Changes in cortical hemodynamics with the emergence of skilled motor ability in infants: An fNIRS study.

The brain activity changes during infancy that underpin the emergence of functional motor skills, such as reaching and stepping, are not well understood. The current study used functional near-infrared spectroscopy (fNIRS) to examine the hemodynamic response across the frontal, mid-coronal plane (sensorimotor cortex) and external occipital protuberance (cerebellar cortex) regions of typically developing infants (5 to 13 months) during reach-to-grasp or supported treadmill stepping behaviour. Motor ability was assessed using the third edition of the Motor Subscale of the Bayley Scales of Infant Development (BSID-III). Infants with enhanced motor ability demonstrated greater oxy-hemoglobin (HbO) concentration in the contralateral anterior mid-coronal and frontal-dorsal areas during right-handed reach-to-grasp. During bilateral reaching behavior, infants with enhanced motor ability showed greater HbO increases in right frontal-dorsal regions and lower HbO increases in left anterior mid-coronal areas. In contrast, infants' motor ability was associated with changes in de-oxyhemoglobin (HbR) concentration in the ipsilateral anterior mid-coronal, contralateral frontal and left external occipital protuberance regions during left-handed reaching behavior. These relationships between upper limb hemodynamics and infant motor ability are consistent with increased lateralization and cognitive-motor coupling as motor skills emerge. During stepping behavior, infants with enhanced motor ability demonstrated smaller increases in HbR concentration in the bilateral external occipital protuberance region consistent with an emerging efficiency as cruising and independent stepping behavior is still nascent. Together, the current results identify several distinct neural markers of functional motor ability during infancy that may be relevant to diagnostic testing and rehabilitation of developmental movement disorders.

Early activating somatic PIK3CA mutations promote ectopic muscle development and upper limb overgrowth.

PIK3CA-related overgrowth spectrum is a group of rare genetic disorders with asymmetric overgrowth caused by somatic mosaic PIK3CA mutations. Here, we report clinical data and molecular findings from two patients with congenital muscular upper limb overgrowth and aberrant anatomy. During debulking surgery, numerous ectopic muscles were found in the upper limbs of the patients. DNA sequencing, followed by digital polymerase chain reaction, was performed on DNA extracted from biopsies from hypertrophic ectopic muscles and identified the somatic mosaic PIK3CA hotspot mutations c.3140A > G, p.(His1047Arg) and c.1624G > A, p.(Glu542Lys) in a male (patient 1) and a female (patient 2) patient, respectively. Patient 1 had four ectopic muscles and unilateral isolated muscular overgrowth while patient 2 had 13 ectopic muscles and bilateral isolated muscular overgrowth of both upper limbs, indicating that her mutation occurred at early pre-somitic mesoderm state. The finding of PIK3CA mutations in ectopic muscles highlights the importance of PIK3CA in cell fate in early human embryonic development. Moreover, our findings provide evidence that the disease phenotype depends on the timing of PIK3CA mutagenesis during embryogenesis and confirm the diagnostic entity PIK3CA-related muscular overgrowth with ectopic accessory muscles.

Upper limb muscle overgrowth with hypoplasia of the index finger: a new over-growth syndrome caused by the somatic PIK3CA mutation c.3140A>G.

BACKGROUND: Scientists have previously described an overgrowth syndrome in Saudi patients and named it 'Upper limb muscle overgrowth with hypoplasia of the index finger' syndrome. CASE PRESENTATION: We describe a new case and document that the syndrome is caused by the somatic PIK3CA mutation c.3140A>G, p.His1047Arg. We also recruited one of the previously reported cases and found the same somatic mutation in the affected muscles. A wider classification of 'PIK3CA-related pathology spectrum' is presented which includes cancer, benign skin lesions/tumors, Cowden syndrome, isolated vascular malformations and various overgrowth syndromes. The latter entity is sub-divided into 3 sub-groups: overgrowth with brain involvement, overgrowth with multiple lipomatosis, and overgrowth without brain involvement/multiple lipomatosis. CONCLUSION: Our literature review indicated that "upper limb muscle overgrowth with hypoplasia of the index finger" is not as rare as previously thought to be. This overgrowth syndrome is unique and is caused by the somatic PIK3CA mutation c.3140A>G.

Age-related changes in upper limb motion during typical development.

BACKGROUND AND AIM: Understanding the maturation of upper limb (UL) movement characteristics in typically developing (TD) children is key to explore UL deficits in those with neurodevelopmental disorders. Three-dimensional motion analysis (3DMA) offers a reliable tool to comprehensively evaluate UL motion. However, studies thus far mainly focused on specific pre-defined parameters extracted from kinematic waveforms. Here, we investigated age-related differences in UL movement characteristics over the entire movement cycle in TD children. PARTICIPANTS AND METHODS: We assessed the non-dominant UL of 60 TD children (mean age 10y3m±3y1m) using 3DMA during eight tasks: reaching (forwards (RF), upwards (RU), sideways (RS)), reach-to-grasp (sphere (RGS), vertical cylinder (RGV)) and activities-of-daily-living mimicking tasks (hand-to-head (HTH), hand-to-mouth (HTM), hand-to-shoulder (HTS)). We investigated differences between four age-groups (5-7y, 8-10y, 11-12y, 13-15y) in: (1) spatiotemporal parameters (movement duration, peak velocity, time-to-peak velocity and trajectory straightness), and (2) 12 UL joint angles, using Statistical Parametric Mapping (SPM). RESULTS: We found that the 5-7y children moved with lower peak velocity and less straight trajectories compared to the 11-12y group (peak velocity: RS, HTS, p<0.01; trajectory: RU, RS, RGV, HTS, p<0.01) and the 13-15y group (peak velocity: RF, RS, RGS, RGV, HTH, HTS, p<0.01; trajectory, all tasks, p<0.01). The 5-7y children showed increased scapular protraction compared to older children (8-10y and 11-12y, HTS), as well as increased scapular medial rotation compared to the 13-15y group (RGS). During RU, the 5-7y children moved more towards the frontal plane (shoulder), unlike the 13-15y group. Lastly, the 5-7y group used less elbow flexion than older children (11-12y and 13-15y) during HTH and HTS. DISCUSSION AND CONCLUSION: In conclusion, our results point toward a maturation in UL movement characteristics up to age 11-12y, when UL motion seemed to reach a plateau. The reference values provided in this study will help to further optimize the interpretation of UL deficits in children with neurodevelopmental disorders.

Developmental progression and side specialization in upper-limb movements from 4 to 8 years in children born preterm and fullterm.

This study investigated developmental changes and differences in upper-limb movement organization from 4 to 8 years of age in children born preterm (PT) and fullterm (FT). Kinematic recordings of precision-demanding unimanual movements and lateral assessments were carried out in 37 children (18 PT). All children, particularly children born PT, displayed considerable gain in movement kinematics. Contrary to controls, children born PT displayed persistently less-evident side preference. Gestational age (GA) contributed significantly to kinematic differences shown, with larger upper-limb deviances in the lowest GAs, in agreement with cross-sectional findings of altered hemispheric connections and delayed side-specialization among children born very PT.

An assessment of postcranial indices, ratios, and body mass versus eco-geographical variables of prehistoric Jomon, Yayoi agriculturalists, and Kumejima Islanders of Japan.

OBJECTIVES: We explore variations in body and limb proportions of the Jomon hunter-gatherers (14,000-2500 BP), the Yayoi agriculturalists (2500-1700 BP) of Japan, and the Kumejima Islanders of the Ryukyus (1600-1800 AD) with 11 geographically diverse skeletal postcranial samples from Africa, Europe, Asia, Australia, and North America using brachial-crural indices, femur head-breadth-to-femur length ratio, femur head-breadth-to-lower-limb-length ratio, and body mass as indicators of phenotypic climatic adaptation. Specifically, we test the hypothesis that variation in limb proportions seen in Jomon, Yayoi, and Kumejima is a complex interaction of genetic adaptation; development and allometric constraints; selection, gene flow and genetic drift with changing cultural factors (i.e., nutrition) and climate. METHODS: The skeletal data (1127 individuals) were subjected to principle components analysis, Manly's permutation multiple regression tests, and Relethford-Blangero analysis. RESULTS: The results of Manly's tests indicate that body proportions and body mass are significantly correlated with latitude, and minimum and maximum temperatures while limb proportions were not significantly correlated with these climatic variables. Principal components plots separated "climatic zones:" tropical, temperate, and arctic populations. The indigenous Jomon showed cold-adapted body proportions and warm-adapted limb proportions. Kumejima showed cold-adapted body proportions and limbs. The Yayoi adhered to the Allen-Bergmann expectation of cold-adapted body and limb proportions. Relethford-Blangero analysis showed that Kumejima experienced gene flow indicated by high observed variances while Jomon experienced genetic drift indicated by low observed variances. CONCLUSIONS: The complex interaction of evolutionary forces and development/nutritional constraints are implicated in the mismatch of limb and body proportions.

Ontogenetic changes in limb postures and their impact on effective limb length in baboons (Papio cynocephalus).

OBJECTIVES: Digitigrade hand and foot postures and extended elbows and knees are considered adaptations to running in cursorial mammals because they increase effective limb lengths (ELLs). However, the relationship between digitigrady and ELL in primates is not well understood. We documented the ontogeny of limb postures in baboons to better understand the function of digitigrady during walking. We hypothesized that the hand and foot would become more elevated and the elbow and knee more extended, leading to increased relative ELLs throughout ontogeny. MATERIALS AND METHODS: Longitudinal kinematic data were collected on four infant yellow baboons (Papio cynocephalus) as they aged from two to nine months, and again at two to three years. Hand/foot postures, elbow/knee angles, relative fore/hind limb ELLs, and dimensionless velocity were measured for 404 symmetrical walking strides. RESULTS: Digitigrade hand and foot postures were preferred at all ages. The elbow extended slightly and the knee flexed slightly with age. Elevated proximal hands, extended elbows, and extended knees were associated with long relative ELLs. For a given age, relative hind limb ELL was longer than relative forelimb ELL. DISCUSSION: In the forelimb, digitigrade hand postures and extended elbows function to increase relative ELL at slow walking velocity. Increased forelimb ELL may be an attempt to equalize forelimb and hind limb ELLs in baboons with an absolutely longer hind limb. Pedal digitigrady is not a main contributing factor to hind limb ELL. Results suggest that manual and pedal digitigrady in terrestrial cercopithecoids does not function to increase velocity.

Beneficial Effect of the Nutritional Support in Children Who Underwent Hematopoietic Stem Cell Transplant.

OBJECTIVES: The aim of this study was to evaluate nutritional status in children who underwent hematopoietic stem cell transplant compared with a healthy control group. A secondary aim was to utilize mid-upper arm circumference as a measure of nutritional status in these groups of children. MATERIALS AND METHODS: Our study group included 40 children (18 girls, 22 boys) with mean age of 9.2 ± 4.6 years (range, 2-17 y) who underwent hematopoietic stem cell transplant. Our control group consisted of 20 healthy children (9 girls, 11 boys). The children were evaluated at admission to the hospital and followed regularly 3, 6, 9, and 12 months after discharge from the hospital. RESULTS: In the study group, 27 of 40 patients (67.5%) received nutritional support during hematopoietic stem cell transplant, with 15 patients (56%) receiving enteral nutrition, 6 (22%) receiving total parenteral nutrition, and 6 (22%) receiving enteral and total parenteral nutrition. Chronic malnutrition rate in the study group was 47.5% on admission to the hospital, with the control group having a rate of 20%. One year after transplant, the rate decreased to 20% in the study group and 5% in the control group. The mid-upper arm circumference was lower in children in the study group versus the control group at the beginning of the study (P < .05). However, there were no significant differences in mid-upper arm circumference measurements between groups at follow-up examinations (P > .05). During follow-up, all anthropometric measurements increased significantly in both groups. CONCLUSIONS: Monitoring nutritional status and initiating appropriate nutritional support improved the success of hematopoietic stem cell transplant and provided a more comfortable process during the transplant period. Furthermore, mid-upper arm circumference is a more sensitive, useful, and safer parameter that can be used to measure nutritional status of children who undergo hematopoietic stem cell transplant.

Esqueletogênese em punaré (Thrichomys laurentinus- Rodentia, Echimyidae) / Skeletogenesis in punare (Thrichomys laurentinus - Rodentia, Echimyidae)

O objetivo deste estudo foi descrever o desenvolvimento do esqueleto do punaré (Thrichomys laurentinus). Para tanto, foram utilizados 11 embriões e 12 fetos em diferentes estágios de desenvolvimento, sendo divididos em 4 grupos de acordo com o período gestacional. As amostras foram obtidas no Centro de Multiplicação de Animais Silvestres da Universidade Federal Rural do Semi-Árido, Mossoró-RN, Brasil. Após fixados em formol (10%) ou glutaraldeído (2,5%), foi realizada a analise morfológica com auxílio de lupa, sendo as características macroscópicas fotodocumentadas. Análises de raios-x e coloração por alizarina red foram realizadas para melhor compreensão do desenvolvimento ósseo. Nas análises de raio-x os embriões não apresentaram nenhuma radiopacidade, ao contrário dos fetos que apresentavam radiopacidade gradual ao longo dos grupos. No grupo II houve aumento de radiopacidade na região da coluna vertebral e das regiões mandibular e maxilar. No grupo III a radiopacidade estava aumentada nos membros pélvicos, nas costelas e na região frontal e no grupo IV nos membros torácicos e nas regiões occipital, temporal e frontal do crânio. Tais características foram confirmadas pelas analises histológicas e pela técnica de Alizarina Red. Com isso podemos concluir que o conhecimento acerca da embriologia do sistema ósseo normal é fundamental para o entendimento dos efeitos adversos causados pela nutrição e uso de drogas durante o desenvolvimento.(AU)

The aim of this study was to describe the skeletogenesis in punaré (Thrichomys laurentinus). We used 11 embryos and 12 fetuses in different stages of development, allocated into 4 groups. Samples were obtained from the Multiplication Center of Wild Animals, at Federal Rural University of the Semi-Arid, Mossoro/RN, Brazil. After fixed in formalin (10%) or glutaraldehyde (2.5%) the morphological analysis was performed with a magnifying glass, and the macroscopic characteristics were photographed. Analysis of X-rays and alizarin red staining was made to better understand the development of bone structures. In x-ray analysis, it was possible to verify that the embryos showed no radiopacity, unlike fetuses that had gradual radiopacity along of the groups. In group II, there was an increase in radiopacity in the spine, mandibular and maxillary regions. In group III, the radiopacity was increased in the hind limbs, ribs and in the frontal region, and group IV showed higher radiopacity in the thoracic limbs and occipital, temporal and frontal skull. These characteristics were confirmed by histological and alizarin red analysis. We concluded that the knowledge of normal skeletal embryology is critical for understanding of adverse effects caused by nutrition and use of drugs during the development.(AU)

Adaptation of physiological cross-sectional area and serial number of sarcomeres after tendon transfer of rat muscle.

Tendon transfer surgery to a new extensor insertion was performed for musculus flexor carpi ulnaris (FCU) of young adult rats, after which animals were allowed to recover. Mechanical properties and adaptive effects on body mass, bone growth, serial number of sarcomeres, and muscle physiological cross-sectional area were studied. Between the transfer and control groups, no differences were found for body mass and forearm length growth. In contrast, transferred muscles had a 19% smaller physiological cross-sectional area and 25% fewer sarcomeres in series within its muscle fibers than control muscles, i.e., a deficit in muscle belly growth is present. Our present results confirm our the length of previous work showing a limited capability of changing the adapted transferred FCU muscle belly, as the muscle-tendon complex is stretched, so that most of the acute FCU length change must originate from the tendon. This should most likely be attributed to surgery-related additional and/or altered connective tissue linkages at the muscle-tendon boundary. The substantially increased FCU tendon length found, after recovery from surgery and adaptation to the conditions of the transferred position, is likely to be related to such enhanced stretching of the FCU tendon.

Anatomical Network Comparison of Human Upper and Lower, Newborn and Adult, and Normal and Abnormal Limbs, with Notes on Development, Pathology and Limb Serial Homology vs. Homoplasy.

How do the various anatomical parts (modules) of the animal body evolve into very different integrated forms (integration) yet still function properly without decreasing the individual's survival? This long-standing question remains unanswered for multiple reasons, including lack of consensus about conceptual definitions and approaches, as well as a reasonable bias toward the study of hard tissues over soft tissues. A major difficulty concerns the non-trivial technical hurdles of addressing this problem, specifically the lack of quantitative tools to quantify and compare variation across multiple disparate anatomical parts and tissue types. In this paper we apply for the first time a powerful new quantitative tool, Anatomical Network Analysis (AnNA), to examine and compare in detail the musculoskeletal modularity and integration of normal and abnormal human upper and lower limbs. In contrast to other morphological methods, the strength of AnNA is that it allows efficient and direct empirical comparisons among body parts with even vastly different architectures (e.g. upper and lower limbs) and diverse or complex tissue composition (e.g. bones, cartilages and muscles), by quantifying the spatial organization of these parts-their topological patterns relative to each other-using tools borrowed from network theory. Our results reveal similarities between the skeletal networks of the normal newborn/adult upper limb vs. lower limb, with exception to the shoulder vs. pelvis. However, when muscles are included, the overall musculoskeletal network organization of the upper limb is strikingly different from that of the lower limb, particularly that of the more proximal structures of each limb. Importantly, the obtained data provide further evidence to be added to the vast amount of paleontological, gross anatomical, developmental, molecular and embryological data recently obtained that contradicts the long-standing dogma that the upper and lower limbs are serial homologues. In addition, the AnNA of the limbs of a trisomy 18 human fetus strongly supports Pere Alberch's ill-named "logic of monsters" hypothesis, and contradicts the commonly accepted idea that birth defects often lead to lower integration (i.e. more parcellation) of anatomical structures.

Phenotypic dissection of bone mineral density reveals skeletal site specificity and facilitates the identification of novel loci in the genetic regulation of bone mass attainment.

Heritability of bone mineral density (BMD) varies across skeletal sites, reflecting different relative contributions of genetic and environmental influences. To quantify the degree to which common genetic variants tag and environmental factors influence BMD, at different sites, we estimated the genetic (rg) and residual (re) correlations between BMD measured at the upper limbs (UL-BMD), lower limbs (LL-BMD) and skull (SK-BMD), using total-body DXA scans of ∼ 4,890 participants recruited by the Avon Longitudinal Study of Parents and their Children (ALSPAC). Point estimates of rg indicated that appendicular sites have a greater proportion of shared genetic architecture (LL-/UL-BMD rg = 0.78) between them, than with the skull (UL-/SK-BMD rg = 0.58 and LL-/SK-BMD rg = 0.43). Likewise, the residual correlation between BMD at appendicular sites (r(e) = 0.55) was higher than the residual correlation between SK-BMD and BMD at appendicular sites (r(e) = 0.20-0.24). To explore the basis for the observed differences in rg and re, genome-wide association meta-analyses were performed (n ∼ 9,395), combining data from ALSPAC and the Generation R Study identifying 15 independent signals from 13 loci associated at genome-wide significant level across different skeletal regions. Results suggested that previously identified BMD-associated variants may exert site-specific effects (i.e. differ in the strength of their association and magnitude of effect across different skeletal sites). In particular, variants at CPED1 exerted a larger influence on SK-BMD and UL-BMD when compared to LL-BMD (P = 2.01 × 10(-37)), whilst variants at WNT16 influenced UL-BMD to a greater degree when compared to SK- and LL-BMD (P = 2.31 × 10(-14)). In addition, we report a novel association between RIN3 (previously associated with Paget's disease) and LL-BMD (rs754388: ß = 0.13, SE = 0.02, P = 1.4 × 10(-10)). Our results suggest that BMD at different skeletal sites is under a mixture of shared and specific genetic and environmental influences. Allowing for these differences by performing genome-wide association at different skeletal sites may help uncover new genetic influences on BMD.

The consummatory origins of visually guided reaching in human infants: a dynamic integration of whole-body and upper-limb movements.

Reaching-to-eat (skilled reaching) is a natural behaviour that involves reaching for, grasping and withdrawing a target to be placed into the mouth for eating. It is an action performed daily by adults and is among the first complex behaviours to develop in infants. During development, visually guided reaching becomes increasingly refined to the point that grasping of small objects with precision grips of the digits occurs at about one year of age. Integration of the hand, upper-limbs, and whole body are required for successful reaching, but the ontogeny of this integration has not been described. The present longitudinal study used Laban Movement Analysis, a behavioural descriptive method, to investigate the developmental progression of the use and integration of axial, proximal, and distal movements performed during visually guided reaching. Four infants (from 7 to 40 weeks age) were presented with graspable objects (toys or food items). The first prereaching stage was associated with activation of mouth, limb, and hand movements to a visually presented target. Next, reaching attempts consisted of first, the advancement of the head with an opening mouth and then with the head, trunk and opening mouth. Eventually, the axial movements gave way to the refined action of one upper-limb supported by axial adjustments. These findings are discussed in relation to the biological objective of reaching, the evolutionary origins of reaching, and the decomposition of reaching after neurological injury.

Cross- and triple-ratios of human body parts during development.

Recently developed landmark-based geometric morphometry has been used to depict the morphological development of organisms. In geometry, four landmarks can be mapped to any other four by Möbius transformations, if the cross-ratio of the landmarks is invariant and vice versa. To geometrically analyze the morphological development of the human body, we examined the cross-ratio of three consecutive body parts that are segmented by four landmarks in their configuration. Moreover, we introduced the triple-ratio of five landmarks that segments four consecutive parts (e.g., the shoulder, upper arm, forearm, and hand) and examined their growth patterns. The cross- and triple-ratios of the upper limb and shoulder girdle in fetuses were constant when biomechanical landmarks were used, although the cross-ratio of the upper limb varied when anatomical landmarks were used. The cross-ratios of the lower limbs, trunk, and pelvic girdles in fetuses differed from their corresponding cross-ratios in adults. These results suggest Möbius growth in the fetal upper limb and shoulder girdle but not in the other body parts examined. However, the growth balance of the three contiguous body parts was represented by the developmental change in the cross-ratio. Therefore, the cross- and triple-ratios may be applicable for simple but significant assessments of growth balance or proportion of the body parts.

Upper extremity injuries in the adolescent athlete.

There has been a significant increase in youth sports participation and athletic activities over the past 3 decades. With the increase in participation, there has been a commensurate rise in the number of sports-related injuries. A majority of these injuries are due to overuse as athletes frequently compete in multiple sports with year round competition and training. As higher demands are placed on these young athletes, the likelihood of injury during and individual's playing career continues to increase. This review will focus on both overuse and traumatic injuries of the upper extremity in the adolescent athlete. A significant emphasis will be placed on the evaluation and management of soft tissue and bony injuries in the overhead throwing athlete. The review will conclude with a discussion on common wrist and hand injuries seen in this population.

Índices antropométricos de proporcionalidad corporal de jugadores cadetes y juveniles de rugby / Anthropometric indexes of corporal proportionality of under-16 and under-18 rugby players

La mayoría de los deportes se caracterizan por un patrón cineantropométrico determinado, considerado óptimo para el máximo rendimiento deportivo. No obstante, en los deportes de equipo, como es el rugby, la definición de este patrón es difícil de realizar. La especialización por puestos conduce a la identificación de características antropométricas y fisiológicas específicas, según las diferentes posiciones de juego, que son importantes para el rendimiento óptimo. Esto distingue al rugby de otros deportes dónde los datos morfofuncionales homogéneos son más comunes. El objetivo del presente estudio era establecer según las diferentes edades y los distintos puestos los índices antropométricos de proporcionalidad corporal de una población masculina de jugadores de rugby juveniles y cadetes de Andalucía. Se evaluaron a 32 jugadores de rugby, divididos en dos categorías, cadetes (17) y juveniles (15). La obtención de los datos se hizo según el protocolo de la ISAK. Las mediciones se realizaron durante la fase de competición 2004/2005. Los índices antropométricos de proporcionalidad corporal varían ampliamente de los cadetes a los juveniles, principalmente la longitud relativa de la extremidad inferior, el índice córmico, el índice esquelético y el índice acromio iliaco. Los delanteros, tanto cadetes como juveniles, coinciden en la longitud relativa de la extremidad superior, en el índice intermembral, en el índice córmico y en la envergadura relativa. A su vez los tres cuartos, cadetes y juveniles, concuerdan en la longitud relativa de la extremidad superior, en la longitud relativa de la extremidad inferior y en la envergadura relativa. Dentro de los subgrupos la 2ª línea es la que presenta menor variabilidad de una categoría a la otra

Most sports are characterized by a specific kinanthropometric pattern, which is considered optimum to achieve maximum sports performance. Neverthless, in team sports, like rugby, the characterization of this pattern is difficult. The specialization for positions leads to the identification of specific anthropometric and physiologic characteristics that are important for the optimum performance. The objective of the present study was to establish, according to ages and playing positions, the anthropometric index of body proportionality of male population of Andalusian rugby players under-16 and under –18. Thirty-two rugby players were evaluated, divided into two categories, under –16 (17 subjects) and under –18 (15 subjects). The data collection was made according to the ISAK protocol. The measurement were carried out during the 2004/2005 competition season. The anthropometric indexes of body proportionality widely vary between the under –16 and under –18 groups, specifically with regards to the relative longitude of the inferior extremity, the córmico index, the skeletal index and the acromio-iliac index. The forwards, for both the under –16 and under –18 groups, coincide in the relative longitude of the superior extremity, the intermembral index, the córmico index and the relative span. The backs, for both the under –16 and under –18 groups, coincide in the relative longitude of the superior extremity, the relative longitude of the inferior extremity and the relative span. Within the subgroups, the locks show the least variability

Multiplier method for prediction of adult height in patients with achondroplasia.

To date, the only way to predict adult height in achondroplastic dwarves has been to consult a growth chart. The purpose of this study was to ascertain whether the multiplier method of predicting adult height at skeletal maturity in healthy persons can be applied to persons with achondroplasia. Previous studies have shown that the multiplier method can be applied to lower limb length, upper limb length, total height, foot length, and foot height. It is therefore reasonable to suggest that the growth pattern for total height in achondroplastic dwarves might also be characterized by a multiplier. Total height multipliers for achondroplastic dwarves ("achondroplasia height multipliers") were calculated from two separate databases by dividing height at maturity by height at each respective age for both genders. Little variability was found among multipliers for each age and among multipliers calculated from different databases. Upper torso (sitting height) multipliers and lower limb multipliers were also derived for achondroplastic dwarves. Lower limb and total height growth rates were slower in achondroplastic dwarves compared with healthy persons. However, sitting height multipliers for achondroplastic dwarves were closely related to sitting height multipliers for healthy persons. Because these findings showed that the multiplier values were independent of population and percentile, the multiplier method may be a valid method for quickly predicting height at any age for achondroplastic dwarves.