Estimation of age in adolescents --the basilar synchondrosis.

The state of fusion of the basilar synchondrosis as a biological age indicator was assessed in a sample of 91 cadavers of both sexes whose ages ranged between 8 and 26 years. The correlation between the degree of closure and chronological age was investigated. Although the female population sample was very small (n = 21), the data indicate a tendency of differences in age between the "open" and "closed" groups. In the male population (n = 70), no significant differences were detected between the "open" and "closed" categories; in fact, the mean age of the two groups was the same (p = 0.9). These findings indicate that the stage of fusion of the basilar synchondrosis is not a good indicator of age in male cadavers, while in females the feature could be useful when estimating age of unknown human remains, although further investigation on a larger sample is advocated.

Strangulation of pregnant woman leads to one first-degree murder indictment for the death of the mother: a medicolegal reconsideration of maternal/fetal/homicide.

A Hispanic woman, 7 1/4, to 7 1/2 lunar months pregnant, was strangled to death by her common-law husband. After receiving information from an informant, a reporter uncovered the remains of the woman and fetus in a grave in a river bank near Eloy, Arizona. The remains were submitted by local law enforcement officials to the forensic pathologist for medicolegal examination. After this analysis, they were turned over to the consulting forensic anthropologist for positive identification of the mother and for fetal age determination to assess possible viability. During the 1970s and 1980s, viability for a fetus of this age was thought possible, although not probable. Prosecution of the common-law husband on the charge of first-degree murder of his wife was successful, whereas a comparable charge for the fetus was not sought. Many issues are raised, including gestational age estimation in relation to fetal viability. Fetal age is reassessed by means of measurements from diaphyseal lengths. These measurements allowed for comparability of fetal age estimations between published studies, with discussion of changing dates of fetal viability made possible through technologic advances. Because fetal viability changes with these advances, it is necessary to establish and update the guidelines for medicolegal practice.

Restriction fragment length polymorphism (RFLP) analysis on DNA from human compact bone.

DNA typing techniques primarily identify specific genetic markers that are highly polymorphic within a population and have found great utility in forensic science. The established DNA identification protocol, termed restriction fragment length polymorphism (RFLP), has been admitted as physical evidence in the investigation of crimes such as assault, sexual assault, and homicide. The limitation associated with this procedure concerns the integrity of the genetic material. This study sought to evaluate human bone as a source material for DNA identification following exposure to common forensic field conditions. Often, with the onset of decomposition and eventual disarticulation of a body, soft tissues, hair and teeth may not be recovered. The significance of this study lies in the fact that, within forensic anthropology, human bone represents the most biologically stable evidence and is sometimes all that remains after periods of exposure. Genomic DNA was extracted from human bone following exposure to surface deposit, shallow burial, and fresh water immersion. Samples were collected over a three month time course and analyzed by spectrophotometry and agarose gel electrophoresis as well as RFLP analysis. The data suggest that high molecular weight DNA may indeed be extracted from human bone and typed by RFLP analysis for use in forensic identification. Under simulated forensic field conditions, the severity of DNA degradation was in the order of fresh water immersion > shallow burial > surface deposit. Genomic DNA from bone deposited on the desert surface for up to 4 weeks was detected by RFLP analysis. No spurious bands were detected in any specimens, and to the extent that bands were still present, the RFLP patterns matched. These findings demonstrate that human bone can be a reliable source of genomic DNA, and that bone recovered from surface deposit is the most desirable for use in forensic identification.

Decay rates of human remains in an arid environment.

The environment of southern Arizona with mild winters and hot, dry summers produces great variability in decay rates of human remains. Summer temperatures, which range well over 38 degrees C (100 degrees F), induce rapid bloating as a result of the accumulation of decompositional gases. However, in certain circumstances, the aridity can lead to extensive mummification, allowing preservation of remains for hundreds of years. A retrospective study of 189 cases, concentrating on remains found on the desert floor or in the surrounding mountains and on remains found within closed structures, outlines the time frame and sequences of the decay process. Remains can retain a fresh appearance for a considerable time in the winter, but the onset of marked decomposition is rapid in the summer months. Bloating of the body usually is present two to seven days following death. Following this, within structures, there is frequently rapid decomposition and skeletonization. With outdoor exposure, remains are more likely to pass through a long period of dehydration of outer tissues, mummification, and reduction of desiccated tissue. Exposure of large portions of the skeleton usually does not occur until four to six months after death. Bleaching and exfoliation of bone--the beginning stages of destruction of the skeletal elements--begins at about nine months' exposure. Insect activity, including that of maggot and beetle varieties, may accelerate decomposition, but this process is greatly affected by location of the body, seasonal weather, and accessibility of the soft tissues. Carnivores and other scavengers also are contributing factors, as are clothing or covering of the body, substrate, elevation, and latitude.

Systems for human identification.

The methods and techniques used in Categories 1, 2, and 3 are the least reliable because of their subjective nature as well as the ever-present potential for human error. These methods are valuable, however, as adjuncts in identification procedures in a total exclusionary and inclusionary comparison. The methods and techniques described in Category 4 have a more scientific basis, but still caution must be used, and, prior to the completion of the death certificate, a complete evaluation should be made of all techniques employed in the identification.

Otosclerotic stapedial footplate fixation in an 18th century burial.

Fixation of the footplate of the stapes by otosclerosis had been found in the left ear of a probable Spaniard who died about 200 years ago and was buried in the Tuscon Presidio. Previous studies on North and South Dakota American Indian crania of about the same time period did not demonstrate any stapedial fixation in 2,600 burials (4,064 temporal bones), 1,416 of which were over 16 years of age at death. The Tucson burial would indicate that this abnormality can be demonstrated in old interred skeletal material. Our other studies suggest that this disease process was not common in the prehistoric and historic Indian populations of the Dakotas.