A Review of osteological remains submitted for forensic examination in south Australia over a 7-year period (2013-2019).

The files of the Pathology section of F Forensic Science South Australia (FSSA) Adelaide, Australia were examined over a seven-year period from January 2013 to December 2019 for all cases where skeletal remains had been submitted for assessment. There were 150 cases comprising 79 non-human (53%), 49 traditional Australian Aboriginal (33%) and 12 Coronial (8%). The remaining cases included anatomically prepared skeletal remains or other historic remains, and four cases which were subsequently determined to be non-osseous. The large number of domestic animal bones found reflects the agricultural nature of much of the state in addition to historical urban butchering practices. The next largest category was that of indigenous remains associated with the long history of Aboriginal occupation. Established protocols ensure that this culturally-sensitive skeletal material is passed on to the appropriate traditional community leaders. This study shows the unique range of skeletal materials that is currently being forensically assessed in South Australia and the varied medicolegal implications of each category.

A comparison of crystal structure in fresh, burned and archaic bone - Implications for forensic sampling.

Standard protocols for extracting DNA from bone are variable and are largely dependent on the state of preservation. In archaic samples, endogenous DNA is believed to be tightly bound to crystal aggregates in the Hydroxyapatite (HAp) matrix requiring prolonged demineralisation to allow its release. By comparison, fresh bone contains abundant cellular material, discounting the need for demineralisation. Recommendations for incinerated bone, specifically how viable sampling sites should be selected and the ideal techniques for DNA recovery are unclear, and the protocol used is often selected based on macroscopic sample appearance. It has been postulated that like archaic bone, burned bone is 'highly degraded' and therefore aDNA techniques may present better results for DNA recovery than using fresh protocols. However, little research has been undertaken comparing the crystal structure of burnt, fresh and archaic bone. This study uses a combination of XRPD and SEM analysis to compare the crystalline profile and microscopic appearance of burned bone subjected to temperatures ranging from 100-1000°C, with archaic and fresh samples. Although macroscopically visually different, fresh samples and samples heated up to 500°C showed no microscopic differences or significant changes in crystallinity. By comparison, samples heated above 500°C became significantly more crystalline, with HAp crystal size increasing dramatically. Archaic samples were different again, more closely resembling the amorphous fresh samples than the highly crystalline incinerated samples. These results suggests that, potentially, samples burned at 500°C or lower can be treated as fresh samples, whilst samples exposed to higher temperatures may require adapted protocols. Whether or not these highly burned samples require demineralisation needs to be investigated.

Arid Climate Adipocere-The Importance of Microenvironment.

Skeletal remains were retrieved from a cave in an arid desert environment. The submitted material consisted of dried grass, soil, and malodorous skeletal remains wrapped in leather. After examination, it was revealed that the smell had not been due to recent decomposition but to adipocere. The cause of death was listed as "undetermined" and a suggested date of death as "unknown." Although adipocere usually requires a damp environment or submersion in water to develop, this case provides further evidence for the rare possibility of adipocere formation in an otherwise very dry environment. Wrapping of the body in leather material had produced an impermeable barrier which had sequestrated and preserved bodily fluids allowing anaerobic decay with fat hydrolysis and adipocere formation. Microenvironments may have potentially significant and quite idiosyncratic effects on decompositional processes which may initially confuse investigations.

A risk-based approach to cognitive bias in forensic science.

Over the past decade, the potential impact of cognitive bias in forensic science has instigated much discussion and debate between academics, scientists and those in the justice sector. Evidence of bias influencing subjective decision-making across a range of forensic disciplines has been described in the literature. Forensic service organisations are being urged to address cognitive bias in subjective decision-making by designing processes or procedures to limit access to (irrelevant) contextual information or reduce dependence on cognitive functions. Although some laboratories have implemented bias mitigating strategies, with varying impact on operational efficiency, there has been no systematic assessment of the risk posed by cognitive bias. Forensic Science SA assessed the potential impact of bias on forensic interpretations across multiple disciplines, using a risk management framework. This process proved useful in assessing the effectiveness of existing bias mitigating strategies and identified the latent level of risk posed. While all forensic organisations should seek to implement bias limiting measures that are simple, cost-effective and do not adversely impact efficiency, using a risk-based approach has contextualised the limited benefit of introducing resource hungry measures, as postulated in the literature. That is not to suggest that forensic organisations should dismiss the potential influence of cognitive bias but they need to strike an appropriate balance between risk and return, as they do with any business risk.

Growth Patterns and Individual Variation in Mid-sagittal Facial Soft Tissue Depth from Childhood to Adulthood.

Previous studies have used longitudinal samples to investigate growth of the skeletal aspects of the face, although far less has been done on facial soft tissue. This study uses a larger sample than previous studies on the same data (Denver and Fels growth series) to explore covariation of bony and soft facial dimensions comprehensively from childhood to adulthood. A total of 1036 lateral cephalometric radiographs were digitized from 60 individuals, and distances between facial landmarks were measured using ImageJ. Multivariate analysis of variance (MANOVA) showed all bony facial landmark distances were significantly different (p > 0.05) between age groups; however, only half were significantly different between sexes. Further analysis showed the effect of age (calculated as eta-squared) explained a greater percentage of total variation (20%) than sex (15%). Overall, soft tissue changes between 0 and 19 years of age were small (<3 mm) and only some were correlated to underlying facial skeleton dimensions.

The utilization of incinerated hip and knee prostheses for identification.

PURPOSE: The aim of this study was to test various methods of retrieving number data from hip and knee implants from cremated human remains and to validate our findings by cross referencing our results with the national joint replacement registry. METHOD: Implants were collected from the remains of individuals who had donated their bodies to science following routine planned cremation. A number of different chemical and physical methods to expose the implant numbers on cremated implants to the point that they were legible were tested. The retrieved data on the implants was referred to the Australian Orthopaedic Association National Joint Replacement Registry to identify the individuals, and the names were cross-referenced from the original list of donors. RESULTS: It was possible to retrieve sufficient data from cremated implants to track the name of the recipient of implants if they were placed following the formation of the registry. Both wet and dry paper (1200 size and without moisture), and fine grade steel wool (used in antique restoration), were successful in removing the oxidized layer from implants. With hip implants, it was discovered that the best area to retrieve clear readable information is inside the ball head or at the end of the neck as this area is protected from oxidation during incineration. CONCLUSION: Incinerated or cremated hip and knee implants may be used to assist in the identification of a decedent following careful treatment, in conjunction with national joint revision registries and company data.

Facial soft tissue depth statistics and enhanced point estimators for craniofacial identification: the debut of the shorth and the 75-shormax.

Several methods that have customarily been used in craniofacial identification to describe facial soft tissue depths (FSTDs) implore improvement. They include the calculation of arithmetic means for skewed data, omission of concern for measurement uncertainty, oversight of effect size, and misuse of statistical significance tests (e.g., p-values for strength of association). This paper redresses these limitations using FSTDs from 10 prior studies (N = 516). Measurement uncertainty was large (>20% of the FSTD), skewness (≥ 0.8) existed at 11 of the 23 FSTD landmarks examined, and sex and age each explained <4% of the total FSTD variance (η(2) calculated as part of MANOVA). These results call for a new and improved conceptualization of FSTDs, which is attained by the replacement of arithmetic means with shorths and 75-shormaxes. The outcomes of this implementation are dramatic reduction in FSTD complexity; improved data accuracy; and new data-driven standards for casework application of methods.

Facial soft tissue depths in craniofacial identification (part II): An analytical review of the published sub-adult data.

Prior research indicates that while statistically significant differences exist between subcategories of the adult soft tissue depth data, magnitudes of difference are small and possess little practical meaning when measurement errors and variations between measurement methods are considered. These findings raise questions as to what variables may or may not hold meaning for the sub-adult data. Of primary interest is the effect of age, as these differences have the potential to surpass the magnitude of measurement error. Data from the five studies in the literature on sub-adults which describe values for single integer age groups were pooled and differences across the ages examined. From 1 to 18 years, most soft tissue depth measurements increased by less than 3 mm. These results suggest that dividing the data for children into more than two age groups is unlikely to hold many advantages. Data were therefore split into two groups with the division point corresponding to the mid-point of the observed trends and main data density (0-11 and 12-18 years; division point = 11.5 years). Published sub-adult data for seven further studies which reported broader age groups were pooled with the data above to produce the final tallied soft tissue depth tables. These tables hold the advantages of increased sample sizes (pogonion has greater than 1770 individuals for either age group) and increased levels of certainty (as random and opposing systematic errors specific to each independent study should average out when the data are combined).

Facial soft tissue depths in craniofacial identification (part I): An analytical review of the published adult data.

With the ever increasing production of average soft tissue depth studies, data are becoming increasingly complex, less standardized, and more unwieldy. So far, no overarching review has been attempted to determine: the validity of continued data collection; the usefulness of the existing data subcategorizations; or if a synthesis is possible to produce a manageable soft tissue depth library. While a principal components analysis would provide the best foundation for such an assessment, this type of investigation is not currently possible because of a lack of easily accessible raw data (first, many studies are narrow; second, raw data are infrequently published and/or stored and are not always shared by some authors). This paper provides an alternate means of investigation using an hierarchical approach to review and compare the effects of single variables on published mean values for adults whilst acknowledging measurement errors and within-group variation. The results revealed: (i) no clear secular trends at frequently investigated landmarks; (ii) wide variation in soft tissue depth measures between different measurement techniques irrespective of whether living persons or cadavers were considered; (iii) no clear clustering of non-Caucasoid data far from the Caucasoid means; and (iv) minor differences between males and females. Consequently, the data were pooled across studies using weighted means and standard deviations to cancel out random and opposing study-specific errors, and to produce a single soft tissue depth table with increased sample sizes (e.g., 6786 individuals at pogonion).

Diagnostic yield and characteristic features in a series of decomposed bodies subject to coronial autopsy.

A study was undertaken of 629 cases autopsied at Forensic Science SA, Adelaide, Australia over a 10-year period from 1994 to 2004 where significant decomposition had been documented. The age range of victims was 10 months to 92 years (mean 51.5 +/- 18.1 years). There were 498 males (79%) and 131 females (21%) (M:F = 3.8:1). Deaths in 289 of the 629 cases (46%) were due to natural causes, with 179 suicides (28%), 83 accidents (13%), and 36 homicides (6%). The cause of death was ascertained in 89% of cases and the manner of death in 93% of cases. In 35 cases (6%) both the cause and manner could not be determined. Numbers of suicides were higher in younger age groups while deaths from organic illnesses predominated in later life. The number of cases in summer was significantly greater than in winter. Despite technical difficulties in handling decomposed bodies, and artifactual alteration of tissue structure and microscopic features, the autopsy was still a useful diagnostic exercise. While it is likely that more information may be gleaned from fresh bodies in perfectly preserved states, decomposed bodies may reveal significant anatomical and pathological features that enable both the cause and manner of death to be established.

The identification of submerged skeletonized remains.

Examination was undertaken of skeletonized remains contained within 2 rubber boots dredged by a fishing boat from a depth of 145 m, approximately 185 km off the southern Australian coast in the Great Australian Bight. The boots had been manufactured in Australia in July 1993 and were of a type commonly used by local fishermen. Examination of the lower legs and feet revealed well-preserved bones with arthritic changes in keeping with an older male. DNA analyses using reference samples taken from relatives of fishermen who had disappeared in the area resulted in the identification of the victim as a 52-year-old prawn fisherman who had been swept off a boat over a decade earlier. DNA stability had been maintained by the low light, cold temperatures, and alkaline pH of the ocean floor. Integration of pathologic, anthropologic, and biologic analyses with police investigations enabled a positive identification to be made despite the unusual nature of the location of the remains and the time lapse since the disappearance of the victim.

Role of orthopedic implants and bone morphology in the identification of human remains.

When conventional methods of identification, such as visual recognition and dental comparison, cannot be used to identify a deceased person, it becomes necessary to consider alternative methods. The presence of an orthopedic implant in a body may assist identification if ante-mortem medical records are available for comparison. Another method of identification involves comparison of ante-mortem and postmortem radiographs. Eight cases are reported from Forensic Science SA where the presence of orthopedic implants and/or ante-mortem radiographs were used to try to establish identification. In six cases, positive identification was established, and in two cases with upper limb orthopedic implants, the bones remained unidentified. Manufacturers were unable to provide any information about the distribution and use of the implants that could be of use with identification, as there are no requirements in Australia for individual medical implants to be tracked. Such a system has the potential to aid postmortem identification if serial codes were etched onto implants that could then be traced to manufacturers, surgeons, and recipients of these devices.

Fatal electrocution in adults--a 30-year study.

A retrospective study was undertaken of all cases of death in adults (>16 years) due to electrocution which were autopsied at Forensic Science SA, Adelaide, Australia, over a 30-year period from 1973 to 2002. A total of 96 cases were identified with 87 males (91%) (mean age=41.6 years; range 17 to 86 years) and nine females (9%) (mean age=49.2 years; range 20 to 76 years). Deaths were due to accidents in 66 cases (69%; M:F = 63:3), suicides in 28 cases (29%; M:F=24:4) and homicides in two cases (2%). Both homicide victims were females, with females accounting for only 5% of the accidents and 14% of suicides. The number of accidental deaths increased until the early 1990s and then declined, whereas suicidal electrocutions were only found in the last 20 years of the study. Most deaths (N = 80; 83%) were due to low voltage circuits (<1000 volts), with deaths due to high voltages occurring in 15 cases (16%). One death was due to lightning (1%). While suicides were evenly distributed throughout the year, most accidental deaths occurred in late spring and summer (N = 42; 64%) with the lowest number of accidental deaths occurring in winter and early spring. This report demonstrates a significantly higher rate of electrocution deaths among males, with a summer predominance of accidental deaths, most likely due to increased outdoor activities in better weather. The reduction in cases over the last decade of the study may be a reflection of the success of workplace and domestic safety campaigns. Female electrocution suicides and electrocution homicides were rare events.

Drowning, haemodilution, haemolysis and staining of the intima of the aortic root-- preliminary observations.

In order to demonstrate that hyponatraemia due to haemodilution occurs within the left ventricle following freshwater drowning, and to determine whether lysed blood resulting from left ventricular haemodilution may cause staining of the aortic intima, the following studies were undertaken. Measurements of left ventricular sodium levels were performed in 74 consecutive coronial cases where death was attributed to drowning, consisting of 44 and 30 deceased who were believed to be victims of freshwater and saltwater drowning, respectively. Left ventricular sodium levels differed significantly between the two groups (p<0.001), with a range of 93-147 mmol/L in freshwater drowning (mean=117+/-14.2 mmol/L) and 123-183 in saltwater drowning (mean=153+/-14.4 mmol/L). In addition, the mean sodium level of 117 mmol/L in freshwater drowning was significantly lower than the standard range of 137-145 mmol/L. In a second study, portions of aorta and pulmonary trunk from a euthanised pig were soaked in lysed blood resulting in marked haemolytic staining of the intima of both vessels after 20 min. Water and a mixture of blood and water were then injected into the left ventricles in two further pig carcasses, respectively, resulting in haemolytic staining of the intima of the aortic roots, with no staining of the pulmonary trunks. These studies have confirmed that significant hyponatraemia secondary to haemodilution may occur within the left ventricle in freshwater drowning, and that haemolysed blood is capable of causing staining of the aortic root in an animal model. These results provide further data to support haemolytic staining of the aortic root intima as a possible manifestation of freshwater drowning.

The pathological features and circumstances of death of lethal crush/traumatic asphyxia in adults--a 25-year study.

A 25-year retrospective study of cases of crush/traumatic asphyxia autopsied at Forensic Science SA, Adelaide, Australia from 1980 to 2004 was undertaken. A total of 79 cases of crush asphyxia was found consisting of 63 males (80%) and 16 females (20%). The age range of the males was 19-86 years (mean=41.8 years) and of the females was 19-75 years (mean=38.6 years). In 18 cases the exact circumstances of death were unclear, leaving 61 cases in which details of the fatal episode were available. Major categories included vehicle crashes (N=37), industrial accidents (N=9), farm accidents (N=6) and entrapment beneath vehicles (N=5). Forty of the 79 victims (51%) had only very minor bruises and abrasions; 28 (35%) had evidence of chest compression with rib and sternal fractures and large areas of soft tissue bruising of the chest; 7 cases (9%) had other significant injuries or findings that had contributed to death. All of these victims had signs of crush asphyxia in the form of intense purple congestion and swelling of the face and neck, and/or petechial hemorrhages of the skin of the face and/or conjunctivae. The pattern of pathological findings of crush asphyxia was not influenced by the presence or absence of concomitant serious or lethal injuries. In 4 cases (5%) where the circumstances of the lethal episode were those of crush asphyxia there were no characteristic pathological findings. This study has shown that a high percentage of crush asphyxias may be caused by vehicle accidents. It has also demonstrated that on occasion fatal crush asphyxia may have to be a diagnosis of exclusion, made only when there are characteristic death scene findings, and no evidence of lethal natural diseases or injuries at autopsy, with negative toxicological screening.

Temporal trends over the past two decades in asphyxial deaths in South Australia involving plastic bags or wrapping.

Asphyxial deaths utilising plastic bags or wrappings occurring over a 20-year period from March 1984 to February 2004 were reviewed at Forensic Science SA, Australia. A total of 45 cases were identified, with three occurring in infants and children (one accidental asphyxia; two homicides). Of the remaining 42 adults the male to female ratio was approximately 1:1 (23 and 19 cases, respectively), with all deaths attributed to suicide. The 42 adult cases represented 1.2% of the 3569 suicides autopsied at the centre over the time period of the study. The age ranges of the adult victims were 19-88 years (mean=47.1 years) for the males, and 32-89 years (mean=60.5 years) for the females. The adult female victims were significantly older than the males (p<0.001). A number of victims had histories of depression and had taken prescription medications. A significant difference was found in the temporal occurrence of the adult deaths, with six cases occurring between 1984 and 1989, nine between 1989 and 1994, 11 between 1994 and 1999, and 16 between 1999 and 2004 (p<0.001). Plastic bag asphyxial deaths were rare and in adults were due to suicide involving either older females or younger males. A significant increase in cases in South Australia in recent years was demonstrated, possibly related to publicity surrounding assisted suicides, and the ready availability of suicide manuals and information on suicide techniques from the internet.

Characteristic acquired features of indigenous australians that may be observed in forensic practice.

Australian aboriginal people who are living in traditional groups often have a variety of characteristic acquired features that distinguish them from those who have been resident in less traditional communities. These features include particular forms of scarification, tooth avulsion, and subincision of the penis. Skeletonized remains may also show acquired features such as marked dental attrition, parry fractures, and squatting notches of the long bones. Once features have been found at autopsy to indicate that the deceased may have come from a traditional aboriginal background, one can check for particular conditions with a high prevalence in tribal communities. Additionally, standard reporting practices may be modified to assist in traditional practices and rituals. The identification of a skeleton as aboriginal often means that the burial was historical and that a concealed homicide with body disposal is unlikely. Steps can then be taken to ensure that the remains are returned to aboriginal people/traditional landowners who will be able to re-inter the bones in a manner that is culturally sensitive and appropriate to their needs and belief systems.

Measurement of protein-like fluorescence in river and waste water using a handheld spectrophotometer.

Protein-like fluorescence intensity in rivers increases with increasing anthropogenic DOM inputs from sewerage and farm wastes. Here, a portable luminescence spectrophotometer was used to investigate if this technology could be used to provide both field scientists with a rapid pollution monitoring tool and process control engineers with a portable waste water monitoring device, through the measurement of river and waste water tryptophan-like fluorescence from a range of rivers in NE England and from effluents from within two waste water treatment plants. The portable spectrophotometer determined that waste waters and sewerage effluents had the highest tryptophan-like fluorescence intensity, urban streams had an intermediate tryptophan-like fluorescence intensity, and the upstream river samples of good water quality the lowest tryptophan-like fluorescence intensity. Replicate samples demonstrated that fluorescence intensity is reproducible to +/- 20% for low fluorescence, 'clean' river water samples and +/- 5% for urban water and waste waters. Correlations between fluorescence measured by the portable spectrophotometer with a conventional bench machine were 0.91; (Spearman's rho, n = 143), demonstrating that the portable spectrophotometer does correlate with tryptophan-like fluorescence intensity measured using the bench spectrophotometer.

Variation in soft-tissue thicknesses on the human face and their relation to craniometric dimensions.

The average thickness of soft tissues on parts of the face is known, but its variation has not been related to cranial morphology. To investigate this relationship, measurements of facial soft-tissue depths and craniometric dimensions were taken on adult, white Australian cadavers (17 male and 23 female). Significant correlations between many soft-tissue depths and craniometric dimensions were found, suggesting a relationship between the amount of soft tissue present on the face and the size of the underlying bony skeleton. Soft-tissue depths were highly positively correlated with each other; craniometric dimensions were correlated but to a lesser extent. Males had thicker soft tissues and larger craniometric dimensions than females; considerable overlap of ranges was also noted. Multiple regression analysis was used to produce equations predicting the soft-tissue depth at specified areas of the face from craniometric dimensions. A subsample of nine cadavers was examined for the effects of tissue embalming. Embalming caused significant initial increases in facial soft-tissue depths. Cadavers embalmed for less than 6 months had soft-tissue depths significantly greater than for fully embalmed cadavers. The evidence that facial soft-tissue thicknesses vary with craniofacial dimensions has implications for forensic identification, facial aesthetic surgery, and approximation of the facial features of extinct individuals.