Primary blast wave protection in combat helmet design: A historical comparison between present day and World War I.

Since World War I, helmets have been used to protect the head in warfare, designed primarily for protection against artillery shrapnel. More recently, helmet requirements have included ballistic and blunt trauma protection, but neurotrauma from primary blast has never been a key concern in helmet design. Only in recent years has the threat of direct blast wave impingement on the head-separate from penetrating trauma-been appreciated. This study compares the blast protective effect of historical (World War I) and current combat helmets, against each other and 'no helmet' or bare head, for realistic shock wave impingement on the helmet crown. Helmets included World War I variants from the United Kingdom/United States (Brodie), France (Adrian), Germany (Stahlhelm), and a current United States combat variant (Advanced Combat Helmet). Helmets were mounted on a dummy head and neck and aligned along the crown of the head with a cylindrical shock tube to simulate an overhead blast. Primary blast waves of different magnitudes were generated based on estimated blast conditions from historical shells. Peak reflected overpressure at the open end of the blast tube was compared to peak overpressure measured at several head locations. All helmets provided significant pressure attenuation compared to the no helmet case. The modern variant did not provide more pressure attenuation than the historical helmets, and some historical helmets performed better at certain measurement locations. The study demonstrates that both historical and current helmets have some primary blast protective capabilities, and that simple design features may improve these capabilities for future helmet systems.

Prototype screwdriver stopper to avoid intracranial penetration injury.

Screwdriver slipping from the tapping screw head (screwdriver slip) represents a very dangerous situation that leads to the risk of entry into the intracranial operation field. We have developed a screwdriver stopper device to attach to the top of the screwdriver in order to prevent intracranial penetration injuries. We performed 48 craniotomies in our institute. The instrument is made from clear acrylic with a central hole (diameter, 3 mm). We checked the number of screwdriver slip events, as a precursor to intracranial penetration injury, in screwdrivers from five different companies, and compared the results. We used 496 tapping screws in 512 tightening procedures. Although screwdriver slip occurred at an overall rate of 17/512(3.3%), we completely avoided serious intracranial penetration injuries. No significant differences in rates of screwdriver slip were seen between the five companies (χ2 test, p = 0.997). Screwdriver slip is a precursor to intracranial penetration injury, but cannot be avoided with cross-type screwdrivers. Many neurosurgeons may be operating without knowledge of the potential risk of intracranial penetration injury. The screwdriver stopper described herein may prove extremely useful for preventing intracranial penetration injuries during neurological surgery.

Nail gun injuries to the head with minimal neurological consequences: a case series.

BACKGROUND: An estimated 3700 individuals are seen annually in US emergency departments for nail gun-related injuries. Approximately 45 cases have been reported in the literature concerning nail gun injuries penetrating the cranium. These cases pose a challenge for the neurosurgeon because of the uniqueness of each case, the dynamics of high pressure nail gun injuries, and the surgical planning to remove the foreign body without further vascular injury or uncontrolled intracranial hemorrhage. CASE PRESENTATION: Here we present four cases of penetrating nail gun injuries with variable presentations. Case 1 is of a 33-year-old white man who sustained 10 nail gunshot injuries to his head. Case 2 is of a 51-year-old white man who sustained bi-temporal nail gun injuries to his head. Cases 3 and 4 are of two white men aged 22 years and 49 years with a single nail gun injury to the head. In the context of these individual cases and a review of similar cases in the literature we present surgical approaches and considerations in the management of nail gun injuries to the cranium. Case 1 presented with cranial nerve deficits, Case 2 required intubation for low Glasgow Coma Scale, while Cases 3 and 4 were neurologically intact on presentation. Three patients underwent angiography for assessment of vascular injury and all patients underwent surgical removal of foreign objects using a vice-grip. No neurological deficits were found in these patients on follow-up. CONCLUSIONS: Nail gun injuries can present with variable clinical status; mortality and morbidity is low for surgically managed isolated nail gun-related injuries to the head. The current case series describes the surgical use of a vice-grip for a good grip of the nail head and controlled extraction, and these patients appear to have a good postoperative prognosis with minimal neurological deficits postoperatively and on follow-up.

Defining combat helmet coverage for protection against explosively propelled fragments.

INTRODUCTION: Prevention against head wounds from explosively propelled fragments is currently the Mark 7 general service combat helmet, although only limited evidence exists to define the coverage required for the helmet to adequately protect against such a threat. The Royal Centre for Defence Medicine was tasked by Defence Equipment and Support to provide a framework for determining the optimum coverage of future combat helmets in order to inform the VIRTUS procurement programme. METHOD: A systematic review of the literature was undertaken to identify potential solutions to three components felt necessary to define the ideal helmet coverage required for protection against explosively propelled fragments. RESULTS: The brain and brainstem were identified as the structures requiring coverage by a helmet. No papers were identified that directly defined the margins of these structures to anatomical landmarks, nor how these could be related to helmet coverage. CONCLUSIONS: We recommend relating the margins of the brain to three identifiable anatomical landmarks (nasion, external auditory meatus and superior nuchal line), which can in turn be related to the coverage provided by the helmet. Early assessments using an anatomical mannequin indicate that the current helmet covers the majority of the brain and brainstem from projectiles with a horizontal trajectory but not from ones that originate from the ground. Protection from projectiles with ground-originating trajectories is reduced by helmets with increased stand-off from the skin. Future helmet coverage assessments should use a finite element numerical modelling approach with representative material properties assigned to intracranial anatomical structures to enable differences in projectile trajectory and helmet coverage to be objectively compared.

Tromboprofilaxis en el paciente politraumatizado y con traumatismo craneoencefálico / Thromboprophylaxis in multiple trauma and head injury patients

La enfermedad tromboembólica venosa (ETV) es una importante entidad clínica (epidemiológica, por su gravedad y costes), con elevada mortalidad por infradiagnóstico o tratamiento inadecuado, especialmente en pacientes como la población traumática. La incidencia de la ETV en estos pacientes varía de un 5 a 58% y se considera esencial la tromboprofilaxis para su correcto manejo. Tradicionalmente, las fracturas de pelvis y extremidad inferior, presencia de trauma craneal y la inmovilización prolongada han sido considerados factores de riesgo de ETV, sin embargo no está claro qué combinación de estos factores y otros puedan ser predictores de alto riesgo. En la actualidad, la estrategia óptima de profilaxis de la ETV para los pacientes politraumatizados es desconocida. La tromboprofilaxis se puede realizar con medidas mecánicas y con tratamientos farmacológicos. En la mayoría de estos pacientes, las principales guías recomienda la tromboprofilaxis con heparina de bajo peso molecular (HBPM) que se puede iniciar a las 48 horas y en pacientes con hemorragia activa debe ser considerada la compresión mecánica, a pesar de su eficacia limitada, hasta que el riesgo de hemorragia haya disminuido. No existen datos suficientes para justificar la realización rutinaria de ecografía o flebografía en todos estos pacientes. En el caso de los pacientes con traumatismo craneoencefálico y riesgo de hemorragia intracraneal, se recomienda retrasar el inicio de la tromboprofilaxis con HBPM hasta la desaparición de dicho riesgo pero se puede valorar la utilización de las medidas mecánicas según la situación clínica (AU)

Venous thromboembolic disease (VTD) is a frequent condition with serious clinical consequences and elevated mortality related to underdiagnosis or undertreatment, especially in patients with multiple trauma. The incidence of VTD in these patients ranges from 5% to 58% and thromboprophylaxis is considered essential for proper management. Traditionally, pelvic and lower extremity fractures, head injury, and prolonged immobilization have been cited as risk factors for VTD; however, how these factors combine with others to predict high risk is still unclear. The best way to approach VTD prophylaxis in multiple trauma patients is currently unclear. Both mechanical and pharmacologic means are available. The main clinical practice guidelines recommend thromboprophylaxis with low-molecular weight heparin, which can be started 48 hours after trauma, unless patients are still bleeding, in which case mechanical compression is recommended in spite of the limited effectiveness of that measure. Compression is maintained until the risk of hemorrhage has diminished. There is insufficient evidence to support routine use of ultrasound imaging or venography. In patients with head injury who are at risk for intracranial bleeding, the use of low-molecular weight heparin should be delayed until risk disappears but mechanical prophylaxis (compression) can be considered according to clinical status (AU)

Anatomic distribution of bullet head injuries in combat fatalities.

BACKGROUND: Gun-shot wound head injury comprises a substantial fraction of combat injuries and a major cause of death in the battlefield. Current shielding gear is totally ineffective against bullets, because bullet-proof materials are too heavy to be worn on the head. The aim of this work was to describe the anatomic distribution of bullet entry wounds to the head in combat fatalities and to discern whether distribution is random (null hypothesis) or not. METHODS: We retrospectively examined the forensic external examination reports of all Israeli Defense Forces combat fatalities during the years 2000 to 2004, the Second Lebanon War (2006), and Operation Cast Lead (2009) and mapped the exact anatomic location of all bullet entry wounds to the calvaria. RESULTS: We found 76 gun-shot entry wounds to the heads of 49 fatalities. Among these wounds, the occipital and anterior-temporal regions were found to be hit significantly more often than expected compared with their relative surface area (p < 0.001 and p < 0.001, respectively). Fifty-five percent of all injuries occurred within 15% of the surface area of skull. CONCLUSIONS: These findings imply that gun-shot entry wounds to the head are unevenly distributed. A partially bullet-proof protective helmet may prevent a substantial fraction of injuries (and fatalities) without a significant weight addition to the helmet.

Alert: the dark side of chats--internet without boundaries.

The web has some unique advantages: It eliminates barriers of space and time; information flows quicker and is more accessible to all; the markets are more effective; community and interpersonal communication is more evolved. However, the web is also anonymous, without supervision, freedom of speech is exploited, minors and other web users are exploited, racism and prejudice are encouraged. These manifestations of violence not only hurt many people but actually pose a threat to the existence of the web as a place for exchanging ideas and thoughts, as a tool for relaying messages in a liberal and democratic fashion. Today, it is not legally possible to stop any discussion group or chats, like the one in which Eran participated, which develop dialogues regarding death or suicide. A wise and proper use of the web will be achieved by agreements and not enforcement. It is a process of education in its widest meaning that will be accomplished through the acceptance of norms. Proper use of the web will be possible when all sides--users, site owners and suppliers--willingly commit to values of mutual respect, decency and protection of individual fundamental rights to freedom. The web, which is a great blessing to the communication between people, organizations and cultures, carries with it substantial risks, especially to young users. The rapid expansion of the web and the increase in the number of users has brought many social-ideological dangers alongside the many advantages. In order to deal with these issues, a few years ago I initiated an association known as Eshnav (www.eshnav.org.il) which acts to increase public awareness to the risks and dangers of the web. Eshnav's mission, established to commemorate Eran's memory, is to promote public awareness to the positive and negative aspects of using the web on society and its values, and to promote the wise and safe use of the web. Eran was in great distress and needed empathy, encouragement and support. Sadly, when his mind was filled with suicidal thoughts he stumbled upon a group on the web that embraced the culture of death and suicide discussions. In his darkest moments, when he was on the verge of an abyss, he was probably pushed by these discussions into his death, and he was only 19-years-old. When Eshnav was created we saw the dangers of an Internet with no boundaries, a place where this remarkable technology was grossly misused. This is from the association's statement: "In a world without fences and boundaries clearer rules of conduct are needed." We emphasized that "the web is like a new world that has yet to determine its own boundaries. As such, it poses new challenges, both moral and ideological, which cannot be met based on past experience as this phenomenon is still too new and uncharted. We must do the utmost to be vigil about making the Internet as safe as possible even when this new frontier is constantly shifting and evolving." Let us bow our heads in sadness in memory of Eran whose strength did not withstand the great distress he was in, and who let himself be dragged by the death culture and darkness on the web into an untimely grave. We shall find strength in our determination to create a responsible web community in which freedom of speech will not be abused to hurt the individual rights of each and every human being to life, respect, reputation and privacy.

Actuació davant el traumatisme cranioencefàlic lleu al servei d'urgències / No disponible

No disponible

Dynamic effects of a 9 mm missile on cadaveric skull protected by aramid, polyethylene or aluminum plate: an experimental study.

BACKGROUND: Most military helmets are designed to prevent penetration by small firearms using composite materials in their construction. However, the transient deformation of the composite helmet during a non penetrating impact may result in severe head injury. METHOD: Two experimental designs were undertaken to characterize the extend of injuries imparted by composite panels using in protective helmets. In the first series, 21 dry skulls were protected by polyethylene plates, with gaps between the protective plate and skull ranging from 12 to 15 mm. In another design, using 9 cadavers, heads were protected by aluminum, aramid, or polyethylene plates. Specimens were instrumented with pressure gauges to record the impact response. The ammunition used in these experiments was 9 mm caliber and had a velocity of 400 m/s. A macroscopic analysis of the specimens quantified fractures and injuries, which were then related to the measured pressures. RESULTS: Protective plates influenced both the levels of injury and the intracranial pressure. Injuries were accentuated as the plates was changed from aluminum to composite materials and ranged from skin laceration to extensive skull fractures and brain contusion. Fractures were associated with brain parenchymal pressures in excess of 560 kPa and cerebrospinal fluid pressure of 150 kPa. An air gap of a few millimeters between the plate and the head was sufficient to decrease these internal pressures by half, significantly reducing the level of injury. CONCLUSIONS: Ballistic helmets made of composite materials could be optimized to avoid extensive transient deformation and thus reduce the impact and blunt trauma to the head. However, this deformation cannot be completely removed, which is why the gap between the helmet and the head must be maintained at more than 12 mm.