Determining the Timing and Mechanism of Bone Fracture in Bovine Bone

Trauma interpretation is one of the most essential and challenging areas offorensic anthropology. When examining bone fragments commonly encountered in real forensic anthropological casework, the ambiguity and difficulty assessing the trauma type and bone condition at the time of fracture is markedly more difficult. Traditional features used to distinguish bone condition and trauma type have included fracture surface texture and fracture angle, however, these features have not been explored in depth in terms their reliability and these observational categories remain poorly defined. In the current study, I examine fracture angles and surfaces produced from ballistic (115g 9mm FMJ and 147g HP ammunition) and blunt force trauma (10 lb. sledge hammer) on bovine long bones in different states of preservation (frozen, fresh, dry). Building on previous anthropological research and the mechanical literature, I attempt to refine the criteria of `smooth' and `rough / jagged' used to describe surface texture and attempt correlate the criteria to bone condition and trauma type. Using Microsil, a forensic casting material, I present a straightforward method for capturing and assessing surface information without the confounding features of color and moisture. Seven sampling sites were selected from each bone, four from the entrance / point of impact side and three from the exit / posterior to impact side. All fractures cast and measured were longitudinal or radial fractures. Results of this study indicate that fracture angle does not demonstrate a statistically significant relationship with cortical bone thickness, nor does it correlate with type of trauma or bone condition. The only statistically significant relationship was between fracture angle and bone condition for fracture angles from the impact side of blunt force trauma specimens. Fracture surface characteristics do diverge among bone conditions, but not for trauma type. Qualitatively, for a single specimen, fracture angle and fracture surface characteristics appear to have limited value in the assessment of bone condition and / or trauma type. It is recommended for the determination of bone condition and trauma type that fracture angle and surface texture be not be used when analyzing single bones. Other observations, such as impact sites and projectile entries and exits, in combination with taphonomic indicators like color, staining, and context should be relied upon to describe and determine trauma type and bone condition

Determining the Timing and Mechanism of Bone Fracture in Bovine Bone

Trauma interpretation is one of the most essential and challenging areas offorensic anthropology. When examining bone fragments commonly encountered in real forensic anthropological casework, the ambiguity and difficulty assessing the trauma type and bone condition at the time of fracture is markedly more difficult. Traditional features used to distinguish bone condition and trauma type have included fracture surface texture and fracture angle, however, these features have not been explored in depth in terms their reliability and these observational categories remain poorly defined. In the current study, I examine fracture angles and surfaces produced from ballistic (115g 9mm FMJ and 147g HP ammunition) and blunt force trauma (10 lb. sledge hammer) on bovine long bones in different states of preservation (frozen, fresh, dry). Building on previous anthropological research and the mechanical literature, I attempt to refine the criteria of `smooth' and `rough / jagged' used to describe surface texture and attempt correlate the criteria to bone condition and trauma type. Using Microsil, a forensic casting material, I present a straightforward method for capturing and assessing surface information without the confounding features of color and moisture. Seven sampling sites were selected from each bone, four from the entrance / point of impact side and three from the exit / posterior to impact side. All fractures cast and measured were longitudinal or radial fractures. Results of this study indicate that fracture angle does not demonstrate a statistically significant relationship with cortical bone thickness, nor does it correlate with type of trauma or bone condition. The only statistically significant relationship was between fracture angle and bone condition for fracture angles from the impact side of blunt force trauma specimens. Fracture surface characteristics do diverge among bone conditions, but not for trauma type. Qualitatively, for a single specimen, fracture angle and fracture surface characteristics appear to have limited value in the assessment of bone condition and / or trauma type. It is recommended for the determination of bone condition and trauma type that fracture angle and surface texture be not be used when analyzing single bones. Other observations, such as impact sites and projectile entries and exits, in combination with taphonomic indicators like color, staining, and context should be relied upon to describe and determine trauma type and bone condition

Secular Change in the Femur Diaphyseal Biomechanical Properties of American Whites

Over the past two centuries there have been documented secular changes in stature, weight, body proportions, and skeletal maturation rates in the United States. These changes along with a more sedentary lifestyle are likely reflected in femur morphology. Here we examine secular changes in diaphyseal cross-sectional size, shape, area, robusticity, and rigidity at midshaft and subtrochanteric of the femur using 395 adult white females and males from the United States born between the 1850s and the 1970s. The effect of secular change was controlled for an age effect. We also examine the relationship between femur length (proxy for stature) and femur head diameter (proxy for body weight) on measurements of diaphyseal size and biomechanical properties. The femur morphology of Americans born in the twentieth century reflects the combination of changes in stature, body build, and activity levels. Both sexes show significant changes in femur midshaft shape due primarily to a decrease in the mediolateral diameter. There are no significant changes at subtrochanteric in size or biomechanical properties in either sex after controlling for age variation. The results suggest that the changes in femur midshaft shape are primarily associated with a decrease in activity. The stability of the subtrochanteric dimensions and femur anteroposterior diameter may reflect a combination of decreased activity with a corresponding increase in femur length (moment arm) and a decrease in body breadth

Elder abuse: evaluating the potentials and problems of diagnosis in the archaeological record

The elderly are the most neglected demographic in archaeology. In today's youth-obsessed society, the elderly are consistently denigrated, particularly those perceived to be physically or mentally frail. A related and growing concern in contemporary populations is the physical abuse of the elderly, believed to be an escalating phenomenon. This study is the first to examine the risk factors, social context and patterns of trauma associated with elder abuse in the present, with the aim of providing diagnostic criteria to apply to past societies. The utility of skeletal evidence in the identification of violent trauma has been detailed in cases of child and intimate partner abuse, both modern and archaeological. Investigating the skeletal evidence for elder abuse is potentially more complex because of the confounding physiological effects of the ageing process, lack of clinical research and contemporary ageist attitudes towards older people. Within the clinical and bioarchaeological literature, there has been a tendency to dismiss injuries in older individuals as the product of accident or opportunistic violence. A proportion of elder members of past societies is likely to have been victims of abuse and family violence. While there are no pathognomonic skeletal features of elder abuse, multiple injuries to the bones of the following are indicative: cranium, maxilla-facial region, dentition, cervical vertebrae, clavicles, ribs and spiral fractures to the humeri. Attention is also drawn to decubiti as indirect skeletal indicators of immobility and possibly neglect. Archaeological context is important to consider, including non-normative burials or those indicating social marginalisation. Bioarchaeological evidence has the potential to provide a long-term perspective on the care and treatment of past elders