西南地区成人男性颅骨的相关回归分析

目的研究颅骨部分测量指标间的相关性,以期建立在对破损颅骨进行颅骨面貌复原时,利用尚存指标推断缺失指标的方法。方法用人体骨骼测量仪对41个男性颅骨的颅长、颅宽、颅高等14个指标进行测量,将测量值输入SPSS统计软件,找出相关性好的指标,建立各指标间相互推断的回归方程。结果部分测量指标间呈中度以上相关,应用逐步回归的方法得出回归方程24个,方差检验均具统计学意义(P<0.01)。结论本研究所建立的回归方程可为法医人类学和考古人类学的颅骨修复提供备选方法。     

The Application of the Central Limit Theorem and the Law of Large Numbers to Facial Soft Tissue Depths: T‐Table Robustness and Trends since 2008,

By pooling independent study means (), the T‐Tables use the central limit theorem and law of large numbers to average out study‐specific sampling bias and instrument errors and, in turn, triangulate upon human population means (μ). Since their first publication in 2008, new data from >2660 adults have been collected (c.30% of the original sample) making a review of the T‐Table's robustness timely. Updated grand means show that the new data have negligible impact on the previously published statistics: maximum change = 1.7 mm at gonion; and ≤1 mm at 93% of all landmarks measured. This confirms the utility of the 2008 T‐Table as a proxy to soft tissue depth population means and, together with updated sample sizes (8851 individuals at pogonion), earmarks the 2013 T‐Table as the premier mean facial soft tissue depth standard for craniofacial identification casework. The utility of the T‐Table, in comparison with shorths and 75‐shormaxes, is also discussed.     

Discrimination of falls and blows in blunt head trauma: systematic study of the hat brim line rule in relation to skull fractures

In the discrimination of falls from blows in blunt head trauma, the hat brim line rule is one of the most often used criteria. The present study assesses the validity of the hat brim line rule for skull fractures and looks at other possible criteria. All autopsy cases were retrospectively analyzed on a 5-year period. Cases selected consisted of downstairs falls (n = 13), falls from one's own height (n = 23), and homicidal blows (n = 44). Results show that fractures above the hat brim line are more in favor of blows, while fractures in the hat brim line zone are more difficult to distinguish. The majority of fractures were located on the left side for homicidal blows and on the right side for falls. A higher average number of lacerations was revealed for homicidal blows. In conclusion, this study establishes three criteria in favor of blows: (i) localization of a wound above the hat brim line; (ii) left side lateralization; and (iii) a high number of lacerations.     

Recent human sexual dimorphism study using cephalometric plots on lateral teleradiography and discriminant function analysis

Abstract:  The examination of skull sexual dimorphism has been the subject of numerous morphologic and craniometric studies, but the disadvantage of these studies is that they are dependent on the experience of the operator and involve subjectivity. In 1996, a team from Taiwan refined the methods enabling the sex of an individual to be determined using cephalometric plots made from lateral teleradiography. To validate their work using a European population, 114 dry skulls (59 men and 55 women) were examined. Cephalometric plots were made on lateral teleradiography with an orthodontic software and 18 cephalometric variables were analyzed. Sex was determined with 95.6% accuracy using the 18 variables discriminant function. A subset of eight variables was selected and could predict sex with the same accuracy. In conclusion, it can be said that skull-sexing methods using lateral teleradiography seem always suitable but the most indicative variables could differ relative to the ethnic population concerned.     

Positive “Water Test”—An External Indicator of Base of Skull Hinge‐Ring Fracture

Abstract: Despite having significant internal injuries, victims of motor vehicle accidents may have surprisingly few external manifestations of trauma. The water test describes a technique whereby water placed in an upwardly facing ear results in drainage from the nose and opposite ear, thus demonstrating transcranial passage of water. This sign can be demonstrated in cases of blunt cranial trauma where there is a “hinge” fracture involving the petrous temporal bones bilaterally associated with a ring fracture extending around the foramen magnum posteriorly. Such a fracture results in separation of the posterior and middle cranial fossae providing a track for water to traverse. The water test provides a quick and noninvasive method for demonstrating the presence of a particular type of skull fracture.     

Comparison Among Manual Facial Approximations Conducted by Two Methodological Approaches of Face Prediction

This study verified the difference between two methods of forensic facial approximation (FFA) regarding recognition and resemblance rates. Three‐dimensional models of skulls were obtained from computerized tomography (CT) scans of two subjects (targets). Two manual FFAs were performed for each target, by applying two different guidelines for the facial structures (what we called “American method” (AM) and “Combined method” (CM)). Unfamiliar assessors evaluated the sculptures by recognition and resemblance tests. The AM was that which allowed more correct responses of recognition and higher resemblance's scores for the male target (p < 0.001). Regarding guidelines for modeling characteristics of the face, the ones that are practical and easily performed for sculptures, such as the length of the anterior nasal spine multiplied by 3 for nose prediction, may offer better results in terms of resemblance.     

Classification of Porcine Cranial Fracture Patterns Using a Fracture Printing Interface,,

Distinguishing between accidental and abusive head trauma in children can be difficult, as there is a lack of baseline data for pediatric cranial fracture patterns. A porcine head model has recently been developed and utilized in a series of studies to investigate the effects of impact energy level, surface type, and constraint condition on cranial fracture patterns. In the current study, an automated pattern recognition method, or a fracture printing interface (FPI), was developed to classify cranial fracture patterns that were associated with different impact scenarios documented in previous experiments. The FPI accurately predicted the energy level when the impact surface type was rigid. Additionally, the FPI was exceedingly successful in determining fractures caused by skulls being dropped with a high‐level energy (97% accuracy). The FPI, currently developed on the porcine data, may in the future be transformed to the task of cranial fracture pattern classification for human infant skulls.     

A Biomechanical Evaluation of Skull–Brain Surrogates to Blunt High‐Rate Impacts to Postmortem Human Subjects

The field of forensic injury biomechanics is an emerging field. Biomechanically validated tools may assist interdisciplinary teams of investigators in assessing mechanisms of blunt head trauma resulting in skull fractures. The objective of this study is to assess the biofidelity of spherical, frangible skull–brain (SB) surrogates. Blunt impacts were conducted at 20 m/s, using an instrumented 103 g rigid impactor, to the temporo‐parietal region of four defleshed cephalic postmortem human subjects (PMHS). Force–deformation response, fracture tolerance, and fracture patterns were recorded for comparison to spherical skull–brain surrogates. Three brain substitutes were assessed: 10% gelatin, lead shot with Styrofoam and water. Force–deformation response of the skull–brain surrogates was similar to defleshed PMHS up to the point of fracture; however, none of the surrogates fractured at tolerance levels comparable to the PMHS. Fracture patterns of the skull–brain surrogates were linear and radiating, while PMHS fractures were all depressed, comminuted.     

Examination of misconceptions surrounding fatal fire victims

Fire deaths are not unusual in forensic investigative practice but due to the destructive nature of fire they are often very difficult to investigate. With the need to identify the deceased and the events surrounding the manner and cause of death, knowledge of thermally induced alteration to the human body is important. Within the fire investigation community, a number of misconceptions have been present for years regarding the protrusion of the tongue as an indicator of life during the fire, and fractured skulls as the result of brains boiling and skulls exploding. This work presents qualitative analysis on the experimental burning of 42 unembalmed human donated cadavers by the San Luis Obispo Strike Team (SLOFIST) on their annual Forensic Fire Death Investigation Course (FFDIC) between 2017 and 2019. Prior to burning, the position of the tongue within the dental arch was confirmed and sharp, blunt, surgical and gunshot trauma to the cranium documented. Temperature was recorded from ignition through to suppression with thermocouples present both within the scene and the body. Post burn analysis on the position of the tongue, observation of cranial fractures and presence of brain tissue were recorded and analysed in conjunction with thermocouple data, fire scene dynamics and body demographics. The results provide a more comprehensive understanding of the thermal environmental factors involved in producing the phenomena that facilitate these misconceptions, identifying that a more thorough understanding of individual fire scenes and their development is essential when interpreting alteration and injury to the body of the fatal fire victim.