Determination of Death by Suicide or Homicide through Hyoid Bone Fracture Patterns

Voiceover

Presenter(s)

Roger Sherman

Abstract or Description

Distinguishing between a true suicidal hanging and a homicidal strangulation with subsequent simulated hanging is difficult even for highly trained professionals. A possible way to distinguish between the two modes of death is through examination and comparison of the neck structures, particularly the hyoid bone and noticeable fractures. Not much work has been done on identifying differences in fracture patterns, as most investigators search for obvious signs that indicate the mode of death, such as ligature marks or defensive wounds. The purpose of this research was to determine whether the hyoid bone fractures alone can be used to determine whether a victim committed suicide, or the aggressor staged a suicide postmortem when more obvious types of evidence are missing, and to determine whether a model-based approach is a valid simulation type for fracture interpretation. Two male and two female hyoid bones were harvested from cadavers and cleaned using an aqueous sodium carbonate solution. The processed bones were then scanned using a clinical cone beam CT imaging system to develop STL files for use in 3D printing. Six models of each bone were printed using an Ender-3 printer and FibreTuff_® polymer. The models were then embedded into collagen gel and crushed at front facing and side profile angles using a Torbal^® Odyssey test stand and force gauge. Slight variations in the force required to fracture the models were found, but enough similarities to literature values were present to allow for the model-based approach to be considered a viable method, allowing for simulations to be performed and proving that a model-based approach is a valid testing method. The information gathered about hyoid bone fracture patterns could allow for better detection of staged suicides and provide more resources for investigators to determine the mode of death.

Keywords: hyoid, manner of death, strangulation

Mentor

Pamela Marshall