bone nutrients. Despite improvements in neonatal care fractures still occur. The diagnosis of osteopaenia of prematurity remains difficult as there is no screening test which is both sensitive and specific. Biochemical indices are non-diagnostic, and plain X-rays in the absence of fractures are poor at diagnosing bone disease. Although dual energy X-ray absorptiometry is increasingly used to assess bone mineral status in newborn infants, the size and immobility of the scanner, the length of time to perform the scan and use of ionising radiation make it unsuitable for routine use in the setting of the fragile very low birth weight infant. Quantitative ultrasound (QUS) was first developed in 1984, as a non-ionising, portable and low cost method of assessing bone health. The measurements obtained from QUS are thought to be related not only to the mineral density of the bone but also to reflect parameters of bone quality and strength. Preliminary studies suggest that this technique may be a useful method of assessing changes in bone health in preterm infants, but the data need to be interpreted carefully. This review will concentrate on the methodology of QUS and the studies that have already been performed in neonates.