Discriminant function analysis for sex determination using landmark coordinate data from three-dimensional mandible models

In this study, we aimed to investigate the sex-discriminating potential of mandible dimensions, which we hypothesise can be measured easily and can indicate various sex discriminant functions in a simple manner. Statistical analysis was performed using data from five linear measurements and 10 indexes acquired from 14 landmark coordinates on 240 three-dimensional Korean mandible models (120 male and 120 female). The Korean mandible showed sex dimorphism in all the measurements and in four indexes (p < 0.01). Discriminant functions were generated by univariate, bivariate, and multivariate analyses using direct and stepwise methods, with accuracy ranging from 51.3% to 89.6%. Moreover, when comparing the dimensions of Korean mandibles with other populations, morphological differences were observed, thus implying that the sex discriminant functions can be generated according to each population. Therefore, in the present study, we noted that the various discriminant functions assessed using three-dimensional models of the mandible in this study indicated that the mandible dimensions alone had sex-discriminant potential, and our findings thus provided useful information for forensic examiners to accurately predict sex in a Korean population.     

Sex determination from talus in Chinese population by three-dimensional measurement approach

ObjectiveThe determination of sex is an essential part of building the biological profile for unknown human remains. Sex determination from talus in Chinese population has been rarely reported. The aim of this study was to determine sex by discriminant function analysis through talus measurement in Chinese population.Methods48 male and 47 female Chinese northeast subjects were taken in this research. The ankle joints of these subjects were scanned by CT. In total, thirteen indexes were measured through Mimics and Magics software. Length and breadth indexes of total talus, trochlea, talar head, medial and lateral malleolus articular surface were mainly selected. Nine of them were measured through Mimics software. The other four indexes were measured through Magics software. All data were analyzed by independent-samples t-test in SPSS and Stata software. Discriminant function equations were generated for sex determination.ResultsAll the indexes were normally distributed. No significant difference between left and right talus in either males or females was identified (P > 0.05). All results showed significant sexual difference (P < 0.05) except posterior breadth of trochlea. The average accuracy of sex determination ranged from 95.85% to 98.45% in the direct method and 98.95% in the stepwise method.ConclusionsLength indexes showed higher accuracy rate than breadth ones. Length of lateral malleolus articular surface was the best discriminator of sexual dimorphism. Talus was proved effective for sex determination in Chinese population. This study provided a remarkable reference for sex determination in forensic science.     

A new landmark for measuring the Ischium-Pubis index for sex determination by using three-dimensional models of South Korean population

The Ischium-pubis index (IPI) is one of the parameters of sex determination using the hip bone. IPI is defined as the percentage of the pubis length to the ischium length. On dry bones, the combined starting point of the lengths of the pubis and ischium is in the acetabulum. In this study, we evaluated the accuracy of IPI determination by using three-dimensional computational models. We compared the accuracy of three acetabular landmarks: the traditional acetabulum notch, the deepest point of the acetabulum and the point on the superior acetabulum border. The deepest point of the acetabulum was newly defined to facilitate the computational measurement. One-hundred models reconstructed from computed tomography scans of Korean adult cadavers were measured for the pubic and ischium length. After computer-assisted landmark indication procedure on software that enables three-dimensional model handling, measurements were automatically calculated. In the Korean adult population, measurements involving the deepest point of the acetabulum have shown the highest accuracy, 91%. We compared our results with those of the former reports on pubis length, ischium length, and IPI.     

Upper extremity kinematics during functional activities: three-dimensional studies in a normal pediatric population

Children with brachial plexus birth palsy, burns, cerebral palsy, spinal cord injury and upper limb malformations may have diminished ability to perform activities of daily living (ADLs) due to limited upper extremity (UE) motion. Three-dimensional (3D) imaging techniques provide a way to document multi-planar functional limitations in the UE. These techniques have not been routinely used for this purpose primarily due to a lack of standardized protocols stemming from the complex nature of UE motion. Before 3D techniques can be routinely used for quantitative analysis and determination of functional limitations, standard activities and nomenclature for UE motion must be determined, and normal arm motion defined. This study establishes a normative pediatric database of 3D kinematic values during selected ADLs, enabling future comparisons with pathologic movements. Regardless of their underlying condition, children with limited UE function and ADL performance can be studied using this protocol and compared with this age-matched normal population.     

Radiometry versus osteometry in sex assessment: a study of the Cretan radius

Sex estimation is vital for biological profiling, thus qualitative and quantitative methods have been developed for every skeletal part in humans. However, somehow the radius has been neglected. This study aims to develop a sex estimation method on radiographs of the radius applicable in situations when classical osteometry cannot be applied. A total of 103 left radii were used in this study. Three classical measurements (maximum length, head diameter and distal breadth) were taken on the dry bones. Digital radiographs of the same radii were taken using a portable X-ray machine (Technix TCA 4R PLUS). Eight landmarks are selected on the radiograph of the proximal and six on the radiograph of the distal radius, generating in total 43 linear distances. ANOVA detected three osteometric and 24 radiometric variables that differed significantly between males and females (p<0.05). Classical osteometry resulted in up to 91% classification accuracy while the best multivariate formula of the radiometric method gave 88% correct classification. The study proposes a rapid and inexpensive alternative method for sex screening based on digital radiographs of the radius, a method that could be particularly advantageous in cases of mass disasters with numerous mutilated and/or burnt bodies where maceration is not an option.     

Identifying sexual dimorphism in a paediatric South Indian population using stepwise discriminant function analysis

Anthropological research relies on skeletal and dental remains for the identification of species. Sexual dimorphism is the systematic difference in form between males and females of the same species. This study is designed to compute a new formula for sex determination using discriminant function analysis in the deciduous crown dimensions of a paediatric population of South Indian origin and to check its accuracy. The sample consisted of 93 females and 90 males of South Indian origin aged between 5 and 13 years. Alginate impressions of the upper dental arch were made and casts were poured immediately. A digital vernier calliper was used to obtain measurements. Teeth considered for measurement were deciduous maxillary canines and molars. Our study is a maiden attempt in considering diagonal measurements along with mesiodistal (MD) and buccolingual (BL) dimensions as predictor variables for sex determination. Statistical analysis was performed using the Statistical Package for the Social Science version 17.0 software. By using the Student t-test, the different predictor variables of teeth selected between male and females were found to be significant (p < 0.05). Highly significant sexual dimorphism was found in the mean MD dimension of maxillary right canine and right and left first molar, BL dimension of right first molar, distobuccal–mesiolingual of right and left first molar and right second molar and mesiobuccal–distolingual of right second molar. The percentage of sexual dimorphism in MD dimensions revealed that the right upper first molar was the most dimorphic tooth and the upper first molar of the left side was the least dimorphic of the six teeth studied. The present study found the level of sexual dimorphism in the deciduous crown dimensions of a selected group of South Indian population, which is sufficiently large to determine sex with an accuracy of 87.2–88% by discriminant function analysis. Hence the formula derived from the present study could be of some value in sex determination of paediatric populations of South Indian origin.     

Advances in three-dimensional reconstruction of the experimental spinal cord injury

Three-dimensional (3D) computer reconstruction is an ideal tool for evaluating the centralized pathology of mammalian spinal cord injury (SCI) where multiple anatomical features are embedded within each other. Here, we evaluate three different reconstruction algorithms to three-dimensionally visualize SCIs. We also show for the first time, that determination of the volume and surface area of pathological features is possible using the reconstructed 3D images themselves. We compare these measurements to those calculated by older morphometric approaches. Finally, we demonstrate dynamic navigation into a 3D spinal cord reconstruction.     

3D打印模型与CT三维重建影像辅助手术治疗复杂髋臼骨折的疗效

目的 探讨使用骨折3D打印模型辅助手术与参考骨折处CT 三维重建影像辅助手术治疗复杂髋臼骨折的疗效.方法 回顾性分析2017年10月-2020年9月汉中市中心医院骨关节外科手术治疗复杂髋臼骨折患者60例,男性36例,女性24例;年龄25～64岁,平均41.8岁.根据是否使用3D打印模型分为3D组(34例)及对照组(26...     

A new ambulatory system for comparative evaluation of the three-dimensional knee kinematics, applied to anterior cruciate ligament injuries

The aim of this study was to develop an ambulatory system for the three-dimensional (3D) knee kinematics evaluation, which can be used outside a laboratory during long-term monitoring. In order to show the efficacy of this ambulatory system, knee function was analysed using this system, after an anterior cruciate ligament (ACL) lesion, and after reconstructive surgery. The proposed system was composed of two 3D gyroscopes, fixed on the shank and on the thigh, and a portable data logger for signal recording. The measured parameters were the 3D mean range of motion (ROM) and the healthy knee was used as control. The precision of this system was first assessed using an ultrasound reference system. The repeatability was also estimated. A clinical study was then performed on five unilateral ACL-deficient men (range: 19–36 years) prior to, and a year after the surgery. The patients were evaluated with the IKDC score and the kinematics measurements were carried out on a 30 m walking trial. The precision in comparison with the reference system was 4.4°, 2.7° and 4.2° for flexion–extension, internal–external rotation, and abduction–adduction, respectively. The repeatability of the results for the three directions was 0.8°, 0.7° and 1.8°. The averaged ROM of the five patients’ healthy knee were 70.1° [standard deviation (SD) 5.8°], 24.0° (SD 3.0°) and 12.0° (SD 6.3°) for flexion–extension, internal–external rotation and abduction–adduction before surgery, and 76.5° (SD 4.1°), 21.7° (SD 4.9°) and 10.2° (SD 4.6°) 1 year following the reconstruction. The results for the pathologic knee were 64.5° (SD 6.9°), 20.6° (SD 4.0°) and 19.7° (8.2°) during the first evaluation, and 72.3° (SD 2.4°), 25.8° (SD 6.4°) and 12.4° (SD 2.3°) during the second one. The performance of the system enabled us to detect knee function modifications in the sagittal and transverse plane. Prior to the reconstruction, the ROM of the injured knee was lower in flexion–extension and internal–external rotation in comparison with the controlateral knee. One year after the surgery, four patients were classified normal (A) and one almost normal (B), according to the IKDC score, and changes in the kinematics of the five patients remained: lower flexion–extension ROM and higher internal–external rotation ROM in comparison with the controlateral knee. The 3D kinematics was changed after an ACL lesion and remained altered one year after the surgery.     

Sex estimation from discriminant function analysis of clavicular and sternal measurements: a forensic anthropological study based on examination of two bones of Northwest Indian subjects

The clavicle and the sternum are important bones of the anterior thoracic skeleton that are commonly found well preserved in forensic contexts. To assess the concurrent suitability of two bones of the same individual in forensic sex estimations, both clavicles and sternums were collected from 252 male and 91 female autopsy cadavers. This study’s bone dimensions were found to be significantly smaller than of subjects of other nationalities and also higher than previous Indian studies. Statistically significant sex differences were noticed in different dimensions of the two bones (p < 0.001). The univariate DFA found that the product index of the clavicle and combined sternal length were the best sex discriminating variables to identify the sex of about 85% of the cadavers. From the multivariate discriminant function analysis of all linear variables (DF: –18.664 + 0.107 (MCI–L) + 0.180 (MCC–R) +.045(MBL) – 0.071(MDL–L), the sex of 90.7% of the cadavers could be estimated correctly and this percentage was highest when either clavicular or sternal measurements were used in the analyses. The concurrent use of the two bones provided higher accuracy levels with lower sex biases than the individual use of either bone in univariate or multivariate analysis. The clavicle was found to be better and more reliable than the sternum for sex estimations in the current autopsy samples. Further studies are needed to corroborate or negate the findings of these investigations.     

Dynamic echo-planar MR imaging of the diaphragm for a 3D dynamic analysis

The purpose of this study was to prove the feasibility of 3D reconstructions of the diaphragm during the respiratory cycle using EPI sequences (EPI acquisition, 270 ms/image, on a healthy subject breathing spontaneously and at 0.1 Hz). Continuously recorded respiratory signal allowed for retrospective synchronization with respiratory phases for reconstruction of successive diaphragm surfaces using a specifically designed software. Displacements, area and volume changes of the diaphragm were quantified. Our measurements were comparable with the data in the literature. Reconstructed surfaces allowed in vivo diaphragm dynamic evaluation in terms of displacements, area and volume variations. EPI has adequate spatial and temporal resolution for studying diaphragm dynamics during natural breathing.     

Characterization of three-dimensional myocardial deformation in the mouse heart: an MR tagging study

PURPOSE: To develop a 3D MR tagging method that combines harmonic phase (HARP) and homogeneous strain analysis methods for quantification of regional myocardial wall motion in mice. MATERIALS AND METHODS: 3D tagged images were acquired from seven C57BL/6 mice. Intersecting tag points were reconstructed and 3D strains were quantified at apical, midventricular, and basal levels. Circumferential and radial strains quantified with 2D MR tagging were compared with those calculated from 3D tagged images. RESULTS: Our data showed significant heterogeneity in radial, circumferential, and shear strains. Longitudinal strain was more homogeneous. The circumferential-longitudinal shear strain, a unitless measure of ventricular torsion, was positive throughout the left ventricle. There were strong correlations between 2D and 3D studies at the basal and midventricular levels. CONCLUSION: This work demonstrates the feasibility of 3D characterization of cardiac function in mouse via the combination of HARP and homogeneous strain analysis.     

Sex differences in fingerprint ridge density in a Turkish young adult population: A sample of Baskent University

Fingerprints are considered to be one of the most reliable methods of identification. Identification of an individual plays a vital part of any medico-legal investigations. Dermatoglyphics is a branch of science that studies epidermal ridges and ridge patterns. Epidermal ridges are polygenic characteristics that form intrauterine 10–18 weeks and considered fully developed by the sixth month of fetal growth. Fingerprints are permanent morphological characteristics and criminal detection based on fingerprints is based on the principle that no two people can have identical fingerprints. Sex determination from fingerprints has been examined in different population. In this study we aimed to study fingerprint ridge density in Turkish population sample of Baskent University students. Fingerprints were obtained from 118 women, 88 men a total of 206 students aged between 17 and 28 years old by means of simple inking method. Fingerprints from all right and left hands fingers were collected in three different area of each. The ridges on fingerprints were counted diagonally on squares measuring 5 mm × 5 mm on radial, ulnar and inferior areas. The fingerprint ridge density in radial, ulnar and inferior areas and between sexes was compared statistically Mann Whitney U test and Friedman test. The ridge density was significantly greater in women in every region studied and in all fingers when compared to men. The fingerprint ridge density in the ulnar and radial areas of the fingerprints was significantly greater than the lower area. Fingerprint ridge density can be used by medico-legal examination for sex identification.     

Sexual dimorphism of the human sternum in a Maharashtrian population of India: a morphometric analysis

Determination of sex from human skeletal remains is an imperative element of any medicolegal investigation. Length of manubrium, length of mesosternum, and combined length of manubrium and mesosternum were measured in 115 sternums of confirmed sex (75 male and 40 female) for sexual dimorphism. Application of "the 50 rule" for the manubrium confirmed sex in 77.3% male and 77.5% female bones, while application of "the 81 rule" for the mesosternum confirmed sex in 73.3% male and 75% female bones accurately. Application of "the 131 rule" derived from the study for combined length of manubrium and mesosternum confirmed sex in 85.3% male and 77.5% female sternums correctly. This study confined to the Maharashtra region of western India is useful to determine the sex of the sternum when it is subjected for medicolegal skeletal examination.     

Analysis of 24 Y chromosomal STR haplotypes in a Chinese Han population sample from Henan Province,Central China

We analyzed haplotypes for 24 Y chromosomal STRs (Y-STRs), including 17 Yfiler loci (DYS19, DYS385a/b, DYS389I/II, DYS390, DYS391, DYS392, DYS393, DYS437, DY438, DYS439, DYS448, DYS456, DYS458, DYS635 and Y-GATA-H4) and 7 additional STRs (DYS388, DYS444, DYS447, DYS449, DYS522 and DYS527a/b) in 1100 unrelated Chinese Han individuals from Henan Province using AGCU Y24 STR kit systems. The calculated average gene diversity (GD) values ranged from 0.4105 to 0.9647 for the DYS388 and DYS385a/b loci, respectively. The discriminatory capacity (DC) was 72.91% with 802 observed haplotypes using 17 Yfiler loci, by the addition of 7 Y-STRs to the Yfiler system, the DC was increased to 79.09% while showing 870 observed haplotypes. Among the additional 7 Y-STRs, DYS449, DYS527a/b, DYS444 and DYS522 were major contributors to enhancing discrimination. In the analysis of molecular variance, the Henan Han population clustered with Han origin populations and showed significant differences from other Non-Han populations. In the present study, we report 24 Y-STR population data in Henan Han population, and we emphasize the need for adding additional markers to the commonly used 17 Yfiler loci to achieve more improved discriminatory capacity in a population with low genetic diversity.     

Computer-assisted identification of the central sulcus in patients with brain tumors using MRI

PURPOSE: To develop computer-assisted image processing to identify the central sulcus from the MRI data sets in patients with brain tumors. MATERIALS AND METHODS: All MR images were acquired with a 3.0 Tesla scanner by three-dimensional (3D) spoiled gradient recalled acquisition using the steady state (SPGR) gradient-echo sequence and short inversion time inversion-recovery fast spin-echo sequence. The sulci were extracted automatically from reconstructed two-dimensional images of the cortical surface of 30 patients with brain tumors, and the extracted sulci were scored according to matching of the accepted anatomical features of the central sulcus. The candidates with the three highest scores were then superimposed on the 3D images. The correct position of the central sulcus was agreed by two senior neurosurgeons and one neuroradiologist. RESULTS: One of the three candidates corresponded to the central sulcus identified by the manual segmentation method for all 60 affected and unaffected hemispheres in the 30 patients. The candidate with the highest score coincided with the central sulcus in 26 of the 28 unaffected hemispheres and in 28 of the 32 affected hemispheres. CONCLUSION: The proposed method of computer-assisted image processing can provide accurate guidance to identifying the central sulcus in patients with brain tumors.     

Anthropometric study of the external ear and its applicability in sex identification: assessed in an Indian sample

Ear prints have the potential for personal identification as the shape, size and orientation of the external ear are as individual as fingerprints. Several studies exist on ear dimensions in various populations; however, studies on Indians are sparse and none of these studies have explored the sex discrimination potential of ear morphometric variables. The present study included 300 subjects (150 males and 150 females) in the age range of 18–30 years originating from all over India. A digital anthropometric method was employed to measure ear length and breadth, base of auricle, lobe length and breadth. Further, the physiognomic ear index, lobe attachments and shape of ear were also assessed. The sex discrimination potential of all these variables was also evaluated. The right and left ears were mostly asymmetrical with respect to ear length, ear breadth, base of auricle. The ear length, breadth and base of auricle were larger in males than females while lobe length and breadth were larger in females as compared with males (chi square test, p ? 0.001). Additionally, the ear parameters gave a moderate to good sex identification accuracy ranging from 68–71% using discriminant function analysis.     

CT引导下中心静脉导管置管引流心包积液的临床分析

目的 探讨CT引导下应用中心静脉导管置管引流心包积液的临床可行性、操作安全性、具体穿刺方法及相关注意事项.方法 对114例心包积液患者随机分为CT引导组(A组),超声体表定位组(B组),比较两组平均穿刺成功时间、平均穿刺次数、穿刺成功率及并发症的发生率.结果 A组第1针穿刺成功率为96.6％,B组为78.6％,P＜0.05,在穿刺成功率上两组差异有统计学意义.总并发症发生率A组为3.4％,B组为16.1％.并发症的发生两组相比差异有统计学意义.结论 在CT引导下进行中心静脉导管置管引流心包积液,成功率高、不良反应少、引流彻底、方便注药.操作安全有效,值得在临床推广应用.