Neither altered incubation temperature during fetal development nor preferred rearing temperature improves leg bone characteristics of broilers.

The present study evaluated whether broiler femoral and tibiotarsal characteristics (as assessed at slaughter age) could be improved if birds were reared under their preferred temperature and whether continuous high or low incubation temperature during the fetal period improves bone characteristics of broilers reared under heat stress or thermal preference. Broiler breeder eggs were incubated from day 13 until hatching under cold (36 °C), control (37.5 °C), or hot (39 °C) temperatures. Under these conditions, the eggshell temperatures were 37.4 ± 0.1°C, 37.8 ± 0.15°C, and 38.8 ± 0.3°C, respectively. Then, broiler chicks were reared under control, preferred (determined previously in thermal preference test), or high temperatures. At day 42 of age, the broilers were weighed and euthanized, and femora and tibiotarsi collected to measure weight, length, diaphysis perimeter, breaking strength, maximum flexion, rigidity, ash, phosphorus, and calcium. Rearing under the preferred temperature did not affect broiler body weight or femoral and tibiotarsal characteristics (P > 0.05). In contrast, high rearing temperature, decreased the body weight, mineral contents of both bones, femoral breaking strength, and tibiotarsal rigidity (P < 0.05). Regarding incubation temperature effects, egg exposure to cold and hot temperatures during the fetal period minimized or avoided a few effects of high rearing temperature, such as those on femoral and tibiotarsal morphological characteristics, mineral composition, and mechanical properties at slaughter age (P < 0.05), but not all. In conclusion, rearing under the preferred broiler temperature did not improve the bone characteristics, and the negative effects of high rearing temperature on bone development were minimized but not completely prevented by high or low temperature incubation during the fetal period.

Light-dark rhythms during incubation of broiler chicken embryos and their effects on embryonic and post hatch leg bone development.

There are indications that lighting schedules applied during incubation can affect leg health at hatching and during rearing. The current experiment studied effects of lighting schedule: continuous light (24L), 12 hours of light, followed by 12 hours of darkness (12L:12D), or continuous darkness (24D) throughout incubation of broiler chicken eggs on the development and strength of leg bones, and the role of selected hormones in bone development. In the tibiatarsus and femur, growth and ossification during incubation and size and microstructure at day (D)0, D21, and D35 post hatching were measured. Plasma melatonin, growth hormone, and IGF-I were determined perinatally. Incidence of tibial dyschondroplasia, a leg pathology resulting from poor ossification at the bone's epiphyseal plates, was determined at slaughter on D35. 24L resulted in lower embryonic ossification at embryonic day (E)13 and E14, and lower femur length, and lower tibiatarsus weight, length, cortical area, second moment of area around the minor axis, and mean cortical thickness at hatching on D0 compared to 12L:12D especially. Results were long term, with lower femur weight and tibiatarsus length, cortical and medullary area of the tibiatarsus, and second moment of area around the minor axis, and a higher incidence of tibial dyschondroplasia for 24L. Growth hormone at D0 was higher for 24D than for 12L:12D, with 24L intermediate, but plasma melatonin and IGF-I did not differ between treatments, and the role of plasma melatonin, IGF-I, and growth hormone in this process was therefore not clear. To conclude, in the current experiment, 24L during incubation of chicken eggs had a detrimental effect on embryonic leg bone development and later life leg bone strength compared to 24D and 12L:12D, while the light-dark rhythm of 12L:12D may have a stimulating effect on leg health.

Effect of radioactive iodine-induced hypothyroidism on longitudinal bone growth during puberty in immature female rats.

Thyroid cancer in children, the most common endocrine malignancy, shows aggressive behavior and has a high recurrence rate after surgical ablation. Radioactive iodine (RAI) treatment is the most effective primary modality for medical ablation of juvenile thyroid cancer, and leads to intentional hypothyroidism. Although several negative impacts of hypothyroidism have been reported in children in response to other antithyroid agents, the combined effects of RAI exposure and hypothyroidism, on growing bones specifically, are unknown. In this study, we investigated the effect of RAI-induced hypothyroidism on the long bones during the pubertal growth spurt using immature female rats. Female Sprague-Dawley rats were randomly divided into a control group, and an RAI-treated group fed with RAI (0.37 MBq/g body weight) twice via gavage. After 4 weeks, we observed a significantly-reduced serum free thyroxine level in the RAI group. The latter group also displayed decreased body weight gain compared to the control. In addition, the lengths of long bones, such as the leg bones and vertebral column, as well as bone mineral content, were reduced in the RAI-treated animals. Our results confirm the negative impacts of RAI-induced thyroid deficiency during puberty on longitudinal bone growth and bone mineralization.

Artificial selection sheds light on developmental mechanisms of limb elongation.

Species diversity in limb lengths and proportions is thought to have evolved adaptively in the context of locomotor and habitat specialization, but the heritable cellular processes that drove this evolution within species are poorly understood. In this study, we take a novel "micro-evo-devo" approach, using artificial selection on relative limb length to amplify phenotypic variation in a population of mice, known as Longshanks, to examine the cellular mechanisms of postnatal limb development that contribute to intraspecific limb length variation. Cross-sectional growth data indicate that differences in bone length between Longshanks and random-bred controls are not due to prolonged growth, but to accelerated growth rates. Histomorphometric and cell proliferation assays on proximal tibial growth plates show that Longshanks' increased limb bone length is associated with an increased number of proliferative chondrocytes. In contrast, we find no differences in other growth plate cellular features known to underlie interspecific differences in limb bone size and shape, such as the rates of chondrocyte proliferation or the size and number of hypertrophic cells in the growth plate. These data suggest that small differences among individuals in the number of proliferating chondrocytes are a potentially important determinant of selectable intraspecific variation in individual limb bone lengths, independent of body size.

Short-Term Growth During Treatment with Inhaled Fluticasone Propionate/Formoterol, Fluticasone and Beclomethasone Treatment.

BACKGROUND: Fluticasone propionate/formoterol (FP/FORM) is a pressurized metered-dose inhaler (pMDI; Flutiform®) approved for use in adolescents and adults and under development for pediatric use. OBJECTIVE: To compare short-term growth in asthmatic children treated with FP/FORM, FP pMDI with valved holding chamber, and beclomethasone dipropionate (BDP) in a breath-actuated device. METHODS: Children with persistent asthma (n = 48; 5 to <12 years) participated in an assessor-blinded, randomized, three-way crossover trial with run in, wash out, and active treatment periods, each of 2 weeks duration. Interventions were FP/FORM 100/10 µg b.i.d. with an AeroChamber Plus® Flow-Vu® Spacer, FP pMDI (Flixotide®) 100 µg b.i.d. with a Volumatic® spacer, and extra-fine BDP breath-actuated inhaler (Aerobec®/QVAR® Autohaler®) 100 µg b.i.d. Lower leg growth rate (LLGR) was measured by knemometry. RESULTS: The least square (LS) mean difference in LLGR between FP/FORM and FP (per protocol population) was -0.006 mm/week (95% CI: -0.095 to 0.084; p < 0.001 for noninferiority [noninferiority margin -0.200 mm/week]). Both treatments elicited no change from baseline off-treatment growth rate. The LS mean treatment difference of FP/FORM versus BDP was 0.116 mm/week (95% CI: -0.004 to 0.235; p = 0.057) and of FP versus BDP 0.163 mm/week (95% CI: 0.078-0.249; p < 0.001). Results in the full analysis population were: FP/FORM versus FP -0.012 mm/week (95% CI: -0.080-0.056; p < 0.001); FP/FORM versus BDP 0.143 mm/week (95% CI: 0.064-0.222; p < 0.001); FP versus BDP 0.163 mm/week (95% CI: 0.093-0.233; p < 0.001). CONCLUSIONS: FP/FORM pMDI with AeroChamber and FP pMDI with Volumatic spacer did not affect lower leg growth, measured by knemometry, in asthmatic children. Conversely, extra-fine BDP from a breath-actuated inhaler resulted in short-term growth suppression.

Skeletal assessment and secular changes in knee development: a radiographic approach.

OBJECTIVES: The purpose of this study is to conduct an analysis of ossification patterns in the distal femoral, proximal tibial, and proximal fibular epiphyses, and the patella. The results generated from this analysis will be compared with previous standards published by Elgenmark () and Garn et al. () to determine if clinical and skeletal age assessment standards should be updated for contemporary Americans. MATERIALS AND METHODS: Using the Pediatric Radiology Interactive Atlas (Patricia), a total of 1,317 epiphyses were scored for presence or absence from radiographs of 1,056 white individuals born in or after 1990. Statistical modeling of epiphyseal appearance was conducted for all major percentiles, including the 5th and 95th percentiles through logistic regression. RESULTS: Compared with Elgenmark () and Garn et al. (), our data suggest that the distal femoral and proximal tibial epiphyses show overall earlier ossification, while the proximal fibular epiphysis shows later ossification. When examining the pooled sex 50th percentile for our data, we found that ossification timing differences are 1.2 weeks earlier in the distal femoral epiphysis, 2.1 weeks earlier in the proximal tibial epiphysis, and 1.4 years later in the proximal fibular epiphysis. DISCUSSION: The epiphyses that appear early in life, for example the distal femoral epiphysis, require gestational age information to accurately estimate appearance times. There are considerable differences between the ossification timing patterns presented in this study and those of previous standards, which did not include gestational ages. Several factors may explain the observed differences in the epiphyses of the knee including: the availability of gestational age information, the analysis of longitudinal versus cross-sectional data, differences in socioeconomic status and prenatal care, and secular change. KEYWORDS age estimation, growth standards, ossification, skeletal maturation, subadult/juvenile growth.

A method for estimating gestational age of fetal remains based on long bone lengths.

The estimation of gestational age (GA) in fetal human remains is important in forensic settings, particularly to assess fetal viability, in addition to often being the only biological profile parameter that can be assessed with some accuracy for non-adults. The length of long bone diaphysis is one of the most frequently used methods for fetal age estimation. The main objective of this study was to present a simple and objective method for estimating GA based on the measurements of the diaphysis of the femur, tibia, fibula, humerus, ulna, and radius. Conventional least squares regression equations (classical and inverse calibration approaches) and quick reference tables were generated. A supplementary objective was to compare the performance of the new formulae against previously published models. The sample comprised 257 fetuses (136 females and 121 males) with known GA (between 12 and 40 weeks) and was selected based on clinical and pathological information. All measurements were performed on radiographic images acquired in anonymous clinical autopsy records from spontaneous and therapeutic abortions in two Portuguese hospitals. The proposed technique is straightforward and reproducible. The models for the GA estimation are exceedingly accurate and unbiased. Comparisons between inverse and classical calibration show that both perform exceptionally well, with high accuracy and low bias. Also, the newly developed equations generally outperform earlier methods of GA estimation in forensic contexts. Quick reference tables for each long bone are now available. The obtained models for the estimation of gestational age are of great applicability in forensic contexts.

Developmental patterns of bilateral asymmetry in ancestral puebloans.

OBJECTIVES: Producing and maintaining a bilaterally symmetric phenotype throughout the lifespan is energetically demanding. Over the course of an individual's life, various intrinsic and external stressors impact the growth trajectory. These perturbations can compromise the allocation of energetic resources to processes that maintain developmental precision, potentially resulting in bilateral asymmetry (BA). Because different stressors are present during the lifespan, BA is a valuable tool for examining the unique factors impacting symmetrical growth and development. This study examines BA in paired long bones across a developmental skeletal series. METHODS: The humeri, radii, femora, and tibiae of 198 individuals from Ancestral Puebloan New Mexico (919-1670 CE) are analyzed to explore BA across development. Individuals are separated into five age categories, and by sex when possible, to explore patterns of BA. RESULTS: Significant BA is found in the bones of the upper limb when the interaction between bone and age is examined. Results suggest that BA in the humerus and radius becomes more right-biased with age. These directional trends are not observed in the lower limbs. Division into age categories illuminates patterns of asymmetry associated with age-related activities and physiological maturity, indicating that BA is differentially affected by varying environmental stressors across development. CONCLUSIONS: Our findings support the hypothesis that BA in long bones is influenced by environmental stressors that impact an individual's ability to produce symmetric morphological traits over the lifespan. Right-biased BA in the upper limb bones indicates that this variation from a symmetric ideal is strongly influenced by handedness resulting from habitual manual activities. Am. J. Hum. Biol. 28:421-430, 2016. © 2015 Wiley Periodicals, Inc.

Make No Bones about It: Long Bones Scale Isometrically.

Long bones are far from being simple cylinders, so how is the relative positioning of their various features maintained during growth? A new study shows that growth is isometric and that drift from the correct position is minimized. Read the Research Article.

Isometric Scaling in Developing Long Bones Is Achieved by an Optimal Epiphyseal Growth Balance.

One of the major challenges that developing organs face is scaling, that is, the adjustment of physical proportions during the massive increase in size. Although organ scaling is fundamental for development and function, little is known about the mechanisms that regulate it. Bone superstructures are projections that typically serve for tendon and ligament insertion or articulation and, therefore, their position along the bone is crucial for musculoskeletal functionality. As bones are rigid structures that elongate only from their ends, it is unclear how superstructure positions are regulated during growth to end up in the right locations. Here, we document the process of longitudinal scaling in developing mouse long bones and uncover the mechanism that regulates it. To that end, we performed a computational analysis of hundreds of three-dimensional micro-CT images, using a newly developed method for recovering the morphogenetic sequence of developing bones. Strikingly, analysis revealed that the relative position of all superstructures along the bone is highly preserved during more than a 5-fold increase in length, indicating isometric scaling. It has been suggested that during development, bone superstructures are continuously reconstructed and relocated along the shaft, a process known as drift. Surprisingly, our results showed that most superstructures did not drift at all. Instead, we identified a novel mechanism for bone scaling, whereby each bone exhibits a specific and unique balance between proximal and distal growth rates, which accurately maintains the relative position of its superstructures. Moreover, we show mathematically that this mechanism minimizes the cumulative drift of all superstructures, thereby optimizing the scaling process. Our study reveals a general mechanism for the scaling of developing bones. More broadly, these findings suggest an evolutionary mechanism that facilitates variability in bone morphology by controlling the activity of individual epiphyseal plates.

Genome-wide Analysis of Body Proportion Classifies Height-Associated Variants by Mechanism of Action and Implicates Genes Important for Skeletal Development.

Human height is a composite measurement, reflecting the sum of leg, spine, and head lengths. Many common variants influence total height, but the effects of these or other variants on the components of height (body proportion) remain largely unknown. We studied sitting height ratio (SHR), the ratio of sitting height to total height, to identify such effects in 3,545 African Americans and 21,590 individuals of European ancestry. We found that SHR is heritable: 26% and 39% of the total variance of SHR can be explained by common variants in European and African Americans, respectively, and global European admixture is negatively correlated with SHR in African Americans (r(2) ≈ 0.03). Six regions reached genome-wide significance (p < 5 × 10(-8)) for association with SHR and overlapped biological candidate genes, including TBX2 and IGFBP3. We found that 130 of 670 height-associated variants are nominally associated (p < 0.05) with SHR, more than expected by chance (p = 5 × 10(-40)). At these 130 loci, the height-increasing alleles are associated with either a decrease (71 loci) or increase (59 loci) in SHR, suggesting that different height loci disproportionally affect either leg length or spine/head length. Pathway analyses via DEPICT revealed that height loci affecting SHR, and especially those affecting leg length, show enrichment of different biological pathways (e.g., bone/cartilage/growth plate pathways) than do loci with no effect on SHR (e.g., embryonic development). These results highlight the value of using a pair of related but orthogonal phenotypes, in this case SHR with height, as a prism to dissect the biology underlying genetic associations in polygenic traits and diseases.

Ontogenetic changes in intralimb proportions in a Romano-Christian period sample from the Dakhleh Oasis, Egypt.

OBJECTIVES: The purpose of this study is to document the appearance of adult patterns in intralimb indices during ontogeny in a skeletal sample from the Kellis 2 cemetery, Dakhleh Oasis, Egypt. In addition, this study explores evolvability in intralimb indices to understand relative differences in sensitivity to ecogeographic variables. METHODS: Brachial and crural indices were compared across age cohorts with Welch's ANOVA tests and post-hoc Dunnett-Tukey-Kramer (DTK) pairwise multiple comparison tests. Spearman's rank correlation coefficients were used to examine developmental conservation and evolvability in intralimb proportions. RESULTS: Brachial and crural indices are greatest in the fetus/perinate cohort as compared to all other cohorts, decrease during infancy and early childhood, and increase during middle/late childhood. The adult pattern in the brachial index is first evident in infancy, but is not maintained throughout development. Conversely, the adult pattern in the crural index appears during early childhood and is maintained throughout development. The brachial index shows a higher degree of evolvability than the crural index in utero. CONCLUSIONS: The shifting pattern in intralimb proportions during development in the Kellis 2 sample is similar to that previously reported from globally diverse samples, which likely reflects the differential growth acceleration of proximal and distal intralimb skeletal elements during ontogeny. The brachial index may be more responsive to climatic conditions while the crural index may be more conserved due to functional demands. The data indicate that Kellis 2 juveniles were under strong selective pressures from climatic factors.

Ontogenetic changes in limb bone structural proportions in mountain gorillas (Gorilla beringei beringei).

Behavioral studies indicate that adult mountain gorillas (Gorilla beringei) are the most terrestrial of all nonhuman hominoids, but that infant mountain gorillas are much more arboreal. Here we examine ontogenetic changes in diaphyseal strength and length of the femur, tibia, humerus, radius, and ulna in 30 Virunga mountain gorillas, including 18 immature specimens and 12 adults. Comparisons are also made with 14 adult western lowland gorillas (Gorilla gorilla gorilla), which are known to be more arboreal than adult mountain gorillas. Infant mountain gorillas have significantly stronger forelimbs relative to hind limbs than older juveniles and adults, but are nonsignificantly different from western lowland gorilla adults. The change in inter-limb strength proportions is abrupt at about two years of age, corresponding to the documented transition to committed terrestrial quadrupedalism in mountain gorillas. The one exception is the ulna, which shows a gradual increase in strength relative to the radius and other long bones during development, possibly corresponding to the gradual adoption of stereotypical fully pronated knuckle-walking in older juvenile gorillas. Inter-limb bone length proportions show a contrasting developmental pattern, with hind limb/forelimb length declining rapidly from birth to five months of age, and then showing no consistent change through adulthood. The very early change in length proportions, prior to significant independent locomotion, may be related to the need for relatively long forelimbs for climbing in a large-bodied hominoid. Virunga mountain gorilla older juveniles and adults have equal or longer forelimb relative to hind limb bones than western lowland adults. These findings indicate that both ontogenetically and among closely related species of Gorilla, long bone strength proportions better reflect actual locomotor behavior than bone length proportions.

Genomic regions affecting backfat thickness and cannon bone circumference identified by genome-wide association study in a Duroc pig population.

We performed a genome-wide association study using the porcine 60K SNP array to detect QTL regions for nine traits in a three-generational Duroc samples (n = 651), viz. generations 1, 2 and 3 from a population selected over five generations using a closed nucleus breeding scheme. We applied a linear mixed model for association mapping to detect SNP effects, adjusting for fixed effects (sex and season) and random polygenic effects (reflecting genetic relatedness), and derived a likelihood ratio statistic for each SNP using the efficient mixed-model association method. We detected a region on SSC6 for backfat thickness (BFT) and on SSC7 for cannon bone circumference (CANNON), with a genome-wide significance of P < 0.01 after Bonferroni correction. These regions had been detected previously in other pig populations. Six genes are located in the BFT-associated region, while the CANNON-associated region includes 66 genes. In the future, significantly associated SNPs, derived by sequencing the coding regions of the six genes in the BFT region, can be used in marker-assisted selection of BFT, whereas haplotypes constructed from the SSC7 region with strong LD can be used to select for the CANNON trait in our resource family.

Effects of physical activity and muscle quality on bone development in girls.

INTRODUCTION: Poor muscle quality and sedentary behavior are risk factors for metabolic dysfunction in children and adolescents. However, because longitudinal data are scarce, relatively little is known about how changes in muscle quality and physical activity influence bone development. PURPOSE: In a 2-yr longitudinal study, we examined the effects of physical activity and changes in muscle quality on bone parameters in young girls. METHODS: The sample included 248 healthy girls age 9-12 yr at baseline. Peripheral quantitative computed tomography was used to measure calf and thigh muscle density, an indicator of skeletal muscle fat content or muscle quality, as well as bone parameters at diaphyseal and metaphyseal sites of the femur and tibia. Physical activity was assessed using a validated questionnaire specific for youth. RESULTS: After controlling for covariates in multiple regression models, increased calf muscle density was independently associated with greater gains in cortical (ß = 0.13, P < 0.01) and trabecular (ß = 0.25, P < 0.001) volumetric bone mineral density and the bone strength index (ß = 0.25, P < 0.001) of the tibia. Importantly, these relationships were generalized, as similar changes were present at the femur. Associations between physical activity and changes in bone parameters were weaker than those observed for muscle density. Nevertheless, physical activity was significantly (all P < 0.05) associated with greater gains in trabecular volumetric bone mineral density and the bone strength index of the distal femur. CONCLUSIONS: These findings suggest that poor muscle quality may put girls at risk for suboptimal bone development. Physical activity is associated with more optimal gains in weight-bearing bone density and strength in girls, but to a lesser extent than changes in muscle quality.

Detection of irradiated frog (Limnonectes macrodon) leg bones by multifrequency EPR spectroscopy.

The free radicals of irradiated frog Limnonectes macrodon leg bones tissue were studied by electron paramagnetic resonance in both X and Q bands. The kinetic behaviour, the activation energy as well as the thermal stability of the radiation-induced radicals in bone tissue were investigated by means of both isothermal and isochronal annealing. Unirradiated bone tissue displayed the presence of Mn(2+) ions at both frequencies, while a week EPR singlet was evidenced only at 34 GHz. When irradiated with (60)Co gamma ray, the EPR spectra completely changed their patterns and intensity, the overall spectra provin, at both frequencies, to be typical axial ones. The 100°C isothermal annealing studies attested the existence of two different free radical species, significantly more labile than in the case of mammal bone tissues. At the same time, the Arrhenius plot of 15 kGy irradiated bones evidenced two different kinetic regimes with two different activation energies.

Pubertal timing predicts leg length and childhood body mass index predicts sitting height in young adult men.

OBJECTIVE: To investigate the impact of pubertal timing and childhood body mass index (BMI), both within normal range, on adult anthropometrics. STUDY DESIGN: Detailed growth charts were retrieved for the men participating in the population-based Gothenburg Osteoporosis and Obesity Determinants study. Age at peak height velocity and childhood BMI were calculated (n = 527), and anthropometric measurements were performed. RESULTS: Analysis of variance analysis of tertiles according to age at peak height velocity demonstrated that the early peak height velocity tertile had a lower adult height (180.9 ± 6.8 cm) compared with the middle tertile group (182.7 ± 6.9 cm, P < .05), and this difference was attributable to shorter leg length. No difference was seen for sitting height. In contrast, analysis of tertiles according to childhood BMI demonstrated low sitting height in the low BMI tertile (93.7 ± 3.3 cm for low, 94.6 ± 3.3, for middle, and 94.8 ± 3.3 cm for high childhood BMI tertiles, P < .05 and P < .01, respectively), but childhood BMI did not affect adult height and leg length. CONCLUSION: We demonstrate that subjects with early pubertal timing have reduced adult height and leg length, and subjects with low childhood BMI have reduced adult sitting height. Thus childhood body composition and pubertal timing have different impact on trunk growth and growth of long bones.

Lesiones de ligamento cruzado anterior en niños con cartilagos abiertos: tecnica quirurgica sugerida: investigacion bibliografica / Anterior cruciate ligament injuries in children with open physis: suggested surgical technique: bibliographic survey

Se describe el mecanismo de acción, historia natural, presentación clínica y distintos tipos de tratamiento de las lesiones de LCA en niños con cartílago s abiertos y sus complicaciones. La verdadera incidencia de lesión de LCA en niños con cartílagos abiertos es desconocida en Argentina. En el pasado estas lesiones eran subdiagnosticadas, en los últimos años se ha observado un mayor número de estos pacientes. Este aumento ha sido atribuido a un mejor diagnóstico, mejor comprensión de la patología en este grupo etario y a un incremento en la exigencia y participación de los niños en deportes de riesgo. Es importante establecer el potencial de crecimiento ya que tanto éste como el cierre fisiológico de la fisis es variable y deben ser tenidos en cuenta para una adecuada planificación de la técnica quirúrgica y para determinar los eventuales riesgos del compromiso de la fisis. El diagnóstico de lesión de LCA se basa principalmente en el antecedente traumático previo y el examen fisico. La RMN es de utilidad como estudio complementario sobre todo en casos donde la presentación clínica no es clara. El tratamiento de las lesiones de LCA en pacientes esqueléticamente inmaduros es controvertido. El manejo tradicional de estas lesiones ha sido conservador debido al riesgo de lesión de la fisis y desarrollo de alteraciones del crecimiento (discrepancia de miembros inferiores y deformidades angulares). Sin embargo, la bibliografia actual demuestra que la reconstrucción intraarticular precoz y agresiva, permite restaurar la estabilidad articular, retomar al nivel previo de actividad deportiva, disminuir el riesgo de lesiones meniscales secundarias y patología intraarticular degenerativa, con un riesgo mínimo de daño del cartílago de crecimiento con la técnica adecuada. Las distintas opciones quirúrgicas incluyen reparación primaria del ligamento, reconstrucciones extraarticulares, reconstrucción combinada intra y extra articular y reconstrucciones intraarticulares ...(AU)

Lesiones de ligamento cruzado anterior en niños con cartilagos abiertos: tecnica quirurgica sugerida: investigacion bibliografica / Anterior cruciate ligament injuries in children with open physis: suggested surgical technique: bibliographic survey

Se describe el mecanismo de acción, historia natural, presentación clínica y distintos tipos de tratamiento de las lesiones de LCA en niños con cartílago s abiertos y sus complicaciones. La verdadera incidencia de lesión de LCA en niños con cartílagos abiertos es desconocida en Argentina. En el pasado estas lesiones eran subdiagnosticadas, en los últimos años se ha observado un mayor número de estos pacientes. Este aumento ha sido atribuido a un mejor diagnóstico, mejor comprensión de la patología en este grupo etario y a un incremento en la exigencia y participación de los niños en deportes de riesgo. Es importante establecer el potencial de crecimiento ya que tanto éste como el cierre fisiológico de la fisis es variable y deben ser tenidos en cuenta para una adecuada planificación de la técnica quirúrgica y para determinar los eventuales riesgos del compromiso de la fisis. El diagnóstico de lesión de LCA se basa principalmente en el antecedente traumático previo y el examen fisico. La RMN es de utilidad como estudio complementario sobre todo en casos donde la presentación clínica no es clara. El tratamiento de las lesiones de LCA en pacientes esqueléticamente inmaduros es controvertido. El manejo tradicional de estas lesiones ha sido conservador debido al riesgo de lesión de la fisis y desarrollo de alteraciones del crecimiento (discrepancia de miembros inferiores y deformidades angulares). Sin embargo, la bibliografia actual demuestra que la reconstrucción intraarticular precoz y agresiva, permite restaurar la estabilidad articular, retomar al nivel previo de actividad deportiva, disminuir el riesgo de lesiones meniscales secundarias y patología intraarticular degenerativa, con un riesgo mínimo de daño del cartílago de crecimiento con la técnica adecuada. Las distintas opciones quirúrgicas incluyen reparación primaria del ligamento, reconstrucciones extraarticulares, reconstrucción combinada intra y extra articular y reconstrucciones intraarticulares ...

Methodology and implications of knemometry in growth assessment of inhaled glucocorticoids.

When validated recommendations for standardization and measurement procedures are used short-term assessment of lower leg growth by knemometry is a highly accurate and reproducible method for assessment of systemic activity of inhaled glucocorticoids. Crossover and parallel designs applying consistent measurement intervals can be used. Crossover designs with a single-blind run in and washout and double-blind active periods are as sensitive as designs using randomized placebo periods. In populations of children, short-term knemometry appears to be capable of defining specific glucocorticoids, application devices and doses that do not suppress long-term height growth. Although no specific cut-off level can be identified in individuals from the available randomized, double-blind short-term knemometry and intermediate-term height growth rate studies, good evidence have been provided that if the short-term lower leg growth suppression in populations of children is higher than approximately 25%, the risk of intermediate-term growth suppression becomes significant with a mean height growth rate retardation in the range of approximately 0.5-1.5 cm during the first year of treatment. Short-term knemometry should be performed as an integral part of the safety assessments of new inhaled glucocorticoids and inhalation devices in children with asthma, before intermediate-term height growth evaluations are initiated.