Norman J. Sauer

Radiographic human identification using bones of the hand: a validation study.

The 1993 Supreme Court case Daubert v. Merrell-Dow Pharmaceuticals, Inc. underscores the importance of validating forensic science techniques. This research examines the validity of using posterior-anterior radiographs of the hand to make positive identifications of unknown human remains. Furthermore, this study was constructed to satisfy the requirements of Dauberts guidelines of scientific validity by establishing a standard methodology for hand radiograph analysis, testing the technique, and noting rates of error. This validation study required twelve participant examiners from the forensic science community, working independently, to attempt to match 10 simulated postmortem radiographs of skeletonized hands to 40 simulated antemortem radiographs of fleshed cadaver hands. The overall accuracy rate of the twelve examiners was 95%, while their collective sensitivity and specificity were 95% and 92%, respectively. However, the accuracy of each examiner was related to the amount of radiological training and experience of the observer. Six Ph.D. forensic anthropologists and four experienced forensic anthropology graduate students correctly identified all the matches. Participant examiners noted bone morphology, trabecular patterns of the proximal and middle phalanges, and distinctive radiopaque and radiolucent features as the anatomical features that aided the identification process. The hand can be an important skeletal element for radiographic positive identification because it contains 27 individual bones for comparative analysis.

Evaluation of Postdepositional Changes in the Trace Element Content of Human Bone

A prerequisite to dietary reconstruction based on the trace element content of disinterred bone is the evaluation of postdepositional, or diagenetic, changes in the levels of trace elements contained in the bone. This study describes one method of assessing trace element permeation in disinterred bones from the Black Earth site, Illinois. The levels of several trace elements were determined in 50 samples of bone and associated soil. Correlation coefficients were calculated to evaluate the degree to which variation in the bone levels corresponds to variation in the soil levels. The results suggest that no significant postdepositional exchange of Zn and Mn had occurred at the Black Earth site. Other methods of evaluating permeation and leaching are discussed.

The Effects of Aging on the Comparability of Antemortem and Postmortem Radiographs

To study the effects of aging on the ability to make positive identifications from radiographs of the postcranial axial skeleton, we collected early and later exposed abdominal X-rays from five patients whose period of treatment spanned from ten to twenty-three years. Corresponding lumbar vertebrae from each pair of radiographs were compared for similarities and differences in several of the criteria that have been reported as useful for individualization. These include shapes of the bodies, spinous processes, transverse processes, pedicles, and osteophytic extrusions. It is our conclusion that even though bone is a flexible tissue and changes constantly during life, aspects of the criteria chosen are quite stable and that even after two-and-a-half decades the ability to make positive identifications from postcranial axial material is not necessarily diminished.

A Radiographic Assessment of Pediatric Fracture Healing and Time Since Injury

Abstract:  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.

Symmetrical fracturing of the skull from midline contact gunshot wounds: reconstruction of individual death histories from skeletonized human remains.

This paper reports a bilaterally symmetrical cranio-facial fracture pattern that is observed in self-inflicted, midline gunshot wounds. Five cases of self-inflicted gunshots wounds are presented as follows: two high-powered rifle cases, two shotgun cases, and one handgun case. In all five cases the remains were either decomposing or skeletonized and submitted to forensic anthropologists. Following identification, the main focus of the anthropological examination was the analysis of perimortem trauma to the skeleton. In each case, the skull was submitted in a highly fragmented state. Nevertheless, by focusing on the pattern of perimortem cranio-facial fractures, the anthropologists contributed key information regarding the circumstances of death. The observed symmetrical cranio-facial fracture patterns in the above cases are described in detail and interpreted. The specific location of the linear fractures is discussed, as well as the theoretical rationale behind the location in terms of skeletal architecture, such as buttresses, struts, and sutures. The interpretive framework provided by this paper may prove helpful to others who are faced with similar cases of cranio-facial fracturing.

The Assymetrical Remodelling of Two Neurosurgical Burr Holes: A Case Study

A human skull identified as that of a 16-year-old female who had been reported missing about 3 years before the discovery of the specimen displayed evidence for the asymmetrical remodelling of bilateral neurosurgical burr holes. While one of the holes retained its original size and shape, gross evidence for the contralateral lesion had virtually disappeared. Initially, the open lesion was mistakenly suspected to be a recent bullet hole.

Evolutionary aspects of bone health

The period during which our human ancestors evolved is miniscule in relation to the evolutionary record of all living things. However, the speed with which the human species changed is unique among animals. This article reviews basic evolutionary forces as well as the timeline from the first appearance of early hominids through the modern age. The distinctive feature of human evolution is the combination of biology and culture that characterizes human adaptation. Presumably, the need for specific skeletal characteristics (e.g., size, shape, density) changed as early hominids experienced major shifts in adaptation. These shifts include expansion from the tropics to a wide range of environments; transition from hunting and gathering to food production; change from physically active lifestyles to relative sedentism; and increase in life expectancy. These changes can be related in some ways to the modern problem of osteoporosis. An understanding of mans evolutionary past holds important lessons and provides insight into safeguarding this aspect of health as man moves into the new millennium.

Testing the Demirjian and the international Demirjian dental aging methods on a mixed ancestry urban American subadult sample from Detroit, MI.

Abstract:  This paper tests the Demirjian and international Demirjian dental aging methods for forensic use when ancestry and ethnicity are unknown. A radiographic sample of 187 boys and girls was collected from the Department of Pediatric Dentistry at the University of Detroit Mercy and aged using both methods. The total sample and the sample by age categories (young, middle, and old) were analyzed using t‐tests. The Demirjian method was found to better estimate age to a statistically significant degree for the total sample, as well as the middle and old age categories. The young category was aged better using the international Demirjian method. The results indicate that while the Demirjian method accurately estimates age, caution must be used with the method. Further research is needed to determine whether the international Demirjian method can be used for forensics in the U.S.

Evolutionary aspects of bone health: development in early human populations.

The period during which our human ancestors evolved is miniscule in relation to the evolutionary record of all living things. However, the speed with which the human species changed is unique among animals. This article reviews basic evolutionary forces as well as the timeline from the first appearance of early hominids through the modern age. The distinctive feature of human evolution is the combination of biology and culture that characterizes human adaptation. Presumably, the need for specific skeletal characteristics (e.g., size, shape, density) changed as early hominids experienced major shifts in adaptation. These shifts include expansion from the tropics to a wide range of environments; transition from hunting and gathering to food production; change from physically active lifestyles to relative sedentism; and increase in life expectancy. These changes can be related in some ways to the modern problem of osteoporosis. An understanding of mans evolutionary past holds important lessons and provides insight into safeguarding this aspect of health as man moves into the new millennium.

Medicolegal investigation of an eighteenth century homicide

The skeleton of an adult man, recovered from an eighteenth century French fort site in Indiana, exhibited a series of sharp force wounds. The lesions, three cranial and one postcranial, had apparently been made by a heavy metal instrument similar to one of the European ax heads discovered elsewhere at the site. In this paper we describe the wounds, argue that the instrument used to create them was a European ax, and offer the opinion that the manner of death in this case was homicide.