PubMed Health⌕ Search

Biomedical subjects

B Karger

Publications and source records attributed to B Karger.

At least 55 records · Page 3Linked to original sources

Who fired the gun? A casuistic contribution to the differentiation between self-inflicted and non-self-inflicted gunshot wounds.

A fatal gunshot wound to the thorax from a .357 Magnum revolver is reported. The entrance wound was located dorsally at the transition of the right shoulder and the upper arm, the exit wound below the left axilla and a re-entry at the medial aspect of the left upper arm. A friend of the victim, who was present when the gunshot was fired, stated that it was a self-inflicted accident. But the inclusion of both upper arms in the trajectory allowed a comparison between the posture of the upper arms at the moment the gunshot was fired and the posture of the upper arms necessary for a self-inflicted gunshot wound. This reconstruction, which is presented in detail, definitely excluded a self-inflicted wound. The friend then confessed that he had fired the gun accidentally.

Accidents↗

Prior exposure of the entrance wound region from clothing is uncommon in firearm suicides.

According to an old rule still in use, gunshot suicides will rarely shoot through the clothing but will pull it aside to bare the skin. Thus, a bullet defect in the clothing would be an indicator for homicide or an accident. A total of 138 clearly defined gunshot suicides were analysed with regard to this topic. The thorax, which is commonly covered by textile, was the target for 27 suicides (19.5%). Of these 27 persons, 25 had fired through the clothing and 2 had placed the muzzle directly on the exposed skin, which represents a relative frequency of only 7%. Special features such as thick clothing or an affected state of mind did not appear to influence this behavior. Consequently, the perforation of textile does not suggest homicide or an accident - it is not applicable as a criterion for distinguishing different modes of death. Only in the rare cases when a gunshot victim is found with intact clothing covering the entrance wound can this finding be interpreted as an indication for suicide.

Clothing↗

Laceration of the thoracic aorta from a .22 lr bullet.

A gunshot wound (.22 long rifle) to the chest including perforation of the aorta ascendens is presented. The small wound tract in soft tissue was characteristic for this type of ammunition and did not show any special peculiarities. However, arterial injury was not restricted to two small perforations, as expected in the light of previous wound ballistic findings. Three large longitudinal ruptures (3.0-4.5 cm in length and two of them independent of the perforations) additionally occurred, which led to rapid exsanguination. This extraordinary extent of vascular injury can be explained by perforation of the artery during the ventricular ejection phase, which causes a considerable dilation of the aorta analogous to a windkessel. The pre-existing dilation enables intraluminal temporary cavitation to have an "explosive" effect despite the high elastic tolerance to the vessel wall. The importance of tissue characteristics in gunshot wounds in general and the possible role of temporary cavitation inside the vessel in vascular gunshot wound production in particular are stressed.

Adult↗

STR analysis on perforating FMJ bullets and a new VWA variant allele.

In three separate shooting incidents involving multiple gunshots, two FMJ bullets and one bullet fragment found at the scene (one from each case) were investigated for the presence of biological material from the victim after perforation. The surface of the missiles, which did not show obvious tissue traces when examined under a macroscope, was swabbed. PCR typing of up to five STR loci was performed on the small amounts of DNA extracted, which were seen below the detection limit of the slot blot quantification in one case. Nevertheless, individualisation of cellular material from the perforating projectiles was successful in each of the three cases presented. Consequently, identification of the victim wounded by a perforating bullet can reliably be achieved if contamination or removal of evidentiary material by improper handling is prevented. This technique is especially useful in cases where more than one person has fired a gun because the bullet carrying DNA can be linked to the firearm by investigation with a comparison microscope. As a by-product of this investigation, a variant allele 14 (14+4) at the VWA locus was detected.

Alleles↗

Multiple gunshot suicides: potential for physical activity and medico-legal aspects.

Out of 138 clearly defined gunshot suicides which were autopsied, 11 persons (8%) fired two or more gunshots to the body. From these 11, 5 cases involved 2 gunshots to the head where the bullets fired first had missed the brain. The trajectories were restricted to the chest in three cases and a combination of gunshots to the head and chest including two perforating heart wounds without immediate incapacitation occurred in three more cases. Reliable incapacitation is based on physiological effects (tissue disruption) and can only be achieved by decreasing the functioning capability of the CNS. This can be accomplished by direct disruption of brain tissue or indirectly by cerebral hypoxemia from massive bleeding. Targets of immediate incapacitation are restricted to certain CNS areas and targets of rapid incapacitation include the heart, the (thoracic) aorta and the pulmonary artery. Other major blood vessels and major organs (lungs, kidneys, liver, spleen) constitute targets of delayed incapacitation. This general classification can be derived from the literature and is illustrated by the cases presented. A thorough post mortem can exclude or quantify the potential for physical activity. Typical features of single gunshot suicides such as contact shots, classical entrance wound sites and soot/backspatter on a hand also occur in multiple gunshot suicides.

Adult↗

Unusual self-inflicted injuries simulating a criminal offence.

A total of 14 cases with self-inflicted injuries intended to simulate a criminal offence are reported. Typical characteristics of self-infliction such as superficiality, localisation at the anterior aspect, parallel course or avoidance of areas with high sensitivity to pain are substantiated by most of the cases analysed. However, the majority of cases also comprised atypical features including large hematomas of the extremities, a gaping cut wound, lip laceration, hematoma of the eyelids, concussion of the brain, large burn injuries and signs of bonding. Therefore, atypical injuries, which are either found in isolation or in combination with typical injury patterns, cannot exclude self-infliction. Initially, most "victims" did not intend to report the matter to the police but the persons whose affection was to be obtained made the report. Psychopathological motivations are predominant but rational motives such as attempted insurance fraud also occur.

Adolescent↗

Pulmonary myelomonocyte subtypes in drowning and other causes of death.

Three immunohistochemically different myelomonocytic subtypes, i.e. MRP8, MRP14 and 27E10 were quantitatively evaluated in the intraalveolar, alveolar-interstitial and alveolar-intracapillary lung compartments. Lung sections from 5 major groups with defined causes of death, i.e. drowning and death during immersion (DI), cerebral/intracranial haemorrhages (CH), sudden cardiac deaths (SCD), hanging and throttling (HT) and immediate trauma deaths (ITD) were stained and the positive cells counted. The results show clear differences of the cell numbers on average. Among the different compartments the intracapillary cell count exhibits the highest numbers. If the cell counts are compared to the different causes of death, DI shows the highest values and ITD the lowest. The individual values, however, show considerable variations in all compartments and especially in the low cell count range. Within the DI group two subgroups can be differentiated, one having low and the other one having high cell numbers. This can be due to the type of agony, i.e. drowning versus immersion/hydrocution, or to resuscitation attempts or to a combination of both factors.

Adult↗

Two cases of exenteration of the brain from Brenneke shotgun slugs.

A case of extended suicide resulted in two fatalities due to craniocerebral gunshots from a 12-gauge shotgun firing Brenneke shotgun slugs. In each case, the gunshot shattered the skull and the brain and in one case, large parts of the brain including a complete hemisphere were ejected similar to a "Krönlein shot". The location of the trajectory close to the base of the skull, the muzzle gases and the ballistic characteristics of the missile contributed to this rare form of head injury. The high mass and the large diameter of the lead missile do not necessitate a high muzzle velocity to crush large amounts of tissue or to produce an explosive type of head injury. The wadding material and the metal screw attached to the Brenneke slug can be of forensic significance.

Brain Injuries↗

[Differentiation of hunting accident and suicide with rifles].

Criterias for the differentiation between hunting accidents and suicides are explained and discussed. A thorough investigation of this kind should always include autopsy, examination of the firearm, determination of the shooting distance and examination of the scene including an effort to reconstruct the events. Typical findings in suicides are contact shots, entrance wounds of the head, chest or upper abdomen, downward trajectories and evidence (gunshot residue, backspatter) suggesting a hand had been used to steady the muzzle. Typical findings in hunting accidents are entrance wounds of the extremities, the lower abdomen or the back, worn out or defective safety devices, upward trajectories and trajectories that are incompatible with possible and intended positions of the firearm. Each case has to be examined individually and the findings should be interpreted as an entity.

Accidents↗

Backspatter from experimental close-range shots to the head. I. Macrobackspatter.

Backspatter is the ejection of biological material from a gunshot entrance wound against the line of fire. This phenomenon was investigated experimentally in transverse gunshots to the heads of calves (n = 9) using two types of 9 mm Parabellum ammunition from shooting distances of 0-10 cm. The resulting bloodstains were documented on white paper placed horizontally 60 cm below the impact site. In this report the analysis was restricted to stains with a diameter > 0.5 mm. Backspatter was documented after every gunshot. The number of stains varied from 31-324 per gunshot and appeared to be independent of the shooting distance. The maximum distance droplets travelled varied from 72-119 cm. The majority of droplets accumulated between 0 and 50 cm. The number of droplets and the distances travelled should be higher in man for anatomical reasons. The direction a single droplet can take comprises every possible angle between the most tangential ones to the skin surface. This resulted in a semi-circle of 180 degrees covered with stains. Skin ruptures of the entrance wound were not observed. The succession of events was documented on high speed film and started with the recoil of the firearm, immediately followed by a blow-out effect of the skin. Large droplets exited approximately 0.7-4 ms after the bullet impacted the skin. The calculated minimum initial velocity of these droplets was 13-61 m/s. Backspatter from gunshots to the head likely is caused by the hot gases expanding subcutaneously and by cavitation-related intracranial overpressure and tail splashing. In three out of nine gunshots, secondary backspatter additionally occurred as a result of droplets produced by a stream of blood from the entrance wound impacting the paper surface.

Animals↗

On the physics of momentum in ballistics: can the human body be displaced or knocked down by a small arms projectile?

Shooting incidents are often portrayed as resulting in a sometimes violent backwards displacement of the victim. This opinion is also not infrequently held by expert witnesses. The physical force responsible for this would be momentum (mass x velocity). The physics of momentum in ballistic injury is explained in detail. The maximum momentum transferred from different small arms projectiles including large calibre rifles and a 12-gauge shotgun only results in a backwards motion of a 80 kg target body of 0.01-0.18 m/s, which is negligible compared to the velocity of a pedestrian (1-2 m/s). Furthermore, counterbalance is constantly maintained by neurophysiological reflexes. So the effect of the momentum transferred from the missile is virtually zero and there is no backwards motion of the person shot. Empirical evidence verifying these calculations can be obtained from hunting big game, from human gunshot victims and from a video documentary demonstrating the lack of any backwards motion of a person wearing body armour after hits from a centre fire rifle. So the alleged backwards hurling of a person shot is nothing but a myth which should be refuted not only because it is incorrect but also because it can result in miscarriages of justice.

Expert Testimony↗

DNA typing of cellular material on perforating bullets.

DNA typing of cellular debris from perforating bullets was investigated following shooting experiments. A total of 14 perforating gunshots were fired into 9 calves. PCR typing of tissue fragments was done using bovine-specific primers flanking a 247 bp segment within the bovine lactoglobulin gene. Positive amplification results were obtained for all 9 hollow point (HP) and all 5 full metal jacket (FMJ) bullets. In contrast to HP bullets the smooth surfaces of the FMJ bullets did not have visible biological material, which resulted in weaker bands in the DNA analysis compared to HP bullets. Tissue seemed to accumulate at the base of the projectiles. Due to the lack of a suitable marker in bovines, only a species identification was carried out on the DNA from tissue on the bullets. The small amount of DNA extract (up to 5%) required for specification is promising for the successful application of a set of short tandem repeat (STR) systems for individualization in humans. By individualizing tissue on perforating bullets, the bullet and the victim it passed through can be linked. This can assist the investigation of gunshot deaths, especially when several persons are involved in a gun fight.

Animals↗

Firearm fatalities and injuries from hunting accidents in Germany.

Accidental hunting firearm injuries and fatalities (257 cases from 1961 to 1992) were evaluated in detail. Most persons responsible for the accident were more than 40 years old and experienced in hunting, and 26% of the gunshot wounds were fatal. In 77% of cases the victim was shot by another person and in 23% the wound was self-inflicted. The firearms/ammunition used were pellets from shotguns (63%), bullets from rifles (31%), shotgun slugs (3.5%) and bullets from handguns (2.5%). In 22% of all accidents from pellets severe eyeball injuries were involved, and 38% of the wounds were caused from a distance of 5 m or less, including all self-inflicted injuries. The most frequent factors responsible for the accident were: improper handling of the firearm (37%), failure to notice the victim (24.1%), covering the victim while swinging on the game (14.8%), ricocheting projectiles (13.6%), inadequate storage of the firearm (11.7%) and mistaking the victim for game (9.3%). In some cases more than one factor contributed to the accident. Defective firearm/ammunition, as the only non-human factor, was involved in only 1.6% of accidents. Some aspects of the prevention and the forensic investigation of hunting accidents are discussed.

Accidents↗

[Left-sided flank pain in coincident infrarenal aortic aneurysm and left-sided nephropathy].

Two cases illustrating the difficult differential diagnosis of left-sided pain in the coincidence of nephropathy and aortic aneurysm are described. In both cases an aortic aneurysm was discovered, although the aneurysm caused the pain in the side in only one case. In particular, older men with recently occurring side or back pain must be examined with regard to aortic aneurysm. As the classic symptoms of a ruptured aneurysm are frequently disguised, aneurysm must always be considered as a cause of left-sided pain.

Aged↗

Suicide with a signal pen gun.

A man committed suicide with a modified signal pen gun and a .22 lr HV HP bullet. The contact shot to the left chest led to a conventional entrance wound. The projectile from the unconventional weapon caused a penetrating wound and was not deformed instead of the expected perforation and deformation. The smooth-bore barrel did not leave characteristic firing marks on the bullet.

Adult↗

Penetrating gunshots to the head and lack of immediate incapacitation. I. Wound ballistics and mechanisms of incapacitation.

There are two distinct mechanisms of ballistic injury. Crushing of tissue resulting in a permanent tract is the primary factor in wounding of most tissues and most body regions. Temporary cavitation causes radial tissue displacement and subsequent shearing, compression and especially stretching of tissue analogous to blunt trauma. In contrast to the effect in elastic tissue, temporary cavitation can contribute substantially to wounding of inelastic tissue, such as the brain. This is the case in penetrating gunshot wounds to the head. Additionally, the penetration of the bony cranium can produce secondary missiles in the form of bone or bullet fragments and a tendency of the bullet to deformation and early yaw. Most important, wounding resulting from temporary cavitation is greatly augmented by the confined space provided by the unyielding walls of the skull. Bone contact and enhanced effects of temporary cavitation result in an enlarged zone of disintegrated tissue and in high intracranial peak pressures. Morphological signs of powerful intracranial pressure effects are cortical contusion zones, indirect skull fractures and perivascular haemorrhages remote from the tract. Depending on ballistic and anatomical parameters, the intracranial effect varies from slightly more severe injury than in isolated soft tissue to an "explosive" type of injury with comminuted fractures of the skull and laceration of the brain. Incapacitation is the physiologically based inability to perform complex and longer lasting movements independent of consciousness or intention. Immediate incapacitation is possible following cranio-cerebral gunshot wounds or wounds that disrupt the upper cervical spinal cord only. Rapid incapacitation can be produced by massive bleeding from major vessels or the heart. Immediate incapacitation is the result of primary intracranial effects of the bullet. A mechanism similar to commotion cerebri applied extracranially does not exist in cases of penetrating gunshot wounds to the head.

Brain↗

Penetrating gunshots to the head and lack of immediate incapacitation. II. Review of case reports.

Because of the enhanced intracranial tissue disruption (see companion paper) and the functional significance of the central nervous system, penetrating gunshot wounds of the head commonly result in immediate incapacitation. However, in the last century numerous publications reported sustained capability to act following penetrating gunshot wounds of the head. These are reviewed. A large number of case reports had to be excluded from re-examination because of doubtful capability to act or lack of morphological documentation. There remained 53 case reports from 42 sources for systematic analysis. Favourable conditions for sustained capability to act are present in cases where the additional wounding resulting from the special wound ballistic qualities of the head (see companion paper) are minimized. Thus, more than 70% of the guns used fired slow and lightweight bullets: 6.35 mm Browning, .22 rimfire or extremely ineffective projectiles (ancient, inappropriate or selfmade). A centre-fire rifle or a shotgun from close range were never employed in cases involving intracerebral tracts. A coincidence of several lucky circumstances made sustained capability to act possible in two cases of military centrefire rifle bullets passing longitudinally between the frontal lobes without direct contact with brain tissue. Only two large handguns resulting in intracerebral wounding were used: one firing a .38 special bullet, which solely wounded the base of the right temporal lobe and one firing a .45 lead bullet, which seriously injured the left frontal lobe but whose trajectory was limited to the anterior fossa of the skull. Of the trajectories, 28% were outside the neurocranium. At least 70% of the craniocerebral tracts passed above the anterior fossa of the skull, wounding the frontal parts of the brain. Apart from a neurophysiological approach, this preference can be explained by the fact that the base of the anterior cranial fossa and the sella turcica area serve as a bony barrier protecting the parts of the brain located in its "shadow"' relative to the trajectory against cavitational tissue displacement and associated overpressures. This is particularly true of the brain stem. Intracerebral trajectories not located above the anterior fossa were caused by slow and lightweight bullets preferring one temporal lobe. Additionally, one parietal and one occipital lobe were each injured once by a very ineffective projectile and by a 7.65-mm bullet reduced in velocity. Not a single case of injury to the brain stem, the diencephalon, the cerebellum or major paths of motor conduction and only one grazing shot of the anterior parts of the nucleus caudatus (basal ganglia) were described. Morphological signs of high intracranial pressure peaks (cortical contusion zones, indirect skull fractures, perivascular haemorrhages) and secondary missiles were poorly documented. It is suggested that these findings are at least very rare and not obvious in cases of sustained capability to act.

Brain Injuries↗

[Use of cartilage transplants in middle ear surgery. A histologic long-term study of cartilage implants].

30 autogenic and allogenic (homologous) cartilage grafts removed from the middle ear after an average time of 9 years and a maximal time of 25 years were studied by light microscopy. Half of the grafts showed signs of cellular vitality. Degeneration and avital cells are predominant in all grafts. Persisting residual vitality does not influence resorption and matrix necrosis in other areas of the graft. More than two thirds show structural changes by cellular resorption, infraction and vascularisation. These changes appear mainly independent of the time elapsed after transplantation. 5 grafts show bone new formation. Circumscript necrosis of the cartilage matrix was seen in 12 grafts. The study indicates that in comparison to ossicles or alloplastic material cartilage is less advisable to be used for the reconstruction of the ossicular chain due to the unpredictable degradation and loss of form stability.

Cartilage↗