The Utility of Skeletal and Surgical Features for the Personal Identification Process: A Pilot Study

This pilot study provides a conceptual framework for the application of the anthropological analysis of skeletal features and surgical interventions for the purpose of identification in cases of unknown deceased individuals with unavailable fingerprint, genetic or odontological antemortem data. The study sample includes 276 individuals with known demographic and clinical information from the Italian CAL Milano Cemetery Skeletal Collection. In the sample, 124 (45%) individuals showed one or more skeletal features that may be potentially individualizing. Of these, 79% showed two and more features, which occurred in a multitude of different combinations. Skeletal findings may provide useful postmortem information that can be compared with antemortem witness statements and clinical imaging. However, more research into the utility of dry bone findings and the availability of comparative material, including imaging, and epidemiological data needs to be undertaken before skeletal features can be implemented into identification protocols and databases.     

Positive Personal Identification of Human Remains Based on Thoracic VertebralMargin Morphology

Abstract: Radiography has long been used by anthropologists to establish positive personal identification of human remains in forensic cases. These methods have been largely ad hoc and depend upon specific congenital or pathological bone markers. Court rulings, such as Daubert and Mohan have, however, pushed the discipline toward more statistically supportable methods of identification. This study describes the use of normal morphological variation of the thoracic vertebrae to identify human remains. Radiographs from healthy, male individuals, aged 18–55 were examined to identify normally varying features of vertebral morphology. The frequency of occurrence of these features was calculated, tested, and found to be stable in the given sample. The frequencies were compared to establish which sets of traits varied independently of one another. Finally, unknown radiographs were compared to known samples to test the applicability of this method in determining positive identification, with 21 of 24 (87.5%) unknown radiographs positively identified.     

Nonmetric sex determination from the distal and posterior humerus in black and white South Africans

The successful identification of human skeletal remains relies on proven diagnostic techniques for sex determination. This research utilized 608 individuals from South Africa (420 men, 188 women) to conduct a blind nonmetric determination of sex from three features of the distal humerus: olecranon fossa shape, angle of the medial epicondyle, and trochlear extension. A scoring system between males and females was implemented, and the aggregate score of the three features determined the estimated sex of the skeletal element in question. With all features combined, black and white South Africans were categorized successfully as either male or female 75.5% (77% accuracy rate for females, 74% accuracy rate for males). This classification rate is lower than what was found in previous studies, but suggests that characteristics of the distal humerus are still quite valuable when estimating skeletal sex. More research is needed to assess reasons for the differential expression of these traits in different populations and to determine whether the method is nonpopulation specific.     

Survival of Atherosclerotic Calcifications in Skeletonized Material: Forensic and Pathological Implications

Atherosclerosis is a chronic inflammatory disease creating calcifying plaques in the arterial walls. Because its paleopathological diagnosis remains little studied on skeletal remains, its impact on forensic and archeological data is completely underestimated. Here, 24 skeletal remains from the Milano Cemetery Skeletal Collection have been studied to evaluate the chance of atherosclerotic calcification survival, retrieval, and identification. Through direct comparison with a known autopsy collection and literature, the identification and categorization of several types of calcifications were performed. Clothing elements such as tights or socks played a definitive role in the preservation of the calcifications; hence they are more likely to be found in forensic cases than in archeological ones. Therefore, vascular calcifications are possible to collect and identify in skeletal remains if sufficient care is given to their recovery. Consequently and as markers of the disease, such identification can provide valuable pathological information for forensic and archeological cases.     

Positive personal identity of skeletonized remains using abdominal and pelvic radiographs.

Premortem and postmortem radiographs of the chest and abdomen are often available for comparison and provide a basis for making or rejecting an identification. The case reported here exemplifies the way that individualizing features, such as contours of bony elements, skeletal anomalies, and radiodensities and radiolucencies, are used in establishing personal identity.     

Disaster victim identification: new applications for postmortem computed tomography

Abstract:  Mass fatalities can present the forensic anthropologist and forensic pathologist with a different set of challenges to those presented by a single fatality. To date radiography has played an important role in the disaster victim identification (DVI) process. The aim of this paper is to highlight the benefits of applying computed tomography (CT) technology to the DVI process. The paper begins by reviewing the extent to which sophisticated imaging techniques, specifically CT, have been increasingly used to assist in the analysis of deceased individuals. A small scale case study is then presented which describes aspects of the DVI process following a recent Australian aviation disaster involving two individuals. Having grided the scene of the disaster, a total of 41 bags of heavily disrupted human remains were collected. A postmortem examination was subsequently undertaken. Analysis of the CT images of all body parts ( n  = 162) made it possible not only to identify and side differentially preserved skeletal elements which were anatomically unrecognizable in the heavily disrupted body masses, but also to observe and record useful identifying features such as surgical implants. In this case the role of the forensic anthropologist and CT technology were paramount in facilitating a quick identification, and subsequently, an effective and timely reconciliation, of body parts. Although this case study is small scale, it illustrates the enormous potential for CT imaging to complement the existing DVI process.     

Skull-photo superimposition and border deaths: identification through exclusion and the failure to exclude

We report on the application of video skull-photo superimposition as an identification method in a case from Ajo, Arizona in which five individuals died after crossing into southern Arizona from Mexico. Initial analyses at the Pima County Forensic Science Center in Tucson, Arizona determined that the disarticulated skeletal remains represented two adult Hispanic males and three adult Hispanic females. Based on biological profiles, both the males and one of the females were tentatively identified and assigned names. The other two females were too similar in age and height, making skeletal separation and identification difficult. As a result, the Michigan State University Forensic Anthropology Laboratory assisted in the identification efforts by performing video skull-photo superimposition on the two unknown females. The skulls were compared to a photograph reported to be one of the missing females. By evaluating facial proportionality and by comparing a number of morphological features of the face and skulls, one skull was excluded as a possible match and one skull was not excluded as a match to the antemortem photo. Because this case was presumed to be a closed disaster, the exclusion of one skull and the failure to exclude the other represented circumstantial identifications.     

Classification of Pelvic Ring Fractures in Skeletonized Human Remains

Pelvic ring fractures are associated with high rates of mortality and thus can provide key information about circumstances surrounding death. These injuries can be particularly informative in skeletonized remains, yet difficult to diagnose and interpret. This study adapted a clinical system of classifying pelvic ring fractures according to their resultant degree of pelvic stability for application to gross human skeletal remains. The modified Tile criteria were applied to the skeletal remains of 22 individuals from the Cleveland Museum of Natural History and Universidad Nacional Autónoma de México that displayed evidence of pelvic injury. Because these categories are tied directly to clinical assessments concerning the severity and treatment of injuries, this approach can aid in the identification of manner and cause of death, as well as interpretations of possible mechanisms of injury, such as those typical in car-to-pedestrian and motor vehicle accidents.     

Radiographic Identification Using Midline Medical Sternotomy Wires,

Forensic anthropologists are regularly asked to assist with the identification of unknown individuals using comparative medical radiography. This study addressed the use of midline medical sternotomy wires as a means for personal identification. Antemortem and postmortem radiographic comparisons were completed by 46 professional forensic anthropologists and anthropology graduate students familiar with comparative medical radiography as a technique for assessing identification. Participants were asked to make five radiographic matches from a pool of 20 radiographs. Participants also completed an anonymous survey detailing their education level and experience making radiographic comparisons. Participants were 99.5% accurate in matching the radiographs. Sensitivity was 98.7%, and specificity was 99.7%. Logistic regression analysis found no statistically significant differences in the participants' ability to make a correct match. As the high accuracy rates indicate, the shape, size, and various characteristics of the sternotomy wires are individualizing and can confidently be used when assisting with personal identification cases.     

A radiographic assessment of pediatric fracture healing and time since injury

Past studies and pediatric bone physiology indicate that younger individuals may heal at a faster rate. Additionally, in adults upper limb fractures heal faster than lower limb fractures; this trend is expected for pediatric fractures. This study aims to evaluate and compare rates of fracture repair in children based on age and skeletal element. Six stages are used to describe the bone repair process in 294 radiographs of tibial and radial fractures from 107 infants and young children. Healing rates are examined using ANOVA and Welch's t-test with a 95% confidence interval. Results indicate that younger individuals spend less time at stage 1, suggesting a delay in the start of healing. Furthermore, forearm fractures heal faster than leg fractures at stages 2 and 3, suggesting a role in the osseous reaction of bone healing. The healing schedule presented may allow the timing of injuries to be estimated from radiographs.     

Identifying Southwest Hispanics using nonmetric traits and the cultural profile

Due to the increasing number of Southwest Hispanics in the United States, as well as the overwhelming number of foreign nationals that die every year trying to enter the United States along the southern United States border with Mexico, new methods for classifying individuals have been established at the Pima County Office of the Medical Examiner in Tucson, Arizona (PCOME). For each of the past 5 years, the PCOME has investigated a record number of deaths associated with these border crossings. The overwhelming majority of the identified decedents are Mexican Nationals. However, approximately 25% of these undocumented border crossers have yet to be identified, making it clear that improved methods for human identification are greatly needed. The first goal of this paper is to delineate the suite of skeletal nonmetric traits utilized in assessing Southwest Hispanic ancestry at the PCOME. This suite of nonmetric traits has proven to be an effective component in establishing the "biological profile" of unknown individuals in these cases. The second goal of this paper is to introduce methods used at the PCOME to establish the "cultural profile" of individuals in these cases. The "cultural profile" is a set of identification criteria that include: the geographic context of recovery, personal effects, dental health, and cultural accoutrements. Establishing the "cultural profile" in these cases is essential in identifying individuals as foreign nationals who have died trying to cross the border.     

Sexual dimorphism in America: geometric morphometric analysis of the craniofacial region

One of the four pillars of the anthropological protocol is the estimation of sex. The protocol generally consists of linear metric analysis or visually assessing individual skeletal traits on the skull and pelvis based on an ordinal scale of 1-5, ranging from very masculine to very feminine. The morphologic traits are then some how averaged by the investigator to estimate sex. Some skulls may be misclassified because of apparent morphologic features that appear more or less robust due to size differences among individuals. The question of misclassification may be further exemplified in light of comparisons across populations that may differ not only in cranial robusticity but also in stature and general physique. The purpose of this study is to further examine the effect of size and sex on craniofacial shape among American populations to better understand the allometric foundation of skeletal traits currently used for sex estimation. Three-dimensional coordinates of 16 standard craniofacial landmarks were collected using a Microscribe-3DX digitizer. Data were collected for 118 American White and Black males and females from the W.M. Bass Donated Collection and the Forensic Data Bank. The MANCOVA procedure tested shape differences as a function of sex and size. Sex had a significant influence on shape for both American Whites (F = 2.90; d.f. = 19, 39; p > F = 0.0024) and Blacks (F = 2.81; d.f. = 19, 37; p > F = 0.0035), whereas size did not have a significant influence on shape in either Whites (F = 1.69; d.f. = 19, 39; p > F = 0.08) or Blacks (F = 1.09; d.f. = 19, 37; p > F = 0.40). Therefore, for each sex, individuals of various sizes were statistically the same shape. In other words, while significant differences were present between the size of males and females (males on average were larger), there was no size effect beyond that accounted for by sex differences in size. Moreover, the consistency between American groups is interesting as it suggests that population differences in sexual dimorphism may result more from human variation in size than allometric variation in craniofacial morphology.     

Surgical Sutures as a Means of Identifying Human Remains*

Abstract: The Food and Drug Administration does not require surgical sutures to be tracked by manufacturer, physician, or patient; thereby, surgical sutures have been of little use to forensic practitioners who are tasked with establishing a positive identification with biological evidence. This study demonstrates the investigative process used to pinpoint suture manufacturers by presenting a case where surgical sutures were a distinctive characteristic that aided in the positive identification of skeletal remains. The suture’s manufacturer, construction material and structure, size, and medical use was determined by contacting a local surgical suture and orthopedic implant manufacturer and utilizing publicly available manufacturer websites, which provide catalogs and specific product details. This research was one of many lines of evidence used to establish the positive identification of a 47‐year‐old male.     

Anthropological and Radiographic Comparison of Antemortem Surgical Records for Identification of Skeletal Remains*

Abstract: This case review illustrates the important contributions of forensic archeological methods and forensic anthropological analysis to the identification of found skeletal remains. After reassociation of skeletal remains found in two locations, anthropological analysis provided the basis for a presumptive identification and a request for antemortem medical records. Partial DNA profiles were supportive but not conclusive and antemortem dental records were not available. Comparison of antemortem traumas, skeletal morphology, and surgical artifacts with antemortem radiographs and surgical records led to positive identification of an individual missing for almost a decade.     

Discrete Traits of the Sternum and Ribs: A Useful Contribution to Identification in Forensic Anthropology and Medicine

During forensic anthropological investigation, biological profile is determined by age, sex, ancestry, and stature. However, several individuals may share the same profile. Observation of discrete traits can yield useful information and contribute to identification. This research establishes the frequency of discrete traits of the sternum and ribs in a modern population in southern France, using 500 computer tomography (CT) scans of individuals aged 15–60 years. Only discrete traits with a frequency lower than 10% according to the literature were considered, a total of eight traits. All scans examined were three‐dimensional (3D) volume renderings from DICOM images. In our population, the frequency of all the discrete traits was lower than 5%. None were associated with sex or age, with the exception of a single trait, the end of the xiphoid process. Our findings can usefully be applied for identification purposes in forensic anthropology and medicine.     

Virtual determination of sex: metric and nonmetric traits of the adult pelvis from 3D computed tomography models

Examination of the adult os coxae and sacrum is one of the most common methods of sex estimation from bone. Medical imaging, such as computed tomography (CT), provides the opportunity for three-dimensional (3D) imaging of the skeleton from clinical scans of known individuals in situ. In this study, a randomly selected subset of abdominopelvic CT-derived models were used to evaluate simple, repeatable metric methods of sex estimation based on a combination of obstetric measurements and the traditionally nonmetric Phenice-derived traits. A four-variable discriminant function for sex estimation was developed based on statistical analyses. Overall, the cross-validated accuracy of this method was 100%, with inter-observer error showing an average of only 2.2%. Comparative analysis was run on the data set using FORDISC 3.0. This study shows that current sex determination standards from the pelvis should be updated to include more in vivo data to increase the accuracy of identification.     

Improving Nonmetric Sex Classification for Hispanic Individuals

Current techniques used by forensic anthropologists for the identification of unknown human skeletal remains have largely been created using U.S. Black and White samples. When applied to Hispanics, these techniques perform poorly and can lead to misclassifications; consequently, there is an imperative need for population‐specific standards for Hispanics. This research examines the classification accuracies obtained by the original Walker (Am J Phys Anthropol, 136, 2008) and Klales et al. (Am J Phys Anthropol, 149, 2012) methods for nonmetric sex estimation and provides recalibrated regression equations specifically for Hispanics. Ordinal data were collected for five skull and three pelvic traits from a sample of 54 modern Hispanic individuals. Recalibration of the Klales et al. equation improved accuracy (90.3% vs. 94.1%), while recalibration of the Walker method equation decreased accuracy (81.5% vs. 74.1%), but greatly improved sex bias (22.2% vs. ?7.4%), thereby making the recalibrated equations more appropriate for use with Hispanics.