Fracture pattern interpretation in the skull: differentiating blunt force from ballistics trauma using concentric fractures

There have been several anthropological studies on trauma analysis in recent literature, but few studies have focused on the differences between the three mechanisms of trauma (sharp force trauma, blunt force trauma and ballistics trauma). The hypothesis of this study is that blunt force and ballistics fracture patterns in the skull can be differentiated using concentric fractures. Two-hundred and eleven injuries from skulls exhibiting concentric fractures were examined to determine if the mechanism of trauma could be determined by beveling direction. Fractures occurring in buttressed and non-buttressed regions were examined separately. Contingency tables and Pearson's Chi-Square were used to evaluate the relationship between the two variables (the mechanism of trauma and the direction of beveling), while Pearson's r correlation was used to determine the strength of the relationship. Contingency tables and Chi-square tests among the entire sample, the buttressed areas, and the non-buttressed areas led to the null hypothesis (no relationship) to be rejected. Pearson's r correlation indicated that the relationship between the variables studied is greater than chance allocation.     

Fracture patterns on the infant porcine skull following severe blunt impact

The objective of this study was to document patterns of fracture on infant porcine skulls aged 2-28 days (n = 57) because of a single, high energy blunt impact to the parietal bone with rigid (nondeformable) and compliant (deformable) interfaces. Fracture patterns were mapped using Geographic Information System software. For the same generated impact force, the rigid interface produced more fractures than the compliant interface for all ages. This study also showed that this increased level of impact energy versus an earlier study using a lower energy resulted in new sites of fracture initiation and also caused previously defined fractures that propagate into an adjacent bone. Several unique characteristics of bone and diastatic fracture were documented as a function of specimen age, impact energy, and interface. These data describe some baseline characteristics of skull fracture using an animal model that may help guide future studies from forensic case files.     

Suicide by blunt force trauma

Suicide by self-inflicted blunt force injury is rare. The authors report a case of a 48-year-old man who initially appeared to have died of a homicidal beating. The pertinent autopsy findings consisted of blunt force closed head injury combined with numerous cutaneous abrasions and contusions of the entire body. Further inquiries confirmed a medical history of paranoid schizophrenia and a previous attempt at suicide. This case represents an extreme example of severe blunt trauma sustained during fatal self-mutilation and masquerading as a homicide. It also underscores the importance of correlating a thorough background investigation with autopsy findings in determining the appropriate manner of death.     

Experimental studies of skull fractures in infants

According to pediatric statements, falls from a standing position may cause skull fractures in infants without specific symptoms. Nearly every infant has at some time fallen from the changing table or the baby carriage, etc. From the forensic aspect it is the duty of experts to discuss the "battered child syndrome." Evidence given by the defendants concerning the height of the fall are unreliable. Experimental test series concerned with the stumbling height (82 cm in free fall) and three various types of floor-stone, carpet, and foam-backed linoleum -were carried out. In each case skull fractures were seen. In three cases the fractures crossed the sutures. Conclusions: (1) Each fall of an infant from the height of a table may cause a skull fracture, which may lead to death; (2) when child mishandling is suspected, all circumstances must be taken into consideration.     

Cardiac rupture following blunt trauma

A case of cardiac rupture following blunt trauma with no additional injuries is described. This can be a difficult diagnosis because of the presence of additional injuries and the lack of clinical symptoms. Here, there was a rupture of the pericardium, all chambers of the heart and the thoracic aorta.     

Ring fractures of the base of the skull

Besides complete ring fracture, also incomplete fractures open to the front, back, or side(s) are discussed on the basis of 61 ring fractures of the base of the skull. The fractures were found in casualties from traffic accidents (car passengers, cyclists and motorcyclists, pedestrians), after falls and other accidents. In traffic accidents, compression, traction, hyperextension, extreme lateral movements, and torsional forces can lead to ring fractures. In falls, compression and traction are the main forces. A fall in one plane is also capable of producing an incomplete ring fracture. Incomplete ring fractures may show lateral emphasis. The greater fracture length is found on the impact side (e.g., in falls). In contrast to complete ring fractures, incomplete ring fractures are compatible with longer survival times. Ring fractures are to be classified under direct fractures. This does not exclude the possibility that overall deformations of the skull with bursts can partly determine the course of the fracture.     

Classification of fractures of the skull vault bones

The proposed classification of fractures of the skull vault bones is based on fracture morphogenesis. Russian and foreign published data on skull vault fractures and the authors' own observations allowed some analogies and helped develop a new classification.     

Homicide by blunt force in 2 Scandinavian capitals

In the Oslo and Copenhagen areas, 77 instances of blunt force homicides were committed from 1985-1994, accounting for 18% of all homicides in that 10-year period. Fifty-four (70%) of the victims were male, often killed by an acquaintance during a fight. Almost 70% of the female victims were killed in their own home, whereas that was the case for only 30% of the male victims. The majority of the victims (of both sexes) had been hit in more than 1 region of the body. A female offender was encountered in 4 instances; none of their victims were children. Of the 3 children in the blunt force victim group, 2 were battered children. Many of the victims with a blood alcohol level of 0 turned out to have lived for some time after the injury.     

Discrimination of falls and blows in blunt head trauma: systematic study of the hat brim line rule in relation to skull fractures

In the discrimination of falls from blows in blunt head trauma, the hat brim line rule is one of the most often used criteria. The present study assesses the validity of the hat brim line rule for skull fractures and looks at other possible criteria. All autopsy cases were retrospectively analyzed on a 5-year period. Cases selected consisted of downstairs falls (n = 13), falls from one's own height (n = 23), and homicidal blows (n = 44). Results show that fractures above the hat brim line are more in favor of blows, while fractures in the hat brim line zone are more difficult to distinguish. The majority of fractures were located on the left side for homicidal blows and on the right side for falls. A higher average number of lacerations was revealed for homicidal blows. In conclusion, this study establishes three criteria in favor of blows: (i) localization of a wound above the hat brim line; (ii) left side lateralization; and (iii) a high number of lacerations.     

Unusual blunt force wound produced by a gun muzzle

Most blunt force injuries produced by guns are associated with gun butts, and patterned, muzzle/sight impressions are usually produced by discharging firearms. An unusual and distinct forehead laceration produced by a blow with the muzzle end of a .32 caliber revolver is presented.     

The specificity of healing of fractures in the skull base

On the basis of actual observations we elucidated the main processes occurring in the reparation of fractures in the skull base. The specificity of reparation was shown to be conditioned by the structure of base bones and of surrounding tissues as well as by the nature of blood supply to them. Criteria are suggested for the determination if the lesions were inflicted in life time and when.     

Taphonomic changes to blunt force trauma: a preliminary study

This study examines the effects of taphonomic processes on blunt force trauma (BFT) through an experimental study involving pig heads. Of particular concern is the possibility that taphonomic changes can create pseudo-trauma and/or conceal evidence of actual trauma. BFT was inflicted on 10 pig skulls using a hammer. The skulls were subsequently exposed to the environment for 12 months. Seven taphonomic changes were evaluated: the freeze-thaw cycle; rodent gnawing; carnivore scavenging; presence/weight of soil; presence/weight of rain and snow; movement/displacement of bones; and discoloration due to sun bleaching and grass staining. Taphonomic effects varied between cancellous, compact, fresh, and degreased bone. Freezing and thawing, exposure to rain and snow, movement of the skulls, and soil erosion altered and, in some cases disguised, pre-existing trauma. Rodent and carnivore activity did not obliterate evidence of BFT. Recommendations for evaluating BFT on remains affected by taphonomic processes are presented. As each taphonomic process outlined by this study has the potential to disguise antemortem injury, the authors propose that one must carefully examine large, circular openings in the skull that may represent the remnant evidence of BFT.     

Unsuspected meningoencephalitis in a case of assault by blunt force trauma

Reported is a case of an assault causing extensive blunt force injuries in which the clinical, radiologic, and postmortem findings were all consistent with death resulting from brain damage arising from the assault. The assailant was charged with murder. Subsequent full neuropathologic (including histologic) examination revealed the unsuspected finding of a widespread meningoencephalitis but no evidence of significant traumatic brain damage. The contributions of the infective process and of the trauma to death were felt to be unclear and a guilty plea to attempted murder was accepted. This case highlights the importance of a full neuropathologic examination, including histology, in cases of trauma to the head, even when the cause of death may initially appear obvious.