Application of MRI of the wrist for age determination in international U-17 soccer competitions.
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BACKGROUND: To guarantee equal chances for different age groups, age-related tournaments for male and female players have been established in soccer. However, as registration at birth is not compulsory in some countries, other methods of age determination are needed to prevent participation in the incorrect age group. OBJECTIVES: To evaluate the age of soccer players of international U-17 competitions from the degree of fusion of the distal radius and to compare the findings with an age-related normative population. METHODS: MRI scans of the wrist of a representative sample of 189 players from four U-17 competitions (FIFA U-17 World Cups 2003 and 2005, and Asian (AFC) U-17 championships 2004 and 2006) were analysed using a previously published grading system. RESULTS: Because of different regulations, all players in the AFC U-17 championships were younger than 17 years, whereas 71% of the players in the FIFA U-17 World Cup competitions were 17 years old. The distal radius of 15% of players from the AFC U-17 tournaments and 27% of the players from the FIFA U-17 tournaments were graded as completely fused on the MRI scans, which is a substantially higher percentage than in the respective age groups of a previously published normative population of soccer players. Furthermore, in contrast with the normative population, no significant correlation between the age category and the fusion grading (r = 0.13) was observed in U-17 players. CONCLUSION: From the MRI results, U-17 soccer players seem to be more mature than a normative population of the same age category. However, the lack of correlation between age category and degree of fusion in U-17 players supports the suspicion that the age stated in the official documents of the U-17 players examined might not be correct in all cases. (+info)
Automatic bone age assessment for young children from newborn to 7-year-old using carpal bones.
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A computer-aided-diagnosis (CAD) method has been previously developed based on features extracted from phalangeal regions of interest (ROI) in a digital hand atlas, which can assess bone age of children from ages 7 to 18 accurately. Therefore, in order to assess the bone age of children in younger ages, the inclusion of carpal bones is necessary. However, due to various factors including the uncertain number of bones appearing, non-uniformity of soft tissue, low contrast between the bony structure and soft tissue, automatic segmentation and identification of carpal bone boundaries is an extremely challenging task. Past research works on carpal bone segmentation were performed utilizing dynamic thresholding. However, due to the limitation of the segmentation algorithm, carpal bones have not been taken into consideration in the bone age assessment procedure. In this paper, we developed and implemented a knowledge-based method for fully automatic carpal bone segmentation and morphological feature analysis. Fuzzy classification was then used to assess the bone age based on the selected features. This method has been successfully applied on all cases in which carpal bones have not overlapped. CAD results of total about 205 cases from the digital hand atlas were evaluated against subject chronological age as well as readings of two radiologists. It was found that the carpal ROI provides reliable information in determining the bone age for young children from newborn to 7-year-old. (+info)
Bone age assessment of children using a digital hand atlas.
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We have developed an automated method to assess bone age of children using a digital hand atlas. The hand atlas consists of two components. The first component is a database which is comprised of a collection of 1400 digitized left hand radiographs from evenly distributed normally developed children of Caucasian (CA), Asian (AS), African-American (AA) and Hispanic (HI) origin, male (M) and female (F), ranged from 1- to 18-year-old; and relevant patient demographic data along with pediatric radiologists' readings of each radiograph. This data is separate into eight categories: CAM, CAF, AAM, AAF, HIM, HIF, ASM, and ASF. In addition, CAM, AAM, HIM, and ASM are combined as one male category; and CAF, AAF, HIF, and ASF are combined as one female category. The male and female are further combined as the F & M category. The second component is a computer-assisted diagnosis (CAD) module to assess a child bone age based on the collected data. The CAD method is derived from features extracted from seven regions of interest (ROIs): the carpal bone ROI, and six phanlangeal PROIs. The PROIs are six areas including the distal and middle regions of three middle fingers. These features were used to train the 11 category fuzzy classifiers: one for each race and gender, one for the female, one male, and one F & M, to assess the bone age of a child. The digital hand atlas is being integrated with a PACS for validation of clinical use. (+info)
The shifting baseline of northern fur seal ecology in the northeast Pacific Ocean.
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Historical data provide a baseline against which to judge the significance of recent ecological shifts and guide conservation strategies, especially for species decimated by pre-20th century harvesting. Northern fur seals (NFS; Callorhinus ursinus) are a common pinniped species in archaeological sites from southern California to the Aleutian Islands, yet today they breed almost exclusively on offshore islands at high latitudes. Harvest profiles from archaeological sites contain many unweaned pups, confirming the presence of temperate-latitude breeding colonies in California, the Pacific Northwest, and the eastern Aleutian Islands. Isotopic results suggest that prehistoric NFS fed offshore across their entire range, that California populations were distinct from populations to the north, and that populations breeding at temperate latitudes in the past used a different reproductive strategy than modern populations. The extinction of temperate-latitude breeding populations was asynchronous geographically. In southern California, the Pacific Northwest, and the eastern Aleutians, NFS remained abundant in the archaeological record up to the historical period approximately 200 years B.P.; thus their regional collapse is plausibly attributed to historical hunting or some other anthropogenic ecosystem disturbance. In contrast, NFS populations in central and northern California collapsed at approximately 800 years B.P., long before European contact. The relative roles of human hunting versus climatic factors in explaining this ecological shift are unclear, as more paleoclimate information is needed from the coastal zone. (+info)
Computerized geometric features of carpal bone for bone age estimation.
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BACKGROUND: Bone age development is one of the significant indicators depicting the growth status of children. However, bone age assessment is an heuristic and tedious work for pediatricians. We developed a computerized bone age estimation system based on the analysis of geometric features of carpal bones. METHODS: The geometric features of carpals were extracted and analyzed to judge the bone age of children by computerized shape and area description. Four classifiers, linear, nearest neighbor, back-propagation neural network, and radial basis function neural network, were adopted to categorize bone age. Principal component and discriminate analyses were employed to improve assorting accuracy. RESULTS: The hand X-ray films of 465 boys and 444 girls served as our database. The features were extracted from carpal bone images, including shape, area, and sequence. The proposed normalization area ratio method was effective in bone age classification by simulation. Besides, features statistics showed similar results between the standard of the Greulich and Pyle atlas and our database. CONCLUSIONS: The bone area has a higher discriminating power to judge bone age. The ossification sequence of trapezium and trapezoid bones between Taiwanese and the atlas of the GP method is quite different. These results also indicate that carpal bone assessment with classification of neural networks can be correct and practical. (+info)
Height reduction in 539 tall girls treated with three different dosages of ethinyloestradiol.
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During the period 1970 to 1985, 539 constitutionally tall girls were treated with ethinyloestradiol in varying dosages to reduce final height. They all had a predicted final height above 181 cm (greater than +2.5 SD). The girls were all healthy and were treated with three different dosages of ethinyloestradiol. Throughout these 15 years recommended treatment regimens changed, and the treatments described followed these guidelines. Girls in group 1 (n = 263) were treated with 0.5 mg of ethinyloestradiol, group 2 (n = 178) with 0.25 mg, and group 3 (n = 98) with 0.1 mg. The total mean (SEM) reduction of final height was 5.9 (0.2), 5.3 (0.1), and 4.4 (0.2) cm when treated with 0.5, 0.25, and 0.1 mg respectively. Group 1 was treated for 2.02 (0.03) years and group 2 and 3 for 1.85 (0.04) and 1.63 (0.05) years respectively. When expressed in relation to the treatment period the reduction of final height was 3.0 (0.1), 3.1 (0.1), and 2.9 (0.2) cm/year of treatment respectively. All the girls were treated with ethinyloestradiol as a daily single dose, while progestogen was given daily the first 10 days of every month. In conclusion we found that a daily dose of ethinyloestradiol 0.1 mg for about 20 months is sufficient to reduce final height. We recommend starting treatment at a bone age of about 12 years. (+info)
Heritability of a skeletal biomarker of biological aging.
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Changes in the skeletal system, which include age-related bone and joint remodeling, can potentially be used as a biomarker of biological aging. The aim of the present study was to investigate the extent and mode of inheritance of skeletal biomarker of biological aging-osseographic score (OSS), in a large sample of ethnically homogeneous pedigrees. The investigated cohort comprised 359 Chuvashian families and included 787 men aged 18-89 years (mean 46.9) and 723 women aged 18-90 years (mean 48.5). The TOSS - transformed OSS standardized in 5-year age groups for each sex, was analyzed as a BA index. We evaluated familial correlations and performed segregation analysis. Results of our study suggest the familial aggregations of TOSS variation in the Chuvashian pedigrees. In a segregation analysis we found a significant major gene (MG) effect in the individual's TOSS with a dominant most parsimonious model (H(2) = 0.32). Genetic factors (MG genotypes) explained 47% of the residual OSS variance after age adjustment and after including sex-genotype interaction, they explained 52% of the residual variance. Results of our study also indicated that the inherited difference in the skeletal aging pattern in men lies mostly in the rate of aging, but in women in the age of the onset of the period of visible skeletal changes. (+info)
Morphological study on quadruplets by cephalometric and model analyses.
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Clarifying the genetic factors involved in maxillofacial growth and development is very important in orthodontic treatment planning and prognosis. However, few dental studies have examined multiple births. The present orthodontic evaluation was conducted using orthodontic data from a set of quadruplets. Orthodontic evaluation was performed on a set of quadruplets (1 girl and 3 boys) aged 9 years and 7 months at the initial visit. Although all 4 children weighed only about 1,400 g each at birth, height and body weight subsequently normalized. Mean skeletal age of the quadruplets was 10 years and 2 months, about 6 months ahead of their calendar age. In all 4 children, facial profile was mostly symmetrical and convex. Intraoral findings showed a Hellman's dental age of IIIA, together with spacing of the upper anterior teeth. Both overbite and overjet were 5-7 mm, and mesial step of the terminal plane was noted. Model analysis showed that tooth materials were on the large side, while arch width was narrow. Cephalometric analysis revealed that the ANB of the first- and fourth-born children was 6 degrees , and skeletal maxillary protrusion due to mandibular retrusion was diagnosed. The second- and thirdborn children exhibited no marked skeletal abnormalities. (+info)