OBJECTIVES: Using prenatally fixed dermatoglyphics features as markers of prenatal sex development is limited due to insufficient knowledge on their sex differences. This study aims to examine more thoroughly sex differences in radioulnar contrasts. METHODS: Fingerprints of 360 females and 331 males from four samples of different ethnic backgrounds (Czechs, Slovaks, Vietnamese and Lusatian Sorbs) were studied. On both hands, finger ridge counts were recorded, and all possible radioulnar contrasts were computed as a difference between ridge count at a radial position minus ridge count at a respective ulnar position on the hand. Radioulnar contrasts with population-congruent and numerically large dimorphism were selected and the dimorphism of the selected radioulnar contrasts was then tested using nonparametric analysis of variance. RESULTS: Greater dimorphism of radioulnar contrasts occurred on the right hand than on the left hand. Population congruent direction and relatively strong dimorphism (Cohen's d greater than 0.3) was found in six radioulnar contrasts on the right hand, all of which involved the radial ridge count of the 2nd finger. Of these, the highest average dimorphism was observed for the difference between the radial ridge count of the 2nd finger and the ulnar ridge count of the 4th finger (2r4u contrast), where the average effect size from all four population samples was comparable to a published average effect size of the 2D:4D finger length ratio. CONCLUSION: We propose that 2r4u contrast of ridge counts could serve as a marker of prenatal sexual development targeting a temporally narrow developmental window.
- MeSH
- biologické markery MeSH
- dermatoglyfika * MeSH
- etnicita MeSH
- lidé MeSH
- pohlavní dimorfismus * MeSH
- prsty ruky anatomie a histologie MeSH
- sexuální vývoj MeSH
- těhotenství MeSH
- vitaminy MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- těhotenství MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Introduction: Reports on the use of computer-assisted trauma surgery of comminuted scapula fracture are still quite rare. In this article, we present a case of comminuted scapula fracture, the surgical reconstruction of which was pre-operatively planned using a complex software solution. Materials and methods: For surgical planning of the fracture, we used the TraumaTech software facilitating virtual reconstruction (both manual and automatic), surgery planning, design of the implant, planning of screw placement and lengths, and production of a 3D print model of the fracture and the implant. The software also supported ordering such custom-made plate from a plate producer who was capable of fast and precise production of the plate. Results: The surgery using the custom-ordered plate was successful. The actual used screw lengths did not differ from the planned ones by more than 2 mm. One year after the surgery, the patient was capable of more demanding activities and doing sports activities. Conclusion: This approach provides a great way to prevent complications of the surgery and to shorten its duration. To the best of our knowledge, this is the first description of the treatment of a scapula comminuted fracture utilizing computer-assisted preoperative planning.
- Publikační typ
- kazuistiky MeSH
A variety of models are available for the estimation of parameters of the human growth curve. Several have been widely and successfully used with longitudinal data that are reasonably complete. On the other hand, the modeling of data for a limited number of observation points is problematic and requires the interpolation of the interval between points and often an extrapolation of the growth trajectory beyond the range of empirical limits (prediction). This study tested a new approach for fitting a relatively limited number of longitudinal data using the normal variation of human empirical growth curves. First, functional principal components analysis was done for curve phase and amplitude using complete and dense data sets for a reference sample (Brno Growth Study). Subsequently, artificial curves were generated with a combination of 12 of the principal components and applied for fitting to the newly analyzed data with the Levenberg-Marquardt optimization algorithm. The approach was tested on seven 5-points/year longitudinal data samples of adolescents extracted from the reference sample. The samples differed in their distance from the mean age at peak velocity for the sample and were tested by a permutation leave-one-out approach. The results indicated the potential of this method for growth modeling as a user-friendly application for practical applications in pediatrics, auxology and youth sport.
- Publikační typ
- časopisecké články MeSH
Sledování individuálního růstu je v pediatrické praxi vyžadováno denně a často je doprovázeno potřebou podrobnějších analýz. Analýzu lidského růstu potřebují také sportovní antropologové a výzkumníci v oblasti biologie člověka. Přínosem by tedy byla pokročilá a zároveň snadno použitelná a bezplatná aplikace, která by pediatrům, auxologům a výzkumným pracovníkům v oblasti biologie člověka umožňovala provádět hloubkovou analýzu postnatálního růstu. Aplikace GROWTH byla vyvinuta na základě pochopení biologických procesů lidského růstu a matematických přístupů, které poskytují nejvhodnější model pro individuální (longitudinální) empirická data. Aplikace je navržena tak, aby ji bylo možné používat v každodenní pediatrické praxi. Poskytuje lékařům nástroje pro sledování růstu, předpovídání dosažené výšky a diagnostiku patologických růstových vzorců. Pokročilá analýza zahrnuje odhad časování hlavních růstových milníků. Současná verze je vyvrcholením několikastupňového vývoje aplikace a je založena na metodě FPCA (funkční analýza hlavních komponent) s numerickou optimalizací. Výstupní parametry jsou snadno použitelné a zobrazují se numericky i graficky.
Monitoring of individual growth is required on daily basis in paediatric practice, often accompanied by need for more in-depth analyses. Sports anthropologists and researchers in the fi eld of human biology also need to analyze human growth. To allow clinicians and researchers to monitor human growth and analyze it in advanced manner, easy-to-use free application would be beneficial. The application, GROWTH, was developed based on an understanding of the biological processes of human growth and mathematical approaches that provide the most appropriate model for individual (longitudinal) empirical data. The application is designed to be used in daily paediatric practice. It provides clinicians with tools to monitor growth, predict attained height and diagnose pathological growth patterns. Advanced analysis includes the timing of major growth milestones. The current version is the culmination of a multi-stage development of the application and is based on Functional Principal Components Analysis method with numerical optimization. The output parameters are easy to use and are displayed both numerically and graphically.
A model-based radiostereometric analysis (MBRSA) is a method for precise measurement of prosthesis migration, which does not require marking the implant with tantalum beads. Instead, the prosthesis pose is typically recovered using a feature-based 2D-3D registration of its virtual model into a stereo pair of radiographs. In this study, we evaluate a novel intensity-based formulation of previously published nonoverlapping area (NOA) approach. The registration is capable of performing with both binary radiographic segmentations and nonsegmented X-ray images. In contrast with the feature-based version, it is capable of dealing with unreliable parts of prosthesis. As the straightforward formulation allows efficient acceleration using modern graphics adapters, it is possible to involve precise high-poly virtual models. Moreover, in case of binary segmentations, the nonoverlapping area is simply interpretable and useful for indicating the accuracy of the registration outcome. In silico and phantom evaluations were performed using a cementless Zweymüller femoral stem and its reverse engineered (RE) model. For initial pose estimates with difference from the ground-truth limited to ±4 mm and ±4°, respectively, the mean absolute translational error was not higher than 0.042 ± 0.035 mm. The error in rotation around the proximodistal axis was 0.181 ± 0.265°, and the error for the remaining axes was not higher than 0.035 ± 0.037°.
- MeSH
- analýza selhání vybavení metody MeSH
- fantomy radiodiagnostické MeSH
- femur diagnostické zobrazování MeSH
- kyčelní protézy MeSH
- lidé MeSH
- počítačové zpracování obrazu metody MeSH
- radiostereometrická analýza metody MeSH
- tantal MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Objectives: At present, medical thermal imaging is still considered a mere qualitative tool enabling us to distinguish between but lacking the ability to quantify the physiological and nonphysiological states of the body. Such a capability would, however, facilitate solving the problem of medical quantification, whose presence currently manifests itself within the entire healthcare system. Methods: A generally applicable method to enhance captured 3D spatial data carrying temperature-related information is presented; in this context, all equations required for other data fusions are derived. The method can be utilized for high-density point clouds or detailed meshes at a high resolution but is conveniently usable in large objects with sparse points. Results: The benefits of the approach are experimentally demonstrated on 3D thermal scans of injured subjects. We obtained diagnostic information inaccessible via traditional methods. Conclusion: Using a 3D model and thermal image data fusion allows the quantification of inflammation, facilitating more precise injury and illness diagnostics or monitoring. The technique offers a wide application potential in medicine and multiple technological domains, including electrical and mechanical engineering.
OBJECTIVES: The second-to-fourth digit ratio (2D:4D ratio) can be assumed a valid indicator of sexual differentiation, provided that it is stable once it develops, or eventual changes remain uniform in a respective cohort throughout ontogenesis. The main goal of this study was to determine whether the metacarpal 2M:4M and the digit 2D:4D ratio change during the period of pubertal/adolescent growth. MATERIALS AND METHODS: The metacarpals and digits were measured on radiographs of left hands in the sample of 328 individuals (96 pairs of male and 68 pairs of female twins) from the Wrocław Longitudinal Study of Twins (1967-1983). Five consecutive annual measurements were done for each individual within a 4-year-interval somewhere between 7 and 18 years of age. Age-related changes in both ratios were studied using a set of mixed-effects linear models. Three types of correlation coefficients were used for assessment of stability between repeated measurements at different ages. RESULTS: An overall decrease in the average 2M:4M ratio was observed, attributable to a much larger extent to males than to females. On the contrary, a slight overall increase in the average 2D:4D ratio was observed, attributable to a much larger extent to females than to males. The rank order of the ratios remained highly stable within the monitored period (the correlation coefficient mostly ranged between 0.85 and 0.95). In spite of these findings, we recorded significant intraindividual changes in both ratios. In some individuals the 2D:4D ratio can undergo changes comparable to average sex differences and much higher than average age-related changes. DISCUSSION: Relatively slight overall changes in digit ratio in puberty and adolescence themselves are not inconsistent with the use of the 2D:4D ratio as an indirect marker of prenatal sexual differentiation. Nevertheless, individual changes in the ratios varied substantially in this study and differed from the average trends. Future studies should focus on the nature of interindividual developmental differences in the digit and metacarpal ratios.
- MeSH
- antropologie fyzická MeSH
- antropometrie MeSH
- dítě MeSH
- dvojčata MeSH
- lidé MeSH
- longitudinální studie MeSH
- mladiství MeSH
- pohlavní dimorfismus MeSH
- pohlavní dospělost MeSH
- prsty ruky anatomie a histologie MeSH
- puberta fyziologie MeSH
- Check Tag
- dítě MeSH
- lidé MeSH
- mladiství MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
