Bone age assessment based on different MRI modalities of the proximal humerus epiphysis: the comparisons of T1WI, T2WI, and PDWI.

Bone age assessment (BAA) is crucial in various fields, including legal proceedings, athletic competitions, and clinical medicine. However, the use of X-ray methods for age estimation without medical indication is subject to ethical debate, especially in forensic and athletic fields. The application of magnetic resonance imaging (MRI) with non-ionizing radiation can overcome this limitation in BAA. This study aimed to compare the application value of several MRI modalities of proximal humeral in BAA. A total of 468 patients with shoulder MRIs were retrospectively collected from a Chinese Han population aged 12-30 years (259 males and 209 females) for training and testing, including T1 weighted MRI (T1WI), T2 weighted MRI (T2WI), and Proton density weighted MRI (PDWI). Optimal regression models were established for age estimation, yielding mean absolute error (MAE) values below 2.0 years. The MAE values of T1WI were the lowest, with 1.700 years in males and 1.798 years in females. The area under the curve (AUC) and accuracy values of different MRI modalities of 16-year and 18-year thresholds were all around 0.9. For the 18-year threshold, T1WI outperformed T2WI and PDWI. In conclusion, the three MRI modalities of the proximal humerus can serve as reliable indicators for age assessment, while the T1WI performed better in age assessment and classification.

Ultrasonographic assessment of ossification of the distal radial epiphysis for estimating forensic age.

Since forensic age estimation is not a valid medical indication, research on the use of nonionizing methods is increasing. Ultrasonography is a radiological approach that protects patients from radiation exposure and offers special convenience to them. In this study, ultrasonography was used for age estimation by investigating the degree of ossification of the distal radial epiphysis. Its applicability on the Turkish population was investigated. The left wrist of 688 (322 males, 366 females) patients between the ages of 9 and 25 years was prospectively evaluated by ultrasonography. The intra- and interobserver reliabilities in evaluating the distal radial epiphysis and Cohen's kappa statistics show that the interobserver error was very low, and the kappa value was found to be 0.919. Stage 3 and 4 ossification of the distal radial epiphysis was first detected at age 14.3 and 15.3 years in males and 12.7 and 14.8 years in females, respectively. The data obtained may help determine legally critical age limits of 14 and 15. Although it does not seem useful for the age of 18, ultrasonography may be recommended in selected cases as a fast, inexpensive, frequently reproducible radiological method without concern about radiation and without a predictable health risk.

Technical note: utilization of 3D-rendering for CT evaluation of extremitas sternalis claviculae within medical age assessment practice.

According to the acknowledged recommendations of the multidisciplinary "Study Group on Forensic Age Diagnostics," the indicator "medial clavicular ossification" carries the potential of delivering decisive evidence to proof age majority "beyond reasonable doubt" regarding age-disputed individuals within legal procedures. Yet, sternoclavicular thin-slice computed tomography, representing its preferred imaging modality, not rarely exhibits peculiar morphologies of the site, sometimes difficult to understand from the usually obtained, axial sections together with coronal reformations. Because of that, we utilized 3D-rendering of acquired CT data in 224 cases with the purpose to gain additional visualization of certain questionable appearances. Concerning reliable classification of medial clavicular ossification in line with the typologies of Schmeling et al. and Kellinghaus et al., it is concluded that such means of illustration contribute to recognition of polygonal or irregular, epiphyseal formations including the not-assessable shape variant "multiple, medial, secondary ossification centres" and of calcification of the articular capsule.

Applicability of T1-weighted MRI in the assessment of forensic age based on the epiphyseal closure of the humeral head.

This work investigates the value of magnetic resonance imaging analysis of proximal epiphyseal fusion in research examining the growth and development of the humerus and its potential utility in establishing forensic age estimation. In this study, 428 proximal humeral epiphyses (patient age, 12-30 years) were evaluated with T1-weighted turbo spin echo (T1 TSE) sequences in coronal oblique orientation on shoulder MRI images. A scoring system was created following a combination of the Schmeling and Kellinghaus methods. Spearman's rank correlation analysis revealed a significant positive relationship between age and ossification stage of the proximal humeral epiphysis (all subjects: rho = 0.664, p < 0.001; males: 0.631, p < 0.001; females: rho = 0.651, p < 0.001). The intra- and inter-observer reliability assessed using Cohen's kappa statistic was κ = 0.898 and κ = 0.828, respectively. The earliest age of epiphysis closure was 17 years for females and 18 years for males. MRI of the proximal humeral epiphysis can be considered advantageous for forensic age estimation of living individuals in a variety of situations, ranging from monitoring public health to estimating the age of illegal immigrants/asylum seekers, minors engaged in criminal activities, and illegal participants in competitive sports, without the danger of radiation exposure.

Error rates for unvalidated medical age assessment procedures.

During 2014-2015, Sweden received asylum applications from more than 240,000 people, of which more than 40,000 were termed unaccompanied minors. In a large number of cases, claims by asylum seekers of being below 18 years were not trusted by Swedish authorities. To handle the situation, the Swedish national board of forensic medicine (Rättsmedicinalverket, RMV) was assigned by the government to create a centralized system for medical age assessments. RMV introduced a procedure including two biological age indicators; x-ray of the third molars and magnetic resonance imaging of the distal femoral epiphysis. In 2017, a total of 9617 males and 337 females were subjected to this procedure. No validation study for the procedure was however published, and the observed number of cases with different maturity combinations in teeth and femur were unexpected given the claims originally made by RMV. We present a general stochastic model enabling us to study which combinations of age indicator model parameters and age population profiles are consistent with the observed 2017 data for males. We find that, contrary to some RMV claims, maturity of the femur, as observed by RMV, appears on average well before maturity of teeth. According to our estimates, approximately 15% of the tested males were children. These children had an approximate 33% risk of being classified as adults. The corresponding risk for an adult to be misclassified as a child was approximately 7%. We determine uncertainties and ranges of estimates under reasonable perturbations of the prior.

An Abbreviated Scale for the Assessment of Skeletal Bone Age Using Radiographs of the Knee.

Hand and wrist radiographs are the most common means for estimating skeletal bone age. There is no widely used scale for estimating skeletal bone age using knee radiographs. Do skeletal bone age estimates from knee-maturity scales correlate sufficiently with both chronologic age and estimates from a hand-wrist scale to potentially substitute for estimates from the latter? The authors reviewed the records of 503 patients 6 to 19 years old who had hand and knee radiographs obtained within 30 days of each other. They analyzed radiographs using the O'Connor knee scale (based on 10 maturation markers) and a new, abbreviated version of the O'Connor scale (based on 7 markers). The authors also analyzed radiographs of the hands of boys 12.5 to 16 years old and girls 10 to 16 years old using the shorthand method. Multivariate linear regression was used for analysis. Inter- and intrarater reliabilities were assessed. Skeletal bone age derived from the O'Connor and abbreviated knee scales correlated with chronologic age (adjusted R2=0.88 and 0.90, respectively). Compared with estimates from the hand-wrist scale, estimates were lower by a mean of 0.91 years for boys and 0.38 years for girls when using the O'Connor scale and 0.96 years for boys and 0.52 years for girls when using the abbreviated scale. Inter- and intrarater reliabilities were very good (κ=0.82 and 0.90, respectively) and were substantial at each bony landmark measured. Knee radiographs can be used to estimate skeletal bone age using an abbreviated knee scale. [Orthopedics. 2018; 41(5):e676-e680.].

Assessment of adulthood in the living Spanish population based on ossification of the medial clavicle epiphysis using ultrasound methods.

It is a fact that in recent years requests have greatly increased to obtain estimates of the legal age of undocumented individuals alleged to be minors who have been forced to enter different European Community countries for socioeconomic reasons or due to war. Spain is one of the countries most affected by this illegal immigration because of its proximity to North Africa. Therefore, it has become necessary to develop new standards which help provide a response to the demands of the justice administration. In recent years, the Superior Justice Court has rejected several pieces of expert evidence on the grounds that the age intervals therein were not sufficiently reliable and that the radiographic techniques used to determine age were invasive, potentially causing harm to the alleged minor. These sentences have caused interest in this field of work to increase within the scientific community. As a result, in order to improve age predictions and, above all, reduce minors' exposure to radiation, this study was created for completion on the Spanish population, using the ultrasound scan as a diagnostic technique. Used as a study sample were the ultrasound images of the proximal sternal epiphysis of the clavicle among 221 individuals of both sexes, of ages ranging from 5 to 30 years. All of the images were classified into 4 stages of fusion, in accordance with the development of metaphyseal closure proposed by Schulz et al. in 2008. The results show differences among the 4 proposed groups for each of the stages of fusion, with the results found in Stage II being especially important because, for both sexes, they would imply that the patient studied has reached an age of over 18 years, which is the legal age of adulthood in Spain, as established by the Spanish Constitution of 1978. Though further research is still recommended, these results, coupled with the use of ultrasound as a non-invasive diagnostic technique, could help solve some of the problems currently arising in justice courts.

Magnetic resonance imaging-based evaluation of ossification of the medial clavicular epiphysis in forensic age assessment.

Evaluation of the degree of ossification of the medial clavicular epiphysis plays a crucial role in determining with an adequate degree of probability whether legally relevant age boundaries after the age of 17 have been crossed. In view of the need to avoid unnecessary radiation exposure, establishing non-X-ray methods for investigating the clavicle has long been a key objective in forensic age assessment research. Based on magnetic resonance imaging examinations in a large sample of healthy subjects, the current study for the first time presents statistical measures which allow inferences to be drawn for forensic age assessment in both sexes. We undertook a prospective study of a reference sample of 334 female and 335 male German volunteers aged from 12 to 24 using a 3-T MRI scanner. A 3D FFE (fast field echo) T1-weighted sequence with fat saturation was acquired. To stage ossification of the medial clavicular epiphysis, we used the clavicular ossification staging systems described by Schmeling et al. and Kellinghaus et al. Ossification stage IIIc offers a means in both sexes of demonstrating that the age of 18 has been attained prior to complete ossification of the epiphyseal plate. In both sexes, if a subject has reached ossification stage IV, it can be stated that he or she has attained the age of 21. Magnetic resonance imaging is a valid diagnostic procedure for determining the ossification stage of the medial clavicular epiphysis.

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.

Contribution of magnetic resonance imaging of the wrist and hand to forensic age assessment.

Forensic age estimation of living individuals is a controversial subject because of the imprecision of the available methods which leads to errors. Moreover, young persons are exposed to radiation, without diagnostic or therapeutic advantage. Recently, non-invasive imaging techniques such as magnetic resonance imaging (MRI) have been studied in this context. The aim of this work was to study if the analysis of wrist/hand MRI enabled determination of whether a subject was 18 years old. Two observers retrospectively analyzed metaphyseal-epiphyseal fusion of the distal epiphysis of the radius and the ulna and the base of the first metacarpus in wrist/hand MRI of living people between 9 and 25 years of age. A three-stage scoring system was applied to all epiphyses. Intra- and inter-observer variability was excellent. Staging of the distal radial epiphysis allowed the subjects to be correctly evaluated with regard to the 18-year-old threshold in more than 85 % of cases. Analysis of the radius alone was as good as the analysis of the three epiphyses together. Evaluation of the metaphyseal-epiphyseal fusion of the distal radius in wrist MRI gave good results in forensic age estimation. Wrist MRI could meet ethical expectations with regard to the link between the benefit and risk of practicing radiologic examination on individuals in this context.

A comparison of the simplified olecranon and digital methods of assessment of skeletal maturity during the pubertal growth spurt.

Assessment of skeletal age is important in children's orthopaedics. We compared two simplified methods used in the assessment of skeletal age. Both methods have been described previously with one based on the appearance of the epiphysis at the olecranon and the other on the digital epiphyses. We also investigated the influence of assessor experience on applying these two methods. Our investigation was based on the anteroposterior left hand and lateral elbow radiographs of 44 boys (mean: 14.4; 12.4 to 16.1 ) and 78 girls (mean: 13.0; 11.1 to14.9) obtained during the pubertal growth spurt. A total of nine observers examined the radiographs with the observers assigned to three groups based on their experience (experienced, intermediate and novice). These raters were required to determined skeletal ages twice at six-week intervals. The correlation between the two methods was determined per assessment and per observer groups. Interclass correlation coefficients (ICC) evaluated the reproducibility of the two methods. The overall correlation between the two methods was r = 0.83 for boys and r = 0.84 for girls. The correlation was equal between first and second assessment, and between the observer groups (r ≥ 0.82). There was an equally strong ICC for the assessment effect (ICC ≤ 0.4%) and observer effect (ICC ≤ 3%) for each method. There was no significant (p < 0.05) difference between the levels of experience. The two methods are equally reliable in assessing skeletal maturity. The olecranon method offers detailed information during the pubertal growth spurt, while the digital method is as accurate but less detailed, making it more useful after the pubertal growth spurt once the olecranon has ossified.

The value of sub-stages and thin slices for the assessment of the medial clavicular epiphysis: a prospective multi-center CT study.

The clavicle plays an important role for forensic age estimation in living individuals, particularly with regard to the age of majority. The present prospective study aims to evaluate the age-dependent ossification process of the medial clavicular epiphysis in order to establish the clavicular sub-stages introduced in 2010 as well as the advantages and possibilities of thin-slice computed tomography (CT). For this purpose, 0.6 mm thin-slice CT scans of sternoclavicular joints of 572 bodies aged between 10 and 40 years were evaluated by means of two complementary classification systems: a five-stage system and a sub-staging system for the main stages 2 and 3. Assessment was possible in 493 cases. The results for stages 4 and 5 are in line with previous studies that found the ages of 21 years and 26 years, respectively, as minimum ages for these stages. Sub-stage 3c was first found at the age of 19 years in both sexes, thereby corroborating the value of this sub-stage as to statements about the age of majority. In comparison to other CT studies, stage 3a was first observed ~1 year earlier (16.4 years in males and 15.5 years in females). Stage 2c only occurred in 3 cases. In conclusion, the data corroborate the significance of diagnosing sub-stages as well as the value of thin-slice CT. For forensic practice, the concomitant and complementary use of both classification systems applied in this study can be recommended.

[Automated assessment of developmental levels of epiphysis by support vector machine].

OBJECTIVE: To realize the automated assessment of the levels of epiphysis of distal radius and ulna by support vector machine (SVM). METHODS: The X-ray films of the left wrist joints were taken from 140 teenagers aged from 11 to 19 years old as training samples. The levels of epiphysis of distal radius and ulna were divided into five developmental levels. Each level contained 28 samples. Another 35 cases were selected as independent verifying samples. SVM classification models of the five developmental levels of epiphysis of distal radius and ulna were established. The internal cross validation was made by leave one out cross validation (LOOCV), while the external validation was made by histogram of oriented gradient (HOG), and then the accuracy (PA) of testing results was calculated, respectively. RESULTS: The PA of SVM, LOOCV and HOG of distal radius epiphyseal level were 100%, 78.6%, and 82.8%, respectively; whereas the PA of SVM, LOOCV and HOG of distal ulna epiphyseal level were 100.0%, 80.0% and 88.6%, respectively. CONCLUSION: The SVM-based automatic models of the growth stage of distal ra- dius and ulna appear to have certain feasibility, and may provide a foundation for software development of bone age assessment by forensic medicine.

Tooth mineralization stages as a diagnostic tool for assessment of skeletal maturity.

INTRODUCTION: The objective of this study was to determine whether dental calcification can be used as a first-level diagnostic tool for assessment of skeletal maturity. METHODS: A total of 150 healthy subjects (79 boys, 71 girls; mean age, 12.19 ± 2.03 years; range, 8-16 years) were enrolled in the study. Dental maturity was assessed through the calcification stages from panoramic radiographs of the mandibular canine, the first and second premolars, and the second molar. Determination of skeletal maturity was according to the modified middle phalanx of third finger (MP3) stages method on digital radiographs. RESULTS: Diagnostic ability was evaluated according to the dental maturation stages for each tooth for identification of the MP3 stages and the growth phases (prepubertal, pubertal, postpubertal) using positive likelihood ratios. Dental maturation stage E of the first premolars and the combination of canine stage F, first premolar stage E, second premolar stage E, and second molar stage D (FEED) gave the highest values for identification of the prepubertal growth phase, and stage H of the second molar had the highest value for identification of the postpubertal growth phase. CONCLUSIONS: Dental maturation assessment is only useful for diagnosis of the prepubertal and postpubertal growth phases.

Sonographic assessment of the ossification of the medial clavicular epiphysis in 616 individuals.

Establishing radiation-free imaging methods for the assessment of clavicular ossification in forensic age determination is desirable as it reduces radiation exposure in living individuals. For this purpose the stage of ossification of the right medial clavicular epiphysis was determined prospectively using sonography in 309 male and 307 female healthy volunteers. The classification of stages according to Schulz et al. was used for this purpose. Stage 2 was first noticed at the age of 14.4 years in males, and at the age of 14.1 years in females. Stage 3 was first achieved by males at the age of 17.6 years and by females at the age of 17.4 years. Stage 4 first occurred in males at the age of 19.3 years and at the age of 18.9 years in females. The mean age for stage 1 was 13.6 years. The mean age of stage 2 ranged between 17.3 and 17.6 years. For stage 3 the mean age varied from 20.7 to 21.2 years, and for stage 4 from 23.3 to 23.5 years. It was concluded that sonographically determined stage 4 clavicular ossification provides evidence for the completion of the nineteenth year of life in males and the eighteenth year of life in females. In order to increase the reliability of age determination using this method it is recommended that findings be recorded by at least two experienced independent examiners who then reach a consensus.

Humeral development from neonatal period to skeletal maturity--application in age and sex assessment.

The goal of the present study is to examine cross-sectional information on the growth of the humerus based on the analysis of four measurements, namely, diaphyseal length, transversal diameter of the proximal (metaphyseal) end of the shaft, epicondylar breadth and vertical diameter of the head. This analysis was performed in 181 individuals (90 ♂ and 91 ♀) ranging from birth to 25 years of age and belonging to three documented Western European skeletal collections (Coimbra, Lisbon and St. Bride). After testing the homogeneity of the sample, the existence of sexual differences (Student's t- and Mann-Whitney U-test) and the growth of the variables (polynomial regression) were evaluated. The results showed the presence of sexual differences in epicondylar breadth above 20 years of age and vertical diameter of the head from 15 years of age, thus indicating that these two variables may be of use in determining sex from that age onward. The growth pattern of the variables showed a continuous increase and followed first- and second-degree polynomials. However, growth of the transversal diameter of the proximal end of the shaft followed a fourth-degree polynomial. Strong correlation coefficients were identified between humeral size and age for each of the four metric variables. These results indicate that any of the humeral measurements studied herein is likely to serve as a useful means of estimating sub-adult age in forensic samples.

Digital radiograph of the middle phalanx of the third finger (MP3) region as a tool for skeletal maturity assessment.

OBJECTIVE: To evaluate the reliability of the digital radiograph of the middle phalanx of the third finger (MP3) in skeletal maturity assessment. STUDY DESIGN: Fifty children (24 girls and 26 boys) belonging to the circumpubertal age-group were selected for the study. Two radiographs - lateral cephalogram and digital radiograph of the MP3 region - were taken in each child. Age assessment was based on the changes in shape of the cervical vertebrae and the epiphysis of the middle phalanx of the third finger of the left hand. The radiographs were assessed by three examiners. The inter- and intraexaminer variability were determined by the Wilcoxon rank sign test and the Kruskal-Wallis test and were found to be nonsignificant. Examiner 3 showed the best intraexaminer agreement and was selected to evaluate the radiographs for the entire study. RESULTS: The correlation determined between the MP3 stages and cervical vertebrae maturity index (CVMI) stages, the peak-wise distribution of the MP3 stages, and the correlation between the MP3 stages and the chronological age were found to be highly significant. CONCLUSIONS: Digital radiograph of the MP3 region is definitely a simple, reliable, cost-effective, and time-saving technique for the assessment of skeletal maturity.

The reliability of dental x-ray film in assessment of MP3 stages of the pubertal growth spurt.

The main object of this clinical study is to provide a simple and practical method to assess the pubertal growth spurt stages of a subject by recording MP3 stages with the dental periapical radiograph and the standard dental x-ray machine.

Computer-assisted bone age assessment based on features automatically extracted from a hand radiograph.

This paper presents a computer-aided classification algorithm to assist the radiologist in the bone age assessment of pediatric patients. The classification is based on features automatically extracted from two regions of Computed Radiography (CR) left hand wrist images: phalangeal region of interest (PROI) and carpal bone region of interest (CROI). Due to imprecise nature of the bone age assessment problem, a fuzzy classifier for both regions has been developed. After defining a membership function for each region, features are processed yielding a matrix which maps the set of features to a year of age within the predefined range. The grades of membership are described as membership function values in the interval [0, 1]. A classification rule based on a max-sum operator, processes the matrix assessing the bone age. Since both regions are analyzed independently, two bone age assessments are obtained. They reflect the phalangeal and carpal bones maturity individually. In pathological cases the discrepancy between both assessments may reach as much as 2 yr.

Pitfalls in the assessment of skeletal immaturity: an anthropologic case study.

Nonoperative treatment protocols in adolescent scoliosis require that growth is still occurring. The open iliac apophyses and vertebral ring apophyses are usually considered evidence that growth remains. Studies of adolescent skeletons are not consistent with this view, and one such example is presented. Of clinical importance is that determinant of immaturity should be based on the secondary sexual characteristics, not roentgenographic shadows.