Effects of input energy and impactor shape on cranial fracture patterns.

This study documents relationships between input energy, impactor shape, and the formation of fractures in human crania. Parietal impact experiments (n = 12) were performed at 67% higher input energy compared to previously reported experiments. Fracture origins, characteristics, and locations were compared at two input energy levels with three impactor shapes (focal "hammer", flat "brick", and curved "bat").

Investigating reverse butterfly fractures: An experimental approach and application of fractography.

Butterfly fractures are expected to form with the transverse portion on the tension side and the wedge portion on the compression side of a bent bone, however wedges have also been observed in the reverse orientation and are reported to be frequent in concentrated 4-point bending. To investigate how these fractures form, concentrated 4-point bending experiments were performed on nine human femora and documented using high-speed video. Videos showed the wedge portion formed as fracture initiated in tension, branched obliquely, then curved to terminate on the tension face.

Effects of age and rate of twist on torsional fracture patterns in infant porcine femora.

Objective: Long bone fractures are a common injury in the pediatric population. Differentiation between abusive, or non-accidental trauma, and accidental trauma in children remains challenging for forensic practitioners. A recent clinical-based study was able to separate pediatric abusive from accidental trauma based on femoral fracture pattern using the ratio of fracture length over bone diameter (fracture ratio), as determined from radiographic analysis of this fractured bone.

Experimental investigation of cranial fracture initiation in blunt human head impacts.

The relationship between the point of blunt impact and the location of cranial fracture initiation continues to be poorly understood. The current study used high-speed video to capture cranial fracture initiation and propagation in impact experiments on twelve unembalmed, intact human cadaver heads. Video footage provided direct evidence that blunt cranial impacts can produce linear fractures initiating peripheral to the impact site.

The Role of Interface Shape on the Impact Characteristics and Cranial Fracture Patterns Using the Immature Porcine Head Model,

The forensic literature suggests that when adolescents fall onto edged and pointed surfaces, depressed fractures can occur at low energy levels. This study documents impact biomechanics and fracture characteristics of infant porcine skulls dropped onto flat, curved, edged, and focal surfaces. Results showed that the energy needed for fracture initiation was nearly four times higher against a flat surface than against the other surfaces.

A method of determining bending properties of poultry long bones using beam analysis and micro-CT data.

While conventional mechanical testing has been regarded as a gold standard for the evaluation of bone heath in numerous studies, with recent advances in medical imaging, virtual methods of biomechanics are rapidly evolving in the human literature. The objective of the current study was to evaluate the feasibility of determining the elastic and failure properties of poultry long bones using established methods of analysis from the human literature. In order to incorporate a large range of bone sizes and densities, a small number of specimens were utilized from an ongoing study of Regmi et al.