Diffuse Axonal and Vascular Pathology in the Gyrencephalic Brain after High-Energy Blunt Injury: Clinicopathological Correlations Involving the Brainstem.

Traumatic brain injury (TBI) after high-energy, behind helmet blunt trauma (BHBT) is an important but poorly understood clinical entity often associated with apnea and death in humans. In this study, we use a swine model of high-energy BHBT to characterize key neuropathologies and their association with acute respiratory decompensation. Animals with either stable or critical vital signs were euthanized within 4 h after injury for neuropathological assessment, with emphasis on axonal and vascular pathologies in the brainstem.

Assessment of a Perfusion and Ventilation Method for Detecting Lung and Liver Injury in a Cadaveric Model.

Surgical simulation models have been developed using post-mortem human subjects (PMHS). These models involve the pressurization and ventilation of the PMHS to create a more realistic environment for training and the practice of surgical procedures. The overall objective of this study was to determine the feasibility of a previously developed surgical simulation model to detect soft tissue injuries during a ballistic impact to the torso.

Multiscale response of the human skull to quasi-static compression.

Full thickness skull specimens were extracted from the human crania, with both the inner and outer surfaces intact. The BVF-morphology (bone volume fraction) of these specimens had been previously characterized in detail and reported, with high-resolution micro-computed tomography at ~5 μm resolution. A subset of these specimens was loaded in the direction normal to the outer surface in quasi-static compression.

Structural analysis of the frontal and parietal bones of the human skull.

Bone specimens were collected from the frontal and parietal bones of 4 adult, human skulls. The microstructure was characterized using microcomputed tomography (micro-CT) at about 6-μm resolution to map the change of porosity as a function of the depth, P(d), from the inner surface nearest to the brain to the outer surface nearest to the skin. A quantifiable method was developed using the measured P(d) to objectively distinguish between the three layers of the skull: the outer table, diploë , and inner table.

Injuries of the head from backface deformation of ballistic protective helmets under ballistic impact.

Modern ballistic helmets defeat penetrating bullets by energy transfer from the projectile to the helmet, producing helmet deformation. This deformation may cause severe injuries without completely perforating the helmet, termed "behind armor blunt trauma" (BABT). As helmets become lighter, the likelihood of larger helmet backface deformation under ballistic impact increases.

Brain injury risk from primary blast.

Background: Military service members are often exposed to at least one explosive event, and many blast-exposed veterans present with symptoms of traumatic brain injury. However, there is little information on the intensity and duration of blast necessary to cause brain injury.

Methods: Varying intensity shock tube blasts were focused on the head of anesthetized ferrets, whose thorax and abdomen were protected.

Primary blast survival and injury risk assessment for repeated blast exposures.

Background: The widespread use of explosives by modern insurgents and terrorists has increased the potential frequency of blast exposure in soldiers and civilians. This growing threat highlights the importance of understanding and evaluating blast injury risk and the increase of injury risk from exposure to repeated blast effects.

Methods: Data from more than 3,250 large animal experiments were collected from studies focusing on the effects of blast exposure.

Survival risk assessment for primary blast exposures to the head.

Many soldiers returning from the current conflicts in Iraq and Afghanistan have had at least one exposure to an explosive event and a significant number have symptoms consistent with traumatic brain injury. Although blast injury risk functions have been determined and validated for pulmonary injury, there is little information on the blast levels necessary to cause blast brain injury. Anesthetized male New Zealand White rabbits were exposed to varying levels of shock tube blast exposure focused on the head, while their thoraces were protected.

Pulmonary injury risk assessment for long-duration blasts: a meta-analysis.

Background: Long-duration blasts are an increasing threat with the expanded use of thermobaric and other novel explosives. Other potential long-duration threats include large explosions from improvised explosive devices, weapons caches, and other explosives including nuclear explosives. However, there are very few long-duration pulmonary blast injury assessments, and use of short-duration exposure injury metrics is inappropriate as the injury mechanism for long-duration exposures is likely different from that of short-duration exposures.

Drosophila melanogaster larvae as a model for blast lung injury.

Background: Primary blast injuries, specifically lung injuries, resulting from blast overpressure exposures are a major source of mortality for victims of blast events. However, existing pulmonary injury criteria are inappropriate for common exposure environments. This study uses Drosophila melanogaster larvae to develop a simple phenomenological model for human pulmonary injury from primary blast exposure.

Pulmonary injury risk assessment for short-duration blasts.

Background: Blast injuries are becoming more common in modern war and terrorist action. This increasing threat underscores the importance of understanding and evaluating blast effects.

Methods: For this study, data on more than 2,550 large animal experiments were collected from more than 50 experimental studies on blast.

Thoracic and lumbar spinal impact tolerance.

Introduction: Thoracolumbar injuries resulting from motor vehicle accidents, falls, and assaults have a high risk of morbidity and mortality. However, there are no biomechanically based standards that address this problem.

Methods: This study used four cadaveric porcine specimens as a model for direct spinal impact injuries to humans to determine an appropriate injury tolerance value.

The temperature-dependent viscoelasticity of porcine lumbar spine ligaments.

Study Design: A uniaxial tensile loading study of 13 lumbar porcine ligaments under varying environmental temperature conditions.

Objectives: To investigate a possible temperature dependence of the material behavior of porcine lumbar anterior longitudinal ligaments.

Summary Of Background Data: Temperature dependence of the mechanical material properties of ligament has not been conclusively established.

A methodology for assessing blast protection in explosive ordnance disposal bomb suits.

To reduce human casualties associated with explosive ordnance disposal, a wide range of protective wear has been designed to shield against the blast effects of improvised explosive devices and munitions. In this study, 4 commercially available bomb suits, representing a range of materials and armor masses, were evaluated against 0.227 and 0.