OBJECTIVES: To examine the reliability and accuracy of Walker's model for estimating the sex of Han adults in western China by using cranium three-dimensional (3D) CT reconstruction, and to study the suitable cranial sex estimation model for Han people in western China. METHODS: A total of 576 cranial CT 3D reconstructed images from Hanzhong Hospital in Shaanxi Province from 2017 to 2021 were collected. These images were divided into the experimental group with 486 samples and the validation group with 90 samples. Walker's model was used by observer 1 to estimate the sex of experimental group samples. The logistic function applicable to Han people in western China was corrected by observer 1. The 90 samples in the validation group were scored and substituted into the modified logistic function to complete the back substitution test by observer 1, 2 and 3. RESULTS: The accuracy of sex estimation of Han adults in western China was 63.2%-77.2% by applying Walker's model. The accuracy of modified logistic function was 82.9%. The accuracy of sex estimation through back substitution test by 3 observers was 75.6%-91.1%, with a Kappa value of 0.689 (P<0.05) for inter-observer consistency and 0.874 (P<0.05) for intra-observer consistency. CONCLUSIONS There are great differences in bone characteristics among people from different regions. The modified logistic function can achieve higher accuracy in Han adults in western China.
Humans ; Adult ; Reproducibility of Results ; Sex Determination by Skeleton/methods* ; Forensic Anthropology ; Skull/anatomy & histology* ; Imaging, Three-Dimensional ; China ; Tomography, X-Ray Computed

Objective To estimate sex based on patella measurements of Sichuan Han population by computed tomography three-dimensional volume reconstruction technique, and to explore the application value of patella in sex estimation. Methods CT three-dimensional volume reconstruction images of patella of 250 individuals were collected, the four measurement indicators including patellar length, patellar width, patellar thickness, and patellar volume were measured. The t-test was used to determine measurement indicators with sex differences. Fisher discriminant analysis was used to establish the sex discriminant function and the prediction accuracy was calculated by leave-one-out cross validation. Results The sex differences of the four measurement indicators had a statistical significance （P<0.05）. The accuracy rate of the univariate discriminant function established by the patellar length was the highest （82.0%）. The accuracy rates of the all indicators discriminant function and the stepwise discriminant function were 80.4% and 81.6%, respectively. Conclusion It is feasible and accurate to estimate sex of Sichuan Han population by patella measurements with CT three-dimensional volume reconstruction technique. The method may be used as an alternative for sex estimation of Sichuan Han population when other bones with higher accuracy are not available.
Discriminant Analysis ; Female ; Forensic Anthropology ; Humans ; Imaging, Three-Dimensional ; Male ; Patella/diagnostic imaging* ; Sex Determination by Skeleton ; Tomography, X-Ray Computed

Objective Logistic regression method was used to establish a multiple regression sex discriminant function to discriminate the complete skull model and the incomplete skull model without frontal bone, occipital bone and mandible of Uygur adults in Turpan, Xinjiang. Methods A total of 117 （60 male and 57 female） three-dimensional skull models were collected by CT. Sixteen cranial measurement indexes were measured and calculated by computer software. The multivariate regression sex discriminant function was established with Logistic regression method and retrospectively tested. Results Among the 16 measurement indexes, except for nose width （x₇） and maximum frontal breadth （x₁₃）, the remaining 14 indexes had statistical significance of differences between male and female （P<0.05）. For the discriminant function of complete skull established by eyebrow arch convexity （x₄）, mastoid width （x₆）, maximum cranial length （x₁₂）, cranial base length （x₁₅）, cranial circumference （x₁₆）, the male and female discrimination accuracy was 90.0% and 94.7%, respectively. For the sex discriminant function of incomplete skull without frontal bone established by mandibular angle width （x₁₀）, mandibular height （x₁₁） and cranial circumference （x₁₆）, the discrimination accuracy of male and female was 85.0% and 84.2%, respectively. For the sex discriminant function of incomplete skull without occipital bone established by the index of eyebrow arch convexity （x₄）, the discrimination accuracy of male and female was 80.0% and 73.7%, respectively. For the sex discriminant function of incomplete skull without mandible established by frontal chord （x₅） and occipital protrusion angle （x₉）, the discrimination accuracy of male and female was 85.0% and 78.9%, respectively. Conclusion The computer software and system developed in our study can achieve sex discrimination of complete skulls and incomplete skulls without frontal bone, occipital bone or mandible.
Adult ; China ; Discriminant Analysis ; Ethnicity ; Female ; Forensic Anthropology ; Humans ; Imaging, Three-Dimensional ; Jaw/diagnostic imaging* ; Male ; Retrospective Studies ; Sex Characteristics ; Sex Determination by Skeleton/methods* ; Skull/diagnostic imaging* ; Tomography, X-Ray Computed/methods*

Sex estimation is one of the crucial procedures in the biological profile identification of human skeletal remains. Knowing sex of unknown case can lead to accurate and appropriate methods for predicting age, stature, ancestry, or even personal identification. Skull is one of the most reliable one among other skeletons and it is usually retained for both archaeological and forensic contexts. Although many morphological features and metric measurements of skull have been studied for sexing, but to the best of our knowledge is no study on maxillary suture length for sex estimation. Therefore, this study aims to develop a new sex estimation method for a Thai population by determining three maxillary suture lengths: anterior, transverse, and posterior maxillary suture, by computerizing amount of pixel obtained from photographs of these sutures. The present study was conducted on 190 Thai bone samples of which 96 were males and 94 were females. Independent t test revealed statistically significant difference (P < 0.01) between males and females in all maxillary suture measurements. Equations derived from prediction model, which required three maxillary suture lengths gave 76.8421% accuracy from the leave-one-out cross validation in estimating sex percentage accuracies in predicting sex from these equations, which were relatively moderate. This study provides a novel and objective sex estimation method for Thais. It suggests that maxillary suture length can be applied for sex estimation. The new computerized technique will contribute basis knowledge and method for sex estimation, especially when only base of skull is available in forensic circumstance.
Asian Continental Ancestry Group* ; Cranial Sutures ; Female ; Humans ; Male ; Methods* ; Sex Determination Analysis ; Skeleton ; Skull ; Skull Base ; Sutures* ; Thailand

Individual identification by measuring the human skeleton is an important research in the field of forensic anthropology. Computed tomography （CT） technology can provide high-resolution image of skeleton. Skeleton image can be reformed by software in the post-processing workstation. Different skeleton measurement indexes of anthropology, such as diameter, angle, area and volume, can be measured on section and reformative images. Measurement process is barely affected by human factors. This paper reviews the literatures at home and abroad about the application of measuring skeleton by CT in forensic anthropology research for individual identification in four aspects, including sex determination, height infer, facial soft tissue thickness measurement and age estimation. The major technology and the application of CT in forensic anthropology research are compared and discussed, respectively.
Age Determination by Skeleton ; Bone and Bones/diagnostic imaging* ; Forensic Anthropology/trends* ; Humans ; Sex Determination Analysis ; Software ; Tomography, X-Ray Computed/methods*

INTRODUCTIONTo the best of our knowledge, the sexually dimorphic characteristics of the craniofacial region among the South Indian population are not available in the current literature. We aimed to determine these characteristics using discriminant function analysis.

METHODSA total of 80 recent skulls (40 male, 40 female) from the Department of Anatomy, Yenepoya Medical College, Yenepoya University, Karnataka, India, were analysed. Ten craniofacial parameters were measured and subjected to univariate and multivariate statistical analyses using the Statistical Package for the Social Sciences version 13.0.

RESULTSStatistical analyses revealed that the differences in the bizygomatic, orbital and biorbital breadths of males and females were significant (p < 0.05). Direct method gave an accuracy of 68.8% for sex determination. In stepwise analysis, bizygomatic breadth and upper facial height were selected, giving a 65.0% accuracy for sex prediction.

CONCLUSIONCraniofacial parameters are sexually dimorphic. The present study established several features of craniofacial morphometry that can be used for sex determination among the South Indian population. The findings of the present study serve as a foundation for future studies that aim to compare craniofacial parameters among various ethnic groups in South India.

Adult ; Female ; Humans ; India ; Male ; Middle Aged ; Sex Characteristics ; Sex Determination by Skeleton ; methods ; Skull ; anatomy & histology

OBJECTIVE: To establish a CT staging method of sternal end of clavicle epiphyseal growth for teenagers by thin layer CT scan, multiplanar reconstruction (MPR) and volume reconstruction (VR) technologies. METHODS: The CT imaging characteristics, which collected from 460 teenagers (aged from 15 to 25) in East and South China, were studied through both sternal ends of clavicles' imagings by thin layer coronal CT scan and axial CT scan, MPR and VR technologies. The parameters of sternal end of clavicle including the longest diameter of epiphysis, the longest diameter of metaphysis, their length ratio, area of epiphysis, area of metaphysis, and their area ratio were measured and calculated in order to establish new classification. RESULTS: Based on the staging method of Schmeling, integrating the CT imaging reconstruction information of sternal end of clavicle, the new classification of sternal end of clavicle epiphyseal growth were divided into 1 to 5 stages, and stage 2 and stage 3, respectively, contained a, b and c sub-classification. CONCLUSION This new classification has merits of large sample size, wide age range and easy operability. By using CT imaging reconstruction techniques and analyzing the data which closely related to sternal end of clavicle epiphyseal growth of teenagers, the feasibility of the staging method could be increased.
Adolescent ; Adult ; Age Determination by Skeleton/methods* ; China ; Clavicle/growth & development* ; Epiphyses/growth & development* ; Feasibility Studies ; Female ; Forensic Anthropology ; Humans ; Image Processing, Computer-Assisted ; Male ; Osteogenesis ; Sex Characteristics ; Sternum/growth & development* ; Tomography, X-Ray Computed ; Young Adult

OBJECTIVE: To discuss bone development trend in the knee joint of Tibetan teenagers in Sichuan province and to effectively update the database for estimating the living age of Tibetan teenagers in terms of bone age of the knee joint. METHODS: Radiographs including epiphysis of distal femur, proximal tibia and proximal fibula were taken from 483 Tibetan male and female teenagers aged from 14 to 19 years old in Aba prefecture of Sichuan province in order to observe epiphyseal growth situation. The descriptive data of the epiphyseal closure ages of these teenagers' knee joints were statistically analyzed by SPSS 16.0 software. RESULTS: The distal femur epiphyseal closure occurred earliest, while the proximal fibula epiphyseal closure occurred latest. The epiphyseal growth of knee joints of females occurred about one year earlier than that of males. CONCLUSION The forensic information and data related to Tibetan teenagers' bone age identification should be updated regularly. These results provide potential value for the practice of forensic medicine, anthropology and clinical medicine.
Adolescent ; Age Determination by Skeleton/methods* ; Bone Development/physiology* ; China/ethnology* ; Epiphyses/growth & development* ; Female ; Femur/growth & development* ; Humans ; Knee Joint/growth & development* ; Male ; Sex Characteristics ; Tibia/growth & development* ; X-Ray Film ; Young Adult

OBJECTIVE: To explore the correlation between volume rendering (VR) statistics of medial clavicular epiphysis and living age, and establish the mathematical models for living age evaluation using the CT image of medial clavicular epiphysis based on the growth rules of osteoepiphysis of medial clavicle. METHODS: The CT images of the medial clavicles from 795 teenagers aged 15-25, 387 males and 408 females, were collected in East and South China. VR 3D images were reconstructed from 0.60 mm-thick slice CT images. The epiphyseal diameter, sternal end diameter, and their respective diameter ratio (the left: X1; the right: x3); epiphyseal area, sternal end area, and their respective area ratio (the left: x2; the right: x4), were measured and calculated. All these observations were analyzed using SPSS 19.0 statistical software. The statistical differences in gender and age were analyzed by Mann-Whitney U test. The mathematical models were established using least square. Sixty trained subjects, 30 males and 30 females, were tested to verify the accuracy of the established mathematical models. RESULTS: In the group of same age, x1 showed significant difference in gender; the same results were observed in x2, x3, and x4, which suggested that the growth rules of osteoepiphysis of medial clavicle were highly correlated with living age. The accuracy of these mathematical models were all above 67.6% (+/- 1.0 year) and 78.5% (+/- 1.5 year). CONCLUSION The mathematical models with reasonable accuracy could be manageable in practice to confirm the conclusion of the atlas method. The current study can contribute to the single skeletal age evaluation.
Adolescent ; Adult ; Age Determination by Skeleton/methods* ; Algorithms ; China ; Clavicle/growth & development* ; Epiphyses/growth & development* ; Female ; Humans ; Imaging, Three-Dimensional/statistics & numerical data* ; Male ; Models, Theoretical ; Osteogenesis ; Sex Characteristics ; Tomography, X-Ray Computed ; Young Adult

OBJECTIVE: To further improve the accuracy of bone age identification using the time of secondary ossification center appearance and epiphyseal fusion of 7 joints to estimate the age of living individuals. METHODS: DR films were taken from 7 parts including sternal end of clavical and the left side of shoulder, elbow, carpal, hip, knee and ankle joints of 1 709 individuals who came from eastern China, central China and southern China, whose ages were between 11.0 and 20.0 years. From those 7 joints 24 osteal loci were selected as bone age indexes, which could better reflect age growth of teenagers. The characteristics of secondary ossification center appearance and epiphyseal fusion were observed, and the mean and age range of secondary ossification center appearance and epiphyseal fusion were calculated. RESULTS: The fusion time of the 24 epiphyses were advanced at different degrees, the most obvious epiphyses the sternal end of clavicle, scapular acromial end, distal end of the radius, distal end of the ulna, iliac crest, ischial tuberosity, the upper and lower end of tibia and fibula. The appearance time of sternal end of clavicle, scapular acromial end, iliac crest and ischial tuberosity epiphyses were all found to be after the age of 12, and the female's age, approximately 1 year ahead of schedule in comparison with the male's. CONCLUSION The relevant forensic information and data for bone age identification should be updated every 10-15 years so as to provide accurate and objective evidence for court testimony, conviction and sentencing.
Adolescent ; Age Determination by Skeleton/methods* ; Asian People/ethnology* ; Bone Development/physiology* ; Bone and Bones/diagnostic imaging* ; Child ; China/ethnology* ; Clavicle/growth & development* ; Epiphyses/growth & development* ; Female ; Forensic Anthropology/methods* ; Humans ; Joints/growth & development* ; Male ; Sex Characteristics ; Tomography, X-Ray Computed ; Young Adult