The timing of histologic changes in liver lacerations.

Microscopic examination was performed on 55 cases of traumatic liver lacerations incurred from fatal motor vehicle accidents. None of the deaths was due to the liver injury. In 38 of 55 cases, the decedent was pronounced dead at the scene. Microscopic examination of the liver lacerations in these 38 cases revealed no histologic changes related to the trauma. In 17 of 55 cases, the decedent was transported to the emergency room (ER) with a "survival time" (from Emergency Medical Service arrival to the time of pronouncement) of 15 minutes to 7 hours and 10 minutes. Nine of these 17 had vital signs at the scene. Five of the 17 had neutrophilic infiltration and hepatocyte necrosis at the site of the laceration. Four of these had vitals signs at the scene. Survival time of the 5 patients with a vital reaction at their liver injury ranged from 51 minutes to 7 hours and 10 minutes.

Heterotopic ossification in unidentified skeletal remains.

Heterotopic ossification is a benign, ectopic bone growth that develops in muscle and other soft tissue. The exact cause is poorly understood, but it is a rarely serious complication of soft tissue trauma. Its most common form, myositis ossifications traumatica, occurs as a secondary complication of direct muscle injury. However, other forms are less common and can result from specific pathologic conditions, such as spinal cord trauma and metabolic disorders. In patients who have had spinal cord injury and subsequent paraplegia, heterotopic ossification often results in ankylosis of the hip and a loss in range of motion. Ectopic ossification occurs below the injury site, and, although the specific muscle groups can vary, it usually involves those for which the origin and insertion involve the anterior pelvis and proximal femur. In dried bone, heterotopic ossification can appear as a smooth, irregularly shaped benign tumor of mature bone, extending from the surface but not invading the cortical bone. These tumors range in size from a few millimeters to several centimeters. Because heterotopic ossification is often associated with specific types of injuries, it has a unique anthropological use in forensic cases.

Suicide by firearms: a 15-year experience.

A retrospective review of 1704 cases of suicide involving firearms investigated by the Bexar County Medical Examiner's office between 1984 and 1998 was performed. The age distribution was similar in male and female victims, and the type of weapon was not associated with age. Approximately 78% of the victims used a handgun (87% of female and 76% of male victims). In 4.0% of head wound cases, the site of the entrance wound was the back of the head. Thus, this report refutes the common belief that all gunshot wounds to the back of the head represent homicides. In 1.9% of the cases, the wounds were inflicted at intermediate range. With handguns, the right temple was the most common site, but with rifles and shotguns, the most common site was the mouth.

Fatal hyperthermia in hot baths in individuals with multiple sclerosis.

The authors report the case of a 47-year-old black man with a history of multiple sclerosis who was found dead in a bathtub, head above water, with a body temperature of 105.7 F. Results of a complete autopsy and toxicologic screen were negative. Individuals with multiple sclerosis, if immersed in hot water, develop motor weakness, which may be so severe as to prevent them from getting out of the water, whether they be in a bathtub or whirlpool bath. In this case, the individual was trapped in a bathtub in which there was a continuous flow of hot water. This overwhelmed an already impaired thermoregulatory mechanism, causing hyperthermia and death.

Homicidal asphyxia.

Homicides due to asphyxia are relatively uncommon. To better understand the presentation of such cases, the files of the Bexar County Medical Examiner's Office were reviewed from January 1, 1985, through December 31, 1998, for all such homicides. A total of 133 cases were found. The largest category was ligature strangulation with 48 deaths (21 male, 27 female). Petechiae were present in the conjunctivae and/or sclerae in 86% of the cases; fractures of the hyoid and/or thyroid cartilage were present in 12.5%. There were a total of 41 deaths from manual strangulation (27 female, 14 male). Petechiae were present in 89% of the cases. In cases of manual strangulation, fractures of the hyoid, thyroid, or cricoid cartilage were found in all the male victims and slightly more than one half of the female victims. Twenty-six cases of suffocation were found; 20 of the victims were < or =2 years of age. Only 1 of these children had petechiae and/or scleral hemorrhage. Five deaths were due to choking. Three of the deaths involved adults who were gagged; 2 deaths involved infants with foreign material pushed into the mouth. Other categories of asphyxia were as follows: 9 deaths due to more than one form of asphyxia; 1 death due to hanging, and 3 deaths due to drowning. Rape was the motive in 66% of the female victims of ligature strangulation and 52% of those due to manual strangulation.

Death due to concussion and alcohol.

We encountered 5 deaths following blunt trauma to the face and head in which the injuries were predominantly soft tissue in nature with absence of skull fractures, intracranial bleeding, or detectable injury to the brain. All individuals were intoxicated, with blood ethanol levels ranging from 0.22 to 0.33 g/dl. We feel that in these deaths, ethanol augmentation of the effects of concussive brain injury, with resultant posttraumatic apnea, was the mechanism of death.

Pressure sores in a Christian Science sanatorium.

We reviewed the Dallas County Medical Examiner's Office records of all individuals who had died in a local Christian Science Sanatorium during a 5 1/2-year period. Of 116 such patients, only 13 (11%) had pressure sores (decubitus ulcers). In 10 of these patients, the sores were described as small, superficial, and/or healing, while the other three patients had more serious ulcers. In contrast, for patients dying in nursing homes or hospitals, the incidence of pressure sores may be as high as 54-57%. It is our opinion that the difference in incidence is due to the personal and conscientious nursing care provided by Christian Science institutions.

Deaths caused by carbon monoxide poisoning in an open environment (outdoors).

Three deaths as a result of inhalation of carbon monoxide from the exhaust fumes of automobiles are reported. All deaths occurred outside and not in a structure. The individuals were white males, ages 24 to 26 years. Blood carboxyhemoglobin concentrations ranged from 58 (in a decomposing body) to 81%. The three cases illustrate the fact that even in the outdoors death from carbon monoxide inhalation can occur if an individual is in close proximity to a rich source of carbon monoxide.

Sudden, unexpected death due to massive, nontraumatic intra-abdominal hemorrhage in association with cirrhosis of the liver.

Hemoperitoneum is usually due to rupture, laceration, or perforation of a blood vessel or organ. The author describes three deaths due to massive intra-abdominal hemorrhage, all in alcoholics with cirrhosis of the liver, in which no source for the bleeding was found. One of the three individuals, who was briefly hospitalized, showed evidence of a disseminated intravascular coagulopathy (DIC). In the author's opinion, this is the most likely cause of the intra-abdominal hemorrhage in the two other cases and is related to the cirrhosis of the liver.

Use of scanning electron microscopy and energy dispersive X-ray analysis (SEM-EDXA) in identification of foreign material on bullets.

The authors report two cases in which examination of foreign material embedded in or adherent to bullets provided critical information in the reconstruction of a crime scene. Analysis of small particles by scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDXA) can be accomplished without destruction or injury of the particles. In one case, the detection and identification of mineral fragments embedded near the nose of a bullet provided conclusive evidence that the bullet had ricocheted from a fireplace before striking the victim. In the second case, analysis of particles from two bullets identified them as them as bone fragments, thus proving which shots fired from a police officer's gun had killed a suspected burglar. SEM-EDXA has not been widely used to identify such material on bullets, but should be considered a potentially powerful tool in forensic science.

The behavior of the expanding point .25 ACP ammunition in the human body.

We examined six cases (four homicides, two suicides) involving gunshot wounds with .25 ACP ammunition. The nature of these cases is described in this article.

A fatal case of lead poisoning due to a retained bullet.

Lead poisoning from a retained bullet or missile is rare and is usually dependent on the location of the missile in a bone or immediately adjacent to a joint. A review of the literature revealed only 14 cases in which there was adequate laboratory documentation of plumbism caused by a retained bullet or missile. Only one of these previously reported cases resulted in death. We report a second death due to lead poisoning from a retained bullet with elevated blood lead levels documented by toxicologic analysis.

Death by poisoning: a ten-year survey of Dallas County.

From 1971 through 1980, 1115 deaths were ascribed by the Dallas County Medical Examiner's Office to poisoning of some type. An analysis of these deaths, with emphasis on the substances involved, is the purpose of this study. Relatively few agents or groups of agents accounted for 87% of these deaths: carbon monoxide, barbiturates, propoxyphene, narcotics, tricyclic antidepressants, ethyl alcohol, and inhalants (gases and solvents). Twenty-five percent of the deaths were classified as mixed intoxications, resulting from combinations of agents. Two major trends were observed: in the second five-year period, barbiturate-induced deaths decreased considerably (58%) and deaths from tricyclic antidepressants increased more than four times as compared with the first five-year period. Yearly statistics have been compiled for deaths from each agent.

Minimal velocities necessary for perforation of skin by air gun pellets and bullets.

A series of tests were conducted to determine the velocities necessary for lead air gun pellets (calibers .177 and .22) and caliber .38 lead bullets to perforate skin. Human lower extremities were used. Caliber .177 air gun pellets weighing 8.25 grains required a minimum velocity of 101 m/s (331 ft/s) to perforate skin. The energy per area of presentation ratio E/a was 1:86 m X kg/cm2. Caliber .22 air gun pellets weighing 16.5 grains needed a minimum velocity of 75 m/s (245 ft/s). The E/a was 1:3 m X kg/cm2. A round nose, caliber .38 lead bullet weighing 113 grains perforated skin at 58 m/s (191 ft/s). The E/a was 1.95 m X kg/cm2. These studies appear to indicate that lightweight projectiles need greater velocity to perforate skin than do larger caliber, heavier bullets.

Drug detection at autopsy: a prospective study of 247 cases.

Comprehensive toxicology analyses using gas chromatography of blood for alcohol and acidic, basic, and neutral drugs were performed on 247 randomly selected medical examiner cases. Drugs or alcohol or both were found in 54% of this group. When considered by manner of death (natural, accident, homicide, and suicide), each of the groups had incidences of positive findings of 46 to 63%. Selection of cases for toxicologic study on the basis of manner of death does not seem to be feasible. It is the authors' opinion that comprehensive toxicology evaluation for drugs should be done on virtually all medical examiner cases. This approach ensures a thorough and complete evaluation in all cases. In addition, a comprehensive toxicology study will provide information in the event that questions concerning the absence or presence of drugs arise at some later date.

Penetration and perforation of skin by bullets and missiles. A review of the literature.

A review of the literature on perforation of skin by bullets and missiles indicates that there is a range of velocity below which a missile cannot perforate the skin. Velocities of between 38.1 and 61.6 meters/second (125 and 202 ft./second) will produce at least minimal damage to the surface of the skin, though without perforation. In order for a missile to perforate the skin and enter the underlying subcutaneous tissue and muscle, a minimum velocity in the order of 70 meters/second (230 ft./second) is necessary with an energy/area of presentation of approximately 2.1 m-kg/cm2.