High-velocity Bullets Research Articles

Flash X-Ray Observations of Cavitation in Cadaver Thighs Caused by High-Velocity Bullets

The purpose of this study was to record flash x-ray images of cavitation in human cadaver thighs caused by the passage of high-velocity bullets. The images are an initial step for understanding the cavitation process in human tissue and for implementing a better definition of extensive tissue injury. Bullets were fired through the mid-thighs of 13 cadaver legs. The bullets were of two calibers, 7.62-mm full metal jacket boat tail with strike velocities in the range of 794 m/s to 880 m/s (10 thighs) and 5.70 mm full metal jacket with velocities in the range of 973 m/s to 992 m/s (3 thighs). Short duration (35 ns) x-ray images were recorded at various selected times after the bullets passed near the femurs. This study was carried out at the Armed Forces Institute of Pathology under approved human subject protocols. The cavity sizes and shapes were observed for the two types of bullets and at a number of times during the expansion and collapse of the cavities. As the bullets passed through the thighs, narrow cavities behind the bullets were observed. At later times, large expanded cavities were observed that encompassed the entire mid-thigh region. The observed cavities are at variance with those which were reported previously in gelatin tissue simulants. Flash x-ray radiography is an effective technique for the observation of internal cavitation in cadaver thighs caused by high-velocity bullets. These observations suggest that gelatin is not a proven simulant for human cadaver tissue in the study of cavitation subsequent to high-velocity missile impact.

Complete Paraplegia Following Gunshot Injury Without Direct Trauma to the Cord

A retrospective review of all patients with neurologic deficit following gunshot wounds that did not penetrate the spinal canal. To evaluate the possibility that neurologic deficit following gunshot wounds is possible without direct trauma to the cord. Gunshot injuries to the spine account for 13% to 17% of all spinal cord injuries and are likely to result in complete paraplegia. Neurologic deficit is the result of direct trauma to the nervous tissue by the bullet, bone, or disc fragments, which compress the cord. The medical charts, radiographs, CT scans, and myelographies or MRIs of all patients admitted to our hospital with neurologic deficit secondary to gunshot wounds between 1977 and 2003 were reviewed. Twenty-six patients were identified: 15 with complete and 11 with incomplete paraplegia. In 19 patients, the spinal canal at the level of injury was explored and decompressed. In 3 patients with complete paraplegia at the thoracic level, CT scan, myelography (1 patient), MRI (2 patients), and operative exploration (2 patients) did not indicate any signs of canal compromise. Two were injured by low-velocity bullets passing through the vertebra (in 1 patient) and the posterior part of the lamina (in the second). The third was injured by high-velocity bullets with no signs on MRI of any injury to the vertebral column or spinal cord. At follow-up 4.1 years later, on average, none had any neurologic recovery. Neurologic deficit following gunshot wounds is possible even without violation of the spinal canal. It is most probably the result of the kinetic energy emitted by the bullet.

The Magazine: A Major Cause of Bullet Fragmentation

The fragmentation impact of high-velocity bullets penetrating the body after piercing through the magazines carried by soldiers was investigated experimentally. In this study, 16 pigs and 7.62x51-mm full metal jacket bullets were used. Pigs were assigned into two groups, and within 5 minutes of their being sacrificed with overdose anesthesia, bullets were fired into the first group on which magazines were placed and into the second group on which magazines were not placed, targeting abdominal left lower quadrant. It was found that in pigs not carrying magazines, all bullets pierced through the pig; bullets were not fragmented. However, in pigs with magazines, common fragmentation in bullets and multiple organ perforations occurred. It was concluded that magazines caused the bullets to be fragmented, increasing tissue and organ damage.

Reflections on military medicine

Reflections on military medicine

Sympathectomy for Causalgia: Experience with Military Injuries

Causalgia is a rare disease in civilian practice, and most reports regarding causalgia in the literature are from major extended wars. To increase awareness of this syndrome, our wartime experience with this disease is presented. The charts of patients with causalgia referred to two university hospitals for treatment from 1985 to 1989 were retrospectively studied. Characteristics of the cause, clinical manifestations, and the response to therapy were evaluated. Among 1,564 patients with peripheral nerve injuries, there were 54 cases (3.4%) of causalgia. All of the patients, except five, were injured in battle by high-velocity bullets or missiles. Upper extremities were involved in 28 patients (52 %) and lower extremities in 26 patients (48%). The most common presenting symptoms were as follows: burning pain, 100%; wet extremity, 100%; cold extremity, 93%; sensitivity to cold, 89%; paresthesia, 78%; and color changes in the extremities, 55%. In 48 patients (89%), pain was relieved by sympathetic block (3 patients had permanent cure). Six patients had no response to the blocks (11%). Of 45 patients who had temporary relief, all underwent sympathectomy. All of these patients had complete relief of symptoms in the immediate postoperative period and for follow-up from 1 to 6 years. Causalgia is essentially a war casualty disease. The condition is associated with burning pain, hyperesthesia, and symptoms of sympathetic overactivity. Sympathectomy is effective and the treatment of choice, particularly for patients who respond temporarily to sympathetic blocks.

The use of active speed warning signs

The problem of drivers failing to obey speed limits, even when non-compliance is dangerous, continues to present a major challenge to highway engineers. In Germany, as in the UK, attempts are being made to change drivers’ behaviour by both enforcement and persuasion. One method of persuasion being tried is the use of 'secret’ signs to warn of excessive speed. These signs are normally blank but display a warning when triggered by a speeding vehicle. The historic use of secret signs and trials of systems is presented along with a review of their use in other countries. The systems reviewed range from those which check vehicle speed to ones which check not only the speed of the vehicle but also its weight and dimensions, so that warnings specific to that vehicle can be given. A UK trial using number-plate recognition is also reviewed. Before-and-after studies have shown that in the right location these signs achieve up to 87·6% improvement in compliance with speed limits. Not all signs proved to be successful, however. The signs have been found to be most successful during their early life. As drivers become used to the signs, the effectiveness reduces. A system used in the Netherlands uses a variety of messages to overcome this problem. Vandalism has also been reported as a problem with these signs, with one in the US being destroyed by high-velocity bullets. Studies in the UK have shown that these signs can be more effective in reducing vehicle speeds than direct police enforcement using speed ‘guns’.

THE USE OF ACTIVE SPEED WARNING SIGNS.

The problem of drivers failing to obey speed limits, even when non-compliance is dangerous, continues to present a major challenge to highway engineers. In Germany, as in the UK, attempts are being made to change drivers’ behaviour by both enforcement and persuasion. One method of persuasion being tried is the use of 'secret’ signs to warn of excessive speed. These signs are normally blank but display a warning when triggered by a speeding vehicle. The historic use of secret signs and trials of systems is presented along with a review of their use in other countries. The systems reviewed range from those which check vehicle speed to ones which check not only the speed of the vehicle but also its weight and dimensions, so that warnings specific to that vehicle can be given. A UK trial using number-plate recognition is also reviewed. Before-and-after studies have shown that in the right location these signs achieve up to 87·6% improvement in compliance with speed limits. Not all signs proved to be successful, however. The signs have been found to be most successful during their early life. As drivers become used to the signs, the effectiveness reduces. A system used in the Netherlands uses a variety of messages to overcome this problem. Vandalism has also been reported as a problem with these signs, with one in the US being destroyed by high-velocity bullets. Studies in the UK have shown that these signs can be more effective in reducing vehicle speeds than direct police enforcement using speed ‘guns’.

Experience with renal gunshot injuries in a rural setting

Objectives. To investigate the high nephrectomy rate in patients with gunshot injury at Dicle University Medical School Research Hospital and to determine the factors that affect our nephrectomy decision. Methods. During a 4-year period, 71 patients were hospitalized for renal injuries at our hospital. Renal gunshot injuries (RGIs) were noted in 45 kidneys of 42 patients (59.1%). Twenty-five patients underwent nephrectomy (55.5%). Twenty kidneys were reconstructed (44.4%). The hospital records were reviewed retrospectively. In these two groups of patients, the following clinical data were entered into a computer data base and compared: presence and type of hematuria, type and degree of renal injury, hemodynamic status, results of imaging studies, surgical technique, type of weapon, reason for nephrectomy, associated organ injury, injury severity score, complications, and mortality. Results. The patients who underwent renal repair and those who underwent nephrectomy had a mean injury severity score of 33.6 ± 7.5 and 42.0 ± 9.9, respectively ( P <0.001). The main grade of injury was 4.4 ± 0.8 in nephrectomy patients and 2.8 ± 0.9 in the patients for whom renal salvage was possible ( P <0.05). Patients who required nephrectomy, as a group, appeared to have a higher rate of high-velocity bullet injury (HVBI) (76%) ( P <0.05) and higher numbers of associated abdominal injury ( P <0.05). Conclusions. HVBI makes extensive tissue debridement imperative and reconstruction difficult. We believe that in RGIs caused by a high-velocity bullet, nephrectomy is more likely to be required. Hemodynamic instability was the major reason for our intraoperative nephrectomy decision. HVBI should be accepted as a subcategory of RGI.

Post failure analysis of 0 degrees /90 degrees ultra high molecular weight polyethylene composite after ballistic testing

The ballistic performance of a 0 degrees /90 degrees ultra high molecular weight polyethylene (UHMWPE) composite was investigated. Two areal densities were considered: one for fragmentation protection and one for high velocity bullet protection. The role of microscopy in the post-failure analysis of the UHMWPE was explored. Stereo, optical and environmental scanning electron microscopy were utilized and attempts were made to correlate the results obtained with other characterization techniques available. These included high speed photography, visual inspection and ultrasonic inspection. Visual inspection revealed the gross effects of ballistic testing. These primarily included deformation and delamination of the composite plate. The result obtained corresponded with the predicted impact event and, for high velocity bullet impact, corresponded well to the images obtained using high speed photography. Optical, stereo and electron microscopy allowed for fibre and matrix characterization. Fibre displacement and pull-out were also observed on impact and exit faces.

Defect fractures of the upper arm and their treatment in difficult circumstances. 3 case reports from Ethiopian and Somalian provincial hospitals

Gunshot fractures of the extremities often result in large bone defects and disability. The reconstruction of the bone is the essential precondition for a successful rehabilitation. This is a report on three patients who suffered from substantial bone defects of the humerus shaft caused by high-velocity bullets. In one patient the injury happened 3 days before admission, in another patient 5 months before. The third patient had a history of 11 years since the injury with numerous operations, bone grafts included. He presented with an infected non-union. All three patients had a complete radial nerve paralysis right from the beginning, as they have reported. Debridement, sequestrectomy and immobilisation by an external fixator with a device for compression and distraction were the first steps in management, followed by slow compression and, after a free interval, by distraction for 1 mm per day over a period of ca. 4 weeks. After distraction, one patient had early spontaneous callus formation. Two patients received a spongious bone graft, and in one of them decompression of the radial nerve was carried out during the operation for bone grafting. Subsequently, all three patients showed good callus formation. When strong ossification was visible on the X-rays, the fixator was removed and a PoP brace applied. The change from the external fixator to an internal fixation by a plate was not necessary and, under the prevailing conditions, not even possible. The patients were discharged with the brace and encouraged to continue with exercises. When the patients came back for a follow-up examination, the fracture sites were stable and the bones showed good consolidation. In two cases, the function of the radial nerve was nearly completely restored, in the patient with the long history, of course, there was no change. All three patients were free of infection. These three cases show that, even under the unfavourable conditions of civil war and in hospitals of less prosperous countries, the treatment of large bone defects can be successful, provided material and sometimes personnel support is, if necessary, given to the hospitals dealing with war and accident victims.

The Molecular Outflow and CO Bullets in HH111

We present high angular resolution observations of the molecular outflow associated with the optical jet and HH objects of the HH111 system. Interferometric observations in the CO J =2–1 and J =1–0 lines of the high velocity bullets associated with HH111 are presented for the first time. The molecular gas in these high velocity clumps has a moderate kinetic temperature and a mass of a few 10–4 M⊙ per bullet. We favor the view that HH jets and CO bullets, which represent different manifestations of the same physical phenomena, are driving the low-velocity molecular outflow.

New technology in wound ballistics: the Doppler radar.

The feasibility of using Doppler radar to obtain more accurate measurements of velocity and yaw angle of bullets was investigated. Anesthetized pigs were shot at a range of 9-10 meters, and velocity measurements were obtained using Doppler radar and photocells. The data from the two types of equipment was compared. Excellent correspondence was found between the measurements of entry velocities of low, medium, and high velocity bullets, i.e., an average deviation of less than 1% (range 0-2%). Measurements of exit velocities of low and medium velocity bullets corresponded just as well, but measurements of exit velocities of high velocity bullets was complicated in both methods by signal cluttering caused by fragments of tissue released from the exit wound and by the deflection of the bullet. A Doppler radar was used to follow the movements of the bullet, to determine the velocity, and, if possible, to determine when the bullet stabilizes and the exact yaw angles continuously. We were able to design a system in which even small caliber bullets could be followed for 15-20 meters. It was possible to detect yaw even with these small calibers, and the radar was not disturbed by additional equipment. Using Doppler radar to measure velocity offers important benefits--simple set up, minimal risk of damage to equipment by stray bullets, and very good accuracy. The results of measuring yaw angles of bullets are promising, as far as determining the point of stability is concerned, but further work is necessary to be able to measure the angle of yaw exactly.

Truncal gunshot wounds in Finland, 1985 to 1989.

A nationwide survey of truncal gunshot wounds identified 119 patients managed in 34 institutions. The wounds resulted from low-velocity bullets in 69%, high-velocity bullets in 6%, and shotgun pellets in 25%. The thoracic or abdominal cavity was penetrated in 62%, and the mean Injury Severity Score was 16 (range, 1 to 57). The wounding capacity of close-range shotgun pellets equaled that of high-velocity bullets, whereas long-range (>10 meters) shotgun injuries resembled air rifle injuries in their poor ability to penetrate deeper structures and cause internal injuries. A thoracotomy or sternotomy was required in 31% of the penetrating thoracic injuries. Of 57 laparotomies, 9% were negative. In four cases (7% of all laparotomies), a significant abdominal organ injury was overlooked at the initial operation, emphasizing the importance of meticulous exploration of all abdominal organs, and especially the diaphragm and the retroperitoneal structures.

High-Velocity Bullet Causing Indirect Trauma to the Brain and Symptomatic Epilepsy

Epilepsy is a frequent consequence after missile wounds of the brain. So far, no epilepsy cases with missile injury have been described in which epilepsy ensued without direct missile injury of the brain. During World War II, in 1941, our patient, then a soldier in the German army, suffered a bullet injury to the head; the bullet entered the cranium at the base of the nose. The bullet penetrated the head below the base of the cranium and remained stuck subcutaneously left of the second cervical vertebra. In the field hospital the patient suffered from focal seizures. The fits ceased within a few years under medication. In 1990 the seizures returned, this time with secondary generalization. In our case, a 7.62-mm bullet from the Russian Tokarev military pistol was used, which is known to have the highest muzzle velocity of all handguns available (> 500 m per second). We suspect that the so-called hydrodynamic effect of this high-velocity bullet caused an indirect trauma to the brain. This case shows that symptomatic epilepsy can occur after a penetrating head injury, without direct injury to brain tissue by a missile. High-velocity missiles are increasingly used in armed conflicts around the world. In light of the case reported here, in which the initial epilepsy was exacerbated more than 50 years after the wounding event, physicians must consider this possibility when dealing with veterans presenting with seizures. This case also has implications for the payment of benefits and pensions.

Canadian attitudes toward use of primary repair in management of colon trauma

The majority of recent American articles on management of colon trauma promote liberal use of primary repair. The extent to which Canadian surgeons have embraced such recommendations is unknown. To determine the current attitude of Canadian surgeons toward the use of primary repair, we surveyed the members of The Canadian Association of General Surgeons regarding their management of three fictitious cases of penetrating and blunt colon trauma. Three hundred seventeen members of the Canadian Association of General Surgeons responded. Ninety-two percent managed a fictitious case of early, uncontaminated stab wounds by primary repair. Delay in treatment or fecal contamination was associated with a significantly reduced number of respondents choosing primary repair (P < 0.001). Surgeons were less likely to choose primary repair for management of a case of blunt colon injury (35 percent; P <0.001), and only 25 percent considered primary repair an option for a case of low velocity bullet wounds; 2 percent chose it for high velocity bullet wounds. Overall, the most common response to colon trauma scenarios was colostomy. However, 96 percent of respondents selected primary repair as the treatment of choice for at least one clinical situation depicted in the questionnaire. The likelihood of choosing primary repair was independent of surgeons' experiences or the level of the surgeons' trauma center. Although there are still settings in which many Canadian surgeons consider colostomy the appropriate treatment for colon injuries, primary repair has definitely established a foothold in all levels of Canadian general surgery practice.

Gut-derived endotoxemia and multiple system organ failure following gunshot wounds combined with hemorrhagic shock: an experimental study in the dog.

The purpose of this study was to explore the causative effects of high-velocity bullet injury (5.56 mm, 930 m/sec) combined with hemorrhagic shock on gut-derived endotoxemia and multiple system organ dysfunction or failure. The concentration of endotoxin in both portal and systemic blood was markedly increased after gunshot wounds together with hemorrhagic shock (p < 0.05-0.01). The portal/systemic lipopolysaccharide ratio persistently decreased in the combined wound (CW) group at 24 to 72 hours after injury, and it was much lower in the CW group than that in the single gunshot wound (SW) group. Also, a significant increase of fecal endotoxin content was found in the CW group as compared to the SW group (118.30 +/- 75.36 vs. 8.89 +/- 3.32 micrograms/g, p < 0.01), which was paralleled with the population of gram-negative bacilli in the intestinal tract. The incidence of multiple system organ failure, multiorgan dysfunction (including single organ failure) in the CW group were 30.8% (4 of 13) and 38.5% (5 of 13), respectively. These results suggested that severe trauma could lead to gut origin endotoxemia and bacterial translocation, which might play an important role in the pathogenesis of sepsis and multiple system organ failure following gunshot wounds.

The initial yaw of some commonly encountered military rifle bullets.

The yaw angle in flight of high velocity bullets has been discussed for a number of years, due to its contribution to the tumbling of the bullet in the target. Since few unclassified reports of contemporary bullets are available, we investigated the yaw angles of the bullets used in the M16A2, G3, AK-47 and AK-74 rifles by the shadowgraph technique. Our results show that bullets from military rifles tend to stabilize at less than 3 degrees within 25 m, and this angle has been thought to be insignificant in the production of gunshot wounds. Bullets from some modern small calibre high velocity rifles such as the M16A2 and the AK-74 can have quite large yaw angles in their initial flight. The results, which confirm the opinion of contemporary writers, should settle the controversy in this area of wound ballistics.

High-velocity gunshot wound through bone with low energy transfer

It is recognized that high-velocity missile wounds may only produce a low energy transfer wound, but that high-velocity wounds involving bone invariably lead to high energy transfer, with consequent shattering of the bone. A case is presented where a high-velocity bullet passed through a long bone with low energy transfer, and where additionally the wound track was not visible on a plain radiograph. This has not been previously described. The pathophysiology and management of high-velocity gunshot wounds is briefly discussed; emphasis is given to adequate surgical treatment and wound closure by delayed primary suture.

Traumatic spinal cord injuries in Turkey.

Spinal cord lesions have various aetiologies, and trauma is one of the leading causes. Patients with spinal cord injuries (SCI) often have motor, sensory and autonomic dysfunctions and require a multidisciplinary rehabilitation programme. In this study 1694 SCI patients were investigated, including the frequency, and the distribution by age, sex, profession, aetiology, clinical status and year of occurrence. Traumatic SCI is more frequent among males than females and among those between the ages of 15 and 39 years. Regarding the aetiology, traffic accident comprised 35.41% of the total cases, the second most common cause was falls with 29.51%, and the third was high velocity bullet wounds: 21.95%.

Simple analogies in general chemistry

Great Plains Indians and Dalton's Law; bullets, BB's, and the photoelectric effect; and high velocity bullets and high frequency light.