Correlation of age and ossification of the medial clavicular epiphysis using computed tomography

Age estimation based on the metamorphosis of the clavicle end: A test of Falys and Prangle method in two contemporary samples

Upon finding skeletal unidentified remains, four are the questions that must be answered: age, sex, ancestry, and stature. Regarding age estimation, clavicle has received special attention because medial epiphysis is the last epiphysis, among long bones that ossifies. Falys and Prangle proposed a method of age estimation based on three degenerative characteristics-surface topography (TOP), Porosity (POR) and Osteophyte formation (OST)-evaluated on the sternal end of the clavicle according to the descriptions and the illustrations provided in the original article producing satisfactory results. The current study aims to test the applicability of the Falys' and Prangle's method on 174 individuals from two contemporary samples, one from Greece (Cretan osteological Collection and Athens Forensic Anthropology Lab collection) and one from Thailand (Osteological collection in Chiang Mai). Composite scores were calculated, inter and intra- observer error were estimated by kappa statistics and regression equations of the original study were tested in our sample and in subsamples divided by sex and population. The Greek sample gave more accurate estimates compared to the Thai sample. Regressions of known sex gave slightly better results in most cases. When individuals <40 years old were excluded, classification increased for both Thai and Greeks. The results of this pilot study indicate that there are morphological features on the clavicle that are highly correlated with age. Thus, there is a scope of expanding research on the morphological features of the collar bone.

Standards of practice in forensic age estimation with CT of the medial clavicular epiphysis-a systematic review

The AGFAD (Arbeitsgemeinschaft für Forensische Alterdiagnostik, Study Group on Forensic Age Diagnostics) has published several recommendations regarding both technical aspects of computed tomography (CT) of the medial clavicular epiphysis (MCE) and the process of reading and interpreting the CT images for forensic age estimations (FAE). There are, however, no published recommendations regarding CT scan protocols and no dose reference values for CT of the MCE. The objective of this analysis was to assess adherence to AGFAD recommendations among practitioners of FAE and analyse reported dose-relevant CT scan parameters with the objective of helping to establish evidence-based dose reference values for FAE. A systematic literature search was conducted in PubMed and in Google Scholar with specific MeSH terms to identify original research articles on FAE with CT of the MCE from 1997 to 2022. A total of 48 studies were included. Adherence to AGFAD recommendations among practitioners of FAE is high regarding the use of Schmeling main stages (93%), bone window (79%), ≤ 1 mm CT slices (67%), axial/coronal CT images (65%), and Kellinghaus sub-stages (59%). The reporting of CT technique and CT dose-relevant scan parameters is heterogeneous and often incomplete in the current literature. Considering the success achieved by the AGFAD in creating standards of practice of FAE in living subjects, there is potential for the AGFAD to establish standards for radiation protection in FAE as well.

Forensic Age Estimation: A Multifactorial Approach in a Retrospective Population Study

Objectives: The objective of this study was to evaluate the accuracy of forensic age estimation in a German population by combining clavicle and wisdom teeth assessments based on cone beam computed tomography (CT) data. The study aimed to determine the reliability of this approach in predicting biological age. Material and Methods: A total of 161 CT data sets from 120 males and 41 females with known exact ages were evaluated by three raters. The clavicle was assessed according to stages 1-5 (including substages 2a-c and 3a-c), and the Demirjian stage's classification method was used for the wisdom teeth. Inter-class correlation (ICC) was calculated to assess the agreement among the three raters. Additionally, ordinary least square regressions were performed to predict chronological age using the clavicle or one of the four teeth. Finally, age prediction models using multiple indicators were developed. Results: The ICCs ranged from 0.82 for the clavicle to 0.86 and 0.88 for the wisdom teeth. Linear estimation tended to overestimate chronological age, especially in subjects over 18 years old. The clavicle showed the strongest overestimation. Combining age estimation from the clavicle with the upper and lower wisdom teeth improved the predictive power, resulting in a 14% and 15% increase in R² for the upper and lower wisdom teeth, respectively. Adding more than one tooth to the prediction did not improve the predictive power (all ΔR² < 1%). Conclusions: Age estimation using CT can be significantly improved by combining information from the analysis of wisdom teeth with age estimation based on the clavicle.

Evaluation of distal femoral and proximal tibial epiphyseal plate in bone age estimation with 3.0T MRI: a comparison of current methods

OBJECTIVE

Dedouit et al, Kramer et al and Vieth et al defined different staging methods over different sequences in knee MRI for bone age determination. Our study aims to examine three different methods in which the maturation stages of the knee epiphyses are evaluated by MRI in the same population, to compare the methods and results and evaluate them for some age thresholds and to discuss their applicability in forensic age estimation.

METHODS

In this study, 597 knee images obtained using a 3.0T MR scanner were evaluated retrospectively. The T 1 weighted and proton density-weighted sequences were evaluated by two observers. Knee bone development was staged on the femur and tibia, and descriptive statistics were calculated for each stage according to age and sex. Descriptive statistics were presented according to the age and sex of the cases, and intra- and interobserver agreements were evaluated by the κ and κw statistics obtained by the Fleiss approach.

RESULTS

Significant changes were found in stages depending on age. The intra- and interobserver agreement levels were very good (κ > 0.80) for each method. The methods of Dedouit, Kramer and Vieth can be used as an additional criteria for forensic age estimation for 14, 15, 18 and 21 year thresholds.

CONCLUSION

Knee MRI stands out as an alternative modality for age estimation and it is necessary to prefer the method intended for the investigated age range with an individual-specific approach.

ADVANCES IN KNOWLEDGE

Our study stands out as the first study in which current classification methods were applied and compared in the same population for age estimation with knee MRI.

The influence of motion artefacts on magnetic resonance imaging of the clavicles for age estimation

PURPOSE

To determine how motion affects stage allocation to the clavicle's sternal end on MRI.

MATERIALS AND METHODS

Eighteen volunteers (9 females, 9 males) between 14 and 30 years old were prospectively scanned with 3-T MRI. One resting-state scan was followed by five intentional motion scans. Additionally, a control group of 72 resting-state scans were selected from previous research. Firstly, six observers allocated developmental stages to the clavicles independently. Secondly, they re-assessed the images, allocating developmental statuses (immature, mature). Finally, the resting-state scans of the 18 volunteers were assessed in consensus to decide on the "correct" stage/status. Results were compared between groups (control, prospective resting state, prospective motion), and between staging techniques (stages/statuses).

RESULTS

Inter-observer agreement was low (Krippendorff α 0.23-0.67). The proportion of correctly allocated stages (64%) was lower than correctly allocated statuses (83%). Overall, intentional motion resulted in fewer assessable images and less images of sufficient evidential value. The proportion of correctly allocated stages did not differ between resting-state (64%) and motion scans (65%), while correctly allocated statuses were more prevalent in resting-state scans (83% versus 77%). Remarkably, motion scans did not render a systematically higher or lower stage/status, compared to the consensus.

CONCLUSION

Intentional motion impedes clavicle MRI for age estimation. Still, in case of obvious disturbances, the forensic expert will consider the MRI unsuitable as evidence. Thus, the development of the clavicle as such and the staging technique seem to play a more important role in allocating a faulty stage for age estimation.

Cranial suture closure as an age indicator: A review

Cranial suture closure has been recognized for over a century as a useful trait for age estimation. Although this indicator has become a standard feature of age assessment protocols in skeletal remains, serious questions have been raised about its reliability. This article attempts to provide a comprehensive review of cranial suture closure as an age indicator from several perspectives, including its anatomy and history, as well as issues relating to validation, statistics, and the potential of technological advancements to improve outcomes. We further suggest a path forward for the use of cranial suture closure as an estimator of age. Although its unreliability has been widely reported, cranial suture closure still appears to have value as an aging method, and it is hoped that the information contained in this article can serve as a stepping stone toward more effective use of this indicator. The cranium is often more durable than other skeletal elements in both archaeological and forensic circumstances, so maximizing the effectiveness of cranial indicators is an important goal. It is hoped that recent advancements in technology and in analytical approaches to the cranial sutures could breathe some new life into this feature as an indicator of age.

Anatomic shape variants of extremitas sternalis claviculae as collected from sternoclavicular thin-slice CT-studies of 2820 male borderline-adults

Within medical age assessment practice, the indicator "medial clavicular ossification" constitutes crucial evidence capable of excluding age minority "beyond reasonable doubt" concerning age-disputed individuals doubtfully claiming children's rights during legal procedures. Yet, one of its characteristics affects the morphological variability including a fair amount of downright peculiar appearances. As a result, inexperienced examiners are tempted to classify actually not-assessable formations according to the two established developmental typologies of Schmeling et al. and Kellinghaus et al. being at the same time the most frequent systemic error of age-related clavicular taxation. Since a respective overview appears missing, the study extracts not-assessable shape variants of the medial collar bone from a large sample of 2820 male borderline-adults as seen from thin-slice, sternoclavicular computed tomography. The two already highlighted configurations "more than one, medial, secondary ossification centres" and "medial metaphyseal concavity" are found as the most commonly encountered features impeding reliable delineation of staging criteria. In accordance with previous literature, it is emphasized that "qualified" rating of extremitas sternalis claviculae within age assessment practice presupposes "knowledge about the diversity of [its] anatomic shape variants."

Union of the medial clavicular epiphysis in a South African Black skeletal sample

Current research points to an increase in the interest in and focus on the age at which the medial end of the clavicle begins and completes union in various populations worldwide. As it currently stands, no information exists for the South African population detailing the age at which this skeletal developmental marker commences or completes union. The aim of this study was to establish the age at which partial and complete unions occur and to find if there is any correlation between the age and the assigned stage score in a South African Black skeletal sample. Paired clavicles of 211 males and females (M = 101, F = 110) with ages ranging between 12 and 45 years from the Raymond A. Dart Collection of Human Skeletons were included. A strong correlation between age and the assigned stage score was observed for both males and females (rs = 0.73). No statistically significant differences between the stage of union at the left and right clavicles were observed (p = 0.9). In this sample, partial union was commonly observed in individuals in their third decade of life; while complete union occurred more often in individuals older than 30 years of age. Assessing and recording the degree of union at the medial end of the clavicle can be a helpful additional age-at-death indicator to use when establishing an age-at-death range. However, overlap and variability between the ages of individuals categorized as either displaying signs of partial or complete union were evident.

Secondary Ossification Center Appearance and Closure in the Pelvis and Proximal Femur

INTRODUCTION

Variable ossification patterns of the pelvis in skeletally immature patients can make the interpretation of pelvic radiographs challenging. Inconsistencies among prior studies and lack of sex comparisons underscore the need for a more comprehensive characterization of the secondary ossification centers. This study evaluates the chronology and sex differences for appearance and closure of pelvic and proximal femoral secondary ossification centers using computed tomography (CT).

METHODS

Patients who underwent abdominal and pelvic CT scans between January 2009 and December 2014 at 2 tertiary level 1 trauma centers were retrospectively reviewed. Patients between the ages of 2 and 32 years with adequate imaging of the pelvis and proximal femurs were included. Patients with a history of orthopaedic trauma or pathology affecting ossification were excluded. CT scans were assessed for the appearance and closure of the following secondary ossification centers: anterior inferior iliac spine (AIIS), anterior superior iliac spine (ASIS), femoral head (FH), greater trochanter (GT), iliac crest (IC), ischial tuberosity (IT), lesser trochanter (LT), posterior superior iliac spine (PSIS), symphysis pubis (SP), and triradiate cartilage (TRC). Basic descriptive statistics are reported.

RESULTS

A total of 496 CT scans met inclusion criteria (240 males and 256 females). The order of appearance of the secondary ossification centers was: (male) GT, LT, AIIS, IT, ASIS, PSIS, IC, and SP; (female) GT, LT, IT, AIIS, PSIS, IC, ASIS, and SP. The order of closure was similar: (male) TRC, LT, FH, AIIS, GT, ASIS, PSIS, IT, IC, and SP; (female) LT, TRC, AIIS, FH, GT, ASIS, PSIS, IT, IC, and SP. Female ossification centers appeared ∼1 to 2 years before males in all locations. Female ossification centers closed ∼1 to 2 years before males in all locations except TRC, IC, and SP.

CONCLUSIONS

The appearance and closure of the pelvis and proximal femur secondary ossification centers follow a predictable pattern of development, occurring slightly earlier in females than males. Knowledge of more precise ages of development and sex differences better characterize this complex skeletal development. Future studies may use secondary ossification centers to further evaluate skeletal maturity, assess pediatric pathology, and aid surgical management.

LEVEL OF EVIDENCE

Level III.

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.

The age of adolescence

Adolescence is the phase of life stretching between childhood and adulthood, and its definition has long posed a conundrum. Adolescence encompasses elements of biological growth and major social role transitions, both of which have changed in the past century. Earlier puberty has accelerated the onset of adolescence in nearly all populations, while understanding of continued growth has lifted its endpoint age well into the 20s. In parallel, delayed timing of role transitions, including completion of education, marriage, and parenthood, continue to shift popular perceptions of when adulthood begins. Arguably, the transition period from childhood to adulthood now occupies a greater portion of the life course than ever before at a time when unprecedented social forces, including marketing and digital media, are affecting health and wellbeing across these years. An expanded and more inclusive definition of adolescence is essential for developmentally appropriate framing of laws, social policies, and service systems. Rather than age 10-19 years, a definition of 10-24 years corresponds more closely to adolescent growth and popular understandings of this life phase and would facilitate extended investments across a broader range of settings.

The Demirjian versus the Willems method for dental age estimation in different populations: A meta-analysis of published studies

BACKGROUND

The accuracy of radiographic methods for dental age estimation is important for biological growth research and forensic applications. Accuracy of the two most commonly used systems (Demirjian and Willems) has been evaluated with conflicting results. This study investigates the accuracies of these methods for dental age estimation in different populations.

METHODS

A search of PubMed, Scopus, Ovid, Database of Open Access Journals and Google Scholar was undertaken. Eligible studies published before December 28, 2016 were reviewed and analyzed. Meta-analysis was performed on 28 published articles using the Demirjian and/or Willems methods to estimate chronological age in 14,109 children (6,581 males, 7,528 females) age 3-18 years in studies using Demirjian's method and 10,832 children (5,176 males, 5,656 females) age 4-18 years in studies using Willems' method. The weighted mean difference at 95% confidence interval was used to assess accuracies of the two methods in predicting the chronological age.

RESULTS

The Demirjian method significantly overestimated chronological age (p<0.05) in males age 3-15 and females age 4-16 when studies were pooled by age cohorts and sex. The majority of studies using Willems' method did not report significant overestimation of ages in either sex. Overall, Demirjian's method significantly overestimated chronological age compared to the Willems method (p<0.05). The weighted mean difference for the Demirjian method was 0.62 for males and 0.72 for females, while that of the Willems method was 0.26 for males and 0.29 for females.

CONCLUSION

The Willems method provides more accurate estimation of chronological age in different populations, while Demirjian's method has a broad application in terms of determining maturity scores. However, accuracy of Demirjian age estimations is confounded by population variation when converting maturity scores to dental ages. For highest accuracy of age estimation, population-specific standards, rather than a universal standard or methods developed on other populations, need to be employed.

Intraindividual incongruences of medially ossifying clavicles in borderline adults as seen from thin-slice CT studies of 2595 male persons

In the past, numerous studies have documented the possibility of intraindividual differing appearances of the paired age-marker "medial clavicular ossification" in borderline adults. However, the extent of the divergences is rarely mentioned. Against that the article describes this phenomenon from a large sample of 2595 male persons by means of thin-slice CT imaging of the sternoclavicular regions. For determining the ossification stage of the medial clavicles, the two accepted classifications by Schmeling et al. (five main stages) and Kellinghaus et al. (six substages) were applied and buildings deviating from that labelled as atypical "norm variants". The longstanding observation could be confirmed that intraindividual stage discrepancies of this age indicator are generally moderate and do not exceed one main stage or two substages of the respective classifications. It is concluded that stage determination should be scrutinized, if a dissimilarity seems to show larger differences.

Comparison of imaging planes during CT-based evaluation of clavicular ossification: a multi-center study

Determining the ossification stage of the medial clavicular epiphysis by computed tomography represents the currently recommended methodology for the question of whether a living individual has completed the 18th or 21st year of life. In the present study, thin-slice CT scans of 1078 sternoclavicular joints were reconstructed in axial and coronal image series and evaluated according to the two classification systems established for age diagnostics using the clavicle. Both image series (axial and coronal) were analyzed separately. When comparing the results of axial and coronal view, a different ossification stage was found in 35.6% of the clavicles. The results suggest an influence of the imaging plane on the process of stage determination. In order to further approximate the three-dimensional and asymmetrical structure of the epiphyseal ossification center, the usage of at least two different reformation types may be recommended. In practice, only those reference studies should be applied which exactly employed the same number and orientations of the reformation types that are going to be used in the respective routine case.

CT evaluation of medial clavicular epiphysis as a method of bone age determination in adolescents and young adults

PURPOSE

We aimed to investigate the use of computed tomography (CT) staging of the medial clavicular epiphysis ossification in forensic bone age determination, and find a CT criterion to determine whether an individual is adult or not.

METHODS

Chest CT and pulmonary CT angiography exams of 354 patients between 10 and 30 years of age (mean, 21.4 years) were retrospectively evaluated for epiphyseal ossification phase of the bilateral medial clavicles (708 clavicles) and compared with the sex and chronologic age of the individuals. The ossification phase of the medial clavicular epiphyses was classified from stage I to stage V using a modified staging system.

RESULTS

Epiphyseal ossification center appeared from 11 to 21 years of age. Partial fusion occurred between 16 and 23 years of age. Complete fusion was first achieved at the ages of 18 and 19 years for male and female individuals, respectively. The probability of an individual being ≥18 years old was 70.8% in stage III A and 100% in stages III B, IV, and V in females and males.

CONCLUSION

CT evaluation of the medial clavicular epiphysis is helpful in forensic age determination and stage III B can be used as a criterion to make the prediction that an individual is older than 18 years.

The role of forensic medicine and forensic dentistry in estimating the chronological age of living individuals in Hamburg, Germany

Age estimation represents one of the primary responsibilities of forensic medicine and forensic dentistry. It is an integral procedure aiming to estimate the chronological age of an individual, whose age is either unknown or doubtful, by means of assessing the stage of dental, skeletal, and physical development. The present publication reviews the methods and procedures used in estimating the age of young living individuals as well as the experiences of the Institute of Legal Medicine in Hamburg-Eppendorf, Germany, during the last 25 years. From 1990 to 2015, 4223 age estimations were carried out in Hamburg. During this time, forensic age estimation was requested by different concerned authorities including courts, the foreigners' registration office (Zentrale Ausländerbehörde), and the state office of education and consultation (Landesbetrieb Erziehung und Beratung). In the context of judicial proceedings, orthopantomograms, as well as X-ray examinations of both the left hand and the medial clavicular epiphyses were carried out in accordance with AGFAD recommendations. For investigations not associated with judicial proceedings, orthopantomogram examinations play a key role in the process of age estimation, due to their high diagnostic value and low radiation exposure. Since 2009, mainly unaccompanied young refugees were examined for age estimation. Orthopantomograms and clinical-physical examinations have been used as essential steps in this context to determine whether an individual is 18 years or less. Additional X-ray examinations of the left hand and the medial clavicular epiphyses have been used less frequently.

Evaluation of the ossification of the medial clavicle according to the Kellinghaus substage system in identifying the 18-year-old age limit in the estimation of forensic age-is it necessary?

The evaluation of the ossification of the medial clavicular epiphysis being part of an assigned expert approach according to standard plays an important role within civil and criminal proceedings in assessing whether a person has reached her/his 19th or 22nd year of age. Evaluation of the medial clavicular epiphysis with thin-section CT is one of the methods recommended by the Study Group on Forensic Age Diagnostics of the German Association of Forensic Medicine. In this retrospective study, we evaluated the thin-section CT (section thickness of 0.6 and 1 mm) images of 254 patients (146 male, 108 female) with an age range of 13-28 years according to the Kellinghaus substage system. The mean values of female patients were observed to be about 10 months lower for stage 2a than the mean values of the male patients, about 13 months lower for stage 2b, and about 18 months lower for stage 2c. The earliest appearance for stage 3c was at 19 years in both sexes. Our data from this study were consistent with both our previous studies and the data of other studies. We think that stage 3c is important in determining whether a person has reached the age of 18 or not and, therefore, that the Kellinghaus substage system is a requirement in the assessment of forensic age.

Bone age estimation based on multislice computed tomography study of the scapula

Progress in medical imaging has opened new areas of research in forensic anthropology, especially in the context of the study of bone age assessment. The study of bone age has become a useful tool for age estimation at death or age of young adult migrants in an anthropological context. We retrospectively evaluated multislice computed tomography (MSCT) explorations focused on scapulae of 232 individuals (123 males; 109 females) aged between 8 and 30 years old. Computed tomography (CT) scans were viewed in axial and multiplanar reconstructed images using OsiriX 5.9 (64 bit)®. The ossification centers of the scapula studied were as follows: acromial, sub-coracoid, glenoid, coracoid, coracoid apex, and inferior angle epiphyses. Fusion status was scored based on a five-stage system (stage 1: no ossification, stage 2: visualization of an ossification center, stage 3: partial ossification, stage 4: full ossification associated to an epiphyseal scar, and stage 5: full ossification without epiphyseal scar). Intra-observer variability was excellent, and inter-observer variability was good, demonstrating the reliability of this MSCT staging system. The fusion of scapular ossification centers was statistically associated with age (p < 0.001) but not with sex (p > 0.05). In conclusion, MSCT of the scapula is an efficient method for age assessment, which is complementary to preexisting methods particularly for specifying the 18-year threshold. Further studies with larger groups are needed to support our results.

Forensic age estimation of living persons from the knee: Comparison of MRI with radiographs

To perform a study to clarify how strong the chronological age relates to ossification of the knee in Chinese on X-rays and the MRI when a similar four-stage grading system was used. 322 individuals with conventional radiographs and MRI were collected from routine medical investigations and evaluated retrospectively. Bland Altman plots were performed to reveal the agreement of grading of MRI and radiograph. Regression analysis was conducted to establish a mathematical model for age estimation. The ossification process of the knee occurs earlier in females than in males for about 1-2 years. The process on X-ray grading is consistently higher than that of MRI. The chronological age is well correlated with both grading of MRI and radiograph (all p values were less than 0.001). By comparison, the R-square of grading of MRI were relatively higher than that of radiograph. Finally, the chronological age is well correlated with the ossification of the knee when both grading of MRI and radiograph were used, with the R-square for MRI were relatively higher than that of radiograph. Furthermore, the use of MRI will reduce exposure to X-ray radiation as much as possible.

Ossification of the Medial Clavicular Epiphysis on Chest Radiographs: Utility and Diagnostic Accuracy in Identifying Korean Adolescents and Young Adults under the Age of Majority

The aim of our study was to evaluate the utility and diagnostic accuracy of the ossification grade of medial clavicular epiphysis on chest radiographs for identifying Korean adolescents and young adults under the age of majority. Overall, 1,151 patients (age, 16-30) without any systemic disease and who underwent chest radiography were included for ossification grading. Two radiologists independently classified the ossification of the medial clavicular epiphysis from chest radiographs into five grades. The age distribution and inter-observer agreement on the ossification grade were assessed. The diagnostic accuracy of the averaged ossification grades for determining whether the patient is under the age of majority was analyzed by using receiver operating characteristic (ROC) curves. Two separate inexperienced radiologists assessed the ossification grade in a subgroup of the patients after reviewing the detailed descriptions and image atlases developed for ossification grading. The median value of the ossification grades increased with increasing age (from 16 to 30 years), and the trend was best fitted by a quadratic function (R-square, 0.978). The inter-observer agreements on the ossification grade were 0.420 (right) and 0.404 (left). The area under the ROC curve (AUC) was 0.922 (95% CI, 0.902-0.942). The averaged ossification scores of 2.62 and 4.37 provided 95% specificity for a person < 19 years of age and a person ≥ 19 years of age, respectively. A preliminary assessment by inexperienced radiologists resulted in an AUC of 0.860 (95% CI, 0.740-0.981). The age of majority in Korean adolescents and young adults can be estimated using chest radiographs.

The completely fused medial clavicular epiphysis in high-frequency ultrasound scans as a diagnostic criterion for forensic age estimations in the living

The assessment of ossification of the medial clavicular epiphysis plays a decisive role in the forensic age estimation of living subjects. Primarily for reasons of minimizing the radiation exposure currently associated with such evaluations, non-ionizing methods would be an advance.This study pursued the question whether full union of the medial clavicular epiphysis, visualized by high-frequency sonography, is a reliable criterion for age-threshold determinations. The ossification stage of the medial clavicular epiphysis of 215 female and 195 male volunteers, aged between 14 and 26 years, was evaluated in bilateral sonograms. Stage 4, defined as complete fusion by Schulz et al. (Int J Legal Med 122:163-167, 2008), was observed on at least one body side in 48 of 334 individuals younger than 21 years (14.4 %) and in 32 of 264 individuals younger than 18 years (12.1 %).With the high-frequency ultrasound used in this study, even the smallest convexities of the medial clavicular ending can be visualized. This may have led to overestimation of the ossification stage. It is not clear whether any observed roundings in the sonograms should actually be interpreted in terms of stages 3 and 4 as defined by Schulz. Also, due to the low penetration depth of high-frequency ultrasound waves, epiphyseal plate residues and ossification centers may have remained undetected. Reliable differentiation of the stages 1-4 with high-frequency sonography is thus difficult, and the results suggest that this method is not a radiation-free alternative to computed tomography, the current gold standard for determining age thresholds.

Virtual anthropology: useful radiological tools for age assessment in clinical forensic medicine and thanatology

Virtual anthropology consists of the introduction of modern slice imaging to biological and forensic anthropology. Thanks to this non-invasive scientific revolution, some classifications and staging systems, first based on dry bone analysis, can be applied to cadavers with no need for specific preparation, as well as to living persons. Estimation of bone and dental age is one of the possibilities offered by radiology. Biological age can be estimated in clinical forensic medicine as well as in living persons. Virtual anthropology may also help the forensic pathologist to estimate a deceased person's age at death, which together with sex, geographical origin and stature, is one of the important features determining a biological profile used in reconstructive identification. For this forensic purpose, the radiological tools used are multislice computed tomography and, more recently, X-ray free imaging techniques such as magnetic resonance imaging and ultrasound investigations. We present and discuss the value of these investigations for age estimation in anthropology.

Forensic age estimation by the Schmeling method: computed tomography analysis of the medial clavicular epiphysis

The variability of anthropometric measures, such as the degree of ossification, among societies should be taken into account when estimating age. The degree of ossification of the medial clavicle can be determined with thin-section computed tomography (CT), which is one of the methods recommended by the Study Group on Forensic Age Diagnostics of the German Association of Forensic Medicine. The purpose of this retrospective study was to investigate the applicability of thin-section CT analysis of the degree of ossification of the medial clavicle in a Turkish population. We evaluated the CT images (1-mm slice thickness) of 503 patients (362 male, 141 female; age, 10-35 years) using the Schmeling five-stage method. The Spearman's correlation analysis revealed a positive correlation between age and ossification stage in both male and female patients (total group: rho = 0.838, p < 0.001; male: rho = 0.831, p < 0.001; female: rho = 0.856, p < 0.001). The linear regression analysis results indicated that the ossification stage of the medial clavicle is a good predictor when estimating age (r (2) = 0.735 for all patients, 0.734 for male patients, 0.741 for female patients). Sex differences in ossification stages were observed only for stage 1 and 4 ossification. We believe that future research could expand the database on this topic and contribute to improvements in this measurement method.

CT evaluation of timing for ossification of the medial clavicular epiphysis in a contemporary Western Australian population

The clavicle is the first bone to ossify in the developing embryo and the last to complete epiphyseal union. It is the latter sustained period of growth that has attracted the interest of skeletal biologists and forensic practitioners alike, who collectively recognize the important opportunity this bone affords to estimate skeletal age across the prenatal to early adult lifespan. Current research is largely directed towards evaluating the applicability of assessing fusion in the medial epiphysis, specifically for determining age of majority in the living. This study aims to contribute further insights, and inform medicolegal practice, by evaluating the Schmeling five-stage system for the assessment of clavicular development in a Western Australian population. We retrospectively evaluated high-resolution multiple detector computed tomography (MDCT) scans of 388 individuals (210 male; 178 female) between 10 and 35 years of age. Scans are viewed in axial and multiplanar reconstructed (MPR) images using OsiriX®. Fusion status is scored according to a five-stage system. Transition analysis is used to calculate age ranges and determine the mean age for transition between an unfused, fusing and fused status. The maximum likelihood estimates (in years) for transition from unfused to fusing is 20.60 (male) and 19.19 (female); transition from fusing to complete fusion is 21.92 (male) and 21.47 (female). Results of the present study confirm the reliability of the assessed method and demonstrate remarkable consistency to data reported for other global populations.

Virtual anthropology and forensic identification using multidetector CT

Virtual anthropology is made possible by modern cross-sectional imaging. Multislice CT (MSCT) can be used for comparative bone and dental identification, reconstructive identification and lesion identification. Comparative identification, the comparison of ante- and post-mortem imaging data, can be performed on both teeth and bones. Reconstructive identification, a considerable challenge for the radiologist, identifies the deceased by determining sex, geographical origin, stature and age at death. Lesion identification combines virtual autopsy and virtual anthropology. MSCT can be useful in palaeopathology, seeking arthropathy, infection, oral pathology, trauma, tumours, haematological disorders, stress indicators or occupational stress in bones and teeth. We examine some of the possibilities offered by this new radiological subspeciality that adds a new dimension to the work of the forensic radiologist. A multidisciplinary approach is crucial and involves communication and data exchange between radiologists, forensic pathologists, anthropologists and radiographers.

Correlation between age and the parameters of medial epiphysis and metaphysis of the clavicle using CT volume rendering images

OBJECTIVES

The aim of this study was to evaluate the correlation between age and the parameters of medial epiphysis of clavicle based on CT volume rendering (VR) images.

MATERIALS AND METHODS

The CT images of the medial clavicle from 795 teenagers (387 male and 408 female) between 15 and 25 years were collected in East and South China. VR images were recombined from 0.60 mm thickness slice CT images. The ratio of epiphyseal diameter/metaphyseal diameter and the ratio of epiphyseal area/metaphyseal area of two sides of medial clavicle were measured and calculated by three different examiners, the quantitative data consistency was checked by intraclass correlation coefficients (ICC). The diameter ratio of left and right side are depicted as X1 and X3, and the area ratio of left and right side as X2 and X4. Descriptive statistic analysis of the data was performed and several mathematical models were established using least square. CT images from additional 60 teenagers (30 male and 30 female) were used to verify the accuracy of the established mathematical models.

RESULTS

ICC indicated that the measurement of epiphyseal diameter, metaphyseal diameter, the ratio of epiphyseal diameter/metaphyseal diameter, epiphyseal area, metaphyseal area and the ratio of epiphyseal area/metaphyseal area of medial clavicle in the left and right side of the three examiners was approaching 1. The 95% reference range for the mean of every examination of both genders gradually increased with age. Females' data indicated by medial epiphysis of the clavicle development were earlier than male's, especially from 15 to 21 years. The difference of medial epiphysis of the clavicle development in gender becomes smaller after 21 years. The highest accuracy of the mathematical models made clear that male's accuracy was 73.5% (±1.0 year) and 85.3% (±1.5 year), and female's was 68.6% (±1.0 year) and 82.2% (±1.5 year) respectively.

CONCLUSION

The methods of data collection and analysis were reliable and feasible. Combined the high accuracy of these established mathematical models, it is applicable to use the ratio of epiphyseal diameter/metaphyseal diameter and the ratio of epiphyseal area/metaphyseal area of left and right side of medial clavicle to estimate the teenager's age. Bearing this in mind, further studies are needed to evaluate slice thickness as the most critical parameter.

Forensic age estimation from the clavicle using 1.0T MRI--preliminary results

OBJECTIVES

As forensic age estimations in the living are performed without medical indication, there is a need for the development of non-ionizing methods. This study investigates the use of 1.0T MRI to visualize the ossification status of the medial end of the clavicle.

MATERIAL AND METHODS

T2 weighted 3D images were collected from a 1.0T MR system. We prospectively scanned 102 subjects, 47 autopsy cases and 55 living volunteers (12-33 years). Images were scored in blind trials by three observers using a 4-stage system. Observers differed by level of training and radiological expertise.

RESULTS

Motion artefacts reduced image resolution in living subjects. However, mean age at stage 4 was significantly different from mean age at stage 2 and 3. The minimum age at stage 4 was 19.8 years. Inter-observer agreement was moderate for autopsy cases and slight for living subjects. By contrasting subjects of "incomplete fusion" (≤ stage 3 on both sides) against "fused" (at least one stage 4), agreement rate rose to moderate (K=0.414) for living subjects. Despite the low agreement rate, no subject younger than 18 years was assessed as having "fused" clavicles.

CONCLUSION

At lower image resolution, a 2-stage system increases agreements rates among observers. To further increase accuracy, clavicle staging needs to be performed by trained observers. If available, a 1.0T MR system may be used for age estimation in the living. However, further studies are needed to ensure that the ability to discriminate adults from minors, i.e. 18 years, is maintained.