The effect of military clothing on gunshot wounding patterns in gelatine

Experimental model and simulant for studying blast penetrating injury to the skin

Energised fragments from explosions are the most common wounding mechanism in conflicts and terrorist attacks. Skin covers the vast majority of the human body and is therefore the first anatomical component to be penetrated by fragments, however, its resistance to penetration largely has not been taken into account in models of injury. In this study, an experimental model for ballistic testing of skin is established and a suitable skin simulant for studying resistance to penetration is determined. Fragment-simulating projectiles were fired at human cadaveric skin and skin-simulant candidates. Tissue responses were quantified by evaluating the impact velocity at 50% risk of skin penetration and perforation, and the depth of penetration in cadaveric tissue or skin-simulant candidates. The results identified a 1.5-mm-thick butyl rubber as a suitable skin simulant across the range of threats tested. The findings can help refine assessment of protective systems and predictive models of injury in an effort to improve outcomes of fragment-penetrating injuries.

The use of human tissue surrogates in anatomical modeling for gunshot wounds simulations: an overview about "how to do" experimental terminal ballistics

Human tissue simulating materials are currently used in scientific research mainly because they help to avoid possible ethical issues, unlike what happens with studies involving live animals and/or human cadavers. The use of ballistic gelatin as a human soft tissue surrogate stands out, although other types of materials can be used, including polyurethane and polydimethylsiloxane in the simulation of bones and skin respectively, not to mention some computational models that completely replace the physical use of surrogate models for gunshot wound simulation. The use of human tissue surrogates can be useful in reconstructing the dynamics of a crime scene when important forensic traces cannot be found. In the absence of projectiles but in possession of the possible firearm used in the crime, for example, it is possible to verify whether the weapon in question actually fired the fatal gunshot by comparing the injury found on the victim with the injury produced on the simulant material that best represents the anatomical area impacted, as indicated in the literature. Thus, scientific advances in experimental research in terminal ballistics with tissue surrogates can positively impact applied forensic sciences in the search for better technical assistance to the justice system in solving criminal situations.

Assault rifle injuries in civilians: ballistics of wound patterns, assessment and initial management

PURPOSE

Wounds from assault rifles and their commercial offspring have been encountered with increasing frequency in civilian practice. Our aim is to summarize wound ballistics related to the main injury patterns that can also affect management strategies.

METHODS

An online search of the PubMed was conducted for research and review articles published after 2000 in English, using the MeSH terms "gunshot wounds", "mass casualty incidents", "war-related injuries", "soft tissue injuries", "vascular system injuries", "colon injuries", "wound infection", "antibiotic prophylaxis", "debridement", "hemorrhage", "penetrating head injuries", "pneumothorax" and additional free-text terms. Other academic databases were also searched for relevant articles and book chapters.

RESULTS

Consensus regarding recognition of high energy wounds from assault rifle projectiles is largely based on war experience. Studies of such wounds inflicted by expanding projectiles suggest that their wounding effects significantly increase tissue damage and adverse outcomes following injury, as a result of the temporary cavity and bullet fragmentation. The use of assault rifles in mass shootings has prompted utilization of tourniquet for control of life-threatening hemorrhage, also derived from military experience, while limited evidence indicates that tension pneumothorax rather than extremity wounds is the leading cause of potentially preventable death in these incidents.

CONCLUSIONS

Wound ballistics provides a system for evaluation of injuries from assault rifles and risk analysis of shooting incidents. Lessons learned from armed conflicts can improve the management of victims, with due consideration given to characteristics of civilian injuries. Further research is required to define the impact on survival by key life-saving procedures in the prehospital setting, in order to prioritize these interventions.

Experimental Tests on External and Terminal Ballistics of Different Types of Projectiles Fired From .38 SPL Caliber Cartridges and Study of Permanent Cavitation in Anatomical Modeling With 10% Ballistic Gelatin

ABSTRACT

The present study investigated the main morphological differences between the permanent cavities formed by 4 different types of projectiles fired from .38 SPL caliber cartridges in blocks of 10% ballistic gelatin with standardized formulation (Federal Bureau of Investigation Protocol), all fired from the same distance and from the same firearm, associated with its performances in external and terminal ballistics. The velocity or the mass presented by a firearm projectile will not always be solely responsible for the final configuration of the permanent cavity, in which the projectile design, for example, is an equally important element. Each type of projectile tested in the present work generated a different kind of permanent cavity, but they also varied in velocity (m/s) and energy (J). The use of 10% ballistic gelatin in scientific research that seeks to investigate the external and terminal ballistics of projectiles can contribute to the practice of professionals working either in forensic pathology or applied ballistics scenarios, as they can experimentally simulate the events that can occur in the tissues of victims inflicted by gunshot wounds, which also allows important applications in the medical, commercial, civil, and military sectors that deal with products and technologies related to the human body.

Ballistic research techniques: visualizing gunshot wounding patterns

There are difficulties associated with mapping gunshot wound (GSW) patterns within opaque models. Depending on the damage measurement parameters required, there are multiple techniques that can provide methods of "seeing" the GSW pattern within an opaque model. The aim of this paper was to test several of these techniques within a cadaveric animal limb model to determine the most effective. The techniques of interest were flash X-ray, ultrasound, physical dissection, and computed-tomography (CT). Fallow deer hind limbs were chosen for the model with four limbs used for each technique tested. Quarantined 7.62 × 39 mm ammunition was used for each shot, and each limb was only shot once, on an outdoor range with shots impacting at muzzle velocity. Flash X-ray provided evidence of yaw within the limb during the projectile's flight; ultrasound though able to visualise the GSW track, was too subjective and was abandoned; dissection proved too unreliable due to the tissue being cadaveric so also too subjective; and lastly, CT with contrast provided excellent imaging in multiple viewing planes and 3D image reconstruction; this allowed versatile measurement of the GSW pattern to collect dimensions of damage as required. Of the different techniques examined in this study, CT with contrast proved the most effective to allow precise GSW pattern analysis within a cadaveric animal limb model. These findings may be beneficial to others wishing to undertake further ballistic study both within clinical and forensic fields.

Preliminary effect of projectile yaw on extremity gunshot wounding in a cadaveric animal model: a serendipitous study

Gunshot wounding (GSW) is capable of causing devastating tissue injuries by delivering kinetic energy (KE) through the contact surface area of a projectile. The contact surface area can be increased by yaw, deformation and fragmentation, all of which may be caused by any intermediate layers struck by the projectile prior to entering its target. This study aims to describe whether projectile yaw occurring before penetration of a cadaveric animal limb model causes greater damage with or without clothing layers present using 5.45 × 39 mm projectiles. In total, 12 fallow deer hind limbs were shot, further divided into 4 with no clothing layers (Cnil), 4 with a single clothing layer (Cmin) and 4 with maximum clothing layers (Cmax) as worn on active duty by UK military personnel. Contrast computed tomography (CT) of limbs was used to measure permanent cavity size and the results were compared using analysis of variance (ANOVA). No significant differences were found among clothing states for each series of measurements taken, with greater cavity sizes noted in all clothing states. This is in contrast to previous work looking at symmetrically flying projectiles in the same model, where a larger permanent cavity was found only with Cmax present. Projectile yaw is therefore likely to be a key variable with regard to causation of damage within this extremity wound model.

The effect of military clothing on gunshot wound patterns in a cadaveric animal limb model

The majority of injuries in survivors of gunshot wounds (GSW) are typically to the extremities. Novel wound ballistic research is encouraged to try and capture corporate knowledge on the management of these injuries gained during recent conflicts and understand the wounding patterns seen. With recent work examining the effect of UK military clothing on extremity GSW patterns in a synthetic model, a model with greater biofidelity is needed for ballistic testing. The aim of this study was to assess the effect of UK military clothing on GSW patterns within a cadaveric animal limb model using two types of ammunition commonly used in recent conflicts—7.62 × 39 mm and 5.45 × 39 mm. In total, 24 fallow deer hind limbs were shot, 12 by 7.62 mm projectiles and the remaining 12 shot by 5.45 mm projectiles, further divided into four with no clothing layers (C_nil), four with a single clothing layer (C_min) and four with maximum clothing layers (C_max) as worn on active duty by UK military personnel. Limbs were analysed after ballistic impact using contrast CT scanning to obtain measurements of permanent cavity damage, and results were compared using analysis of variance (ANOVA). Results showed significantly different damage measurements within limbs with C_max for both ammunition types compared with the other clothing states. This may result in GSWs that require more extensive surgical management, and invites further study.

Effects of police body armour on overmatching ballistic injury

Overmatching occurs when body armour that has been designed to resist perforation by a specified projectile is perforated by a greater threat. This may result in wounding to the body armour wearer. In this work, overmatching of two types of police body armour was studied using two types of ammunition. The use of a 250-mm-long gelatine block to represent the depth of the human torso combined with armour panels mounted on the anterior and posterior of the block allowed for a more realistic simulation to be completed. There was some evidence to suggest that overmatching events could lead to increased levels of damage during a survivable incident compared with no body armour being present. This information is of interest to armour designers and medical personnel that might treat such wounds.