骨盆损伤鉴定的影像学检查方法选择探讨

目的通过研究骨盆结构和常用影像学检查方法,对骨盆损伤的影像学检查方法的选择提出建议。方法研究数例法医学鉴定中骨盆损伤的案例,结合骨盆环的生物力学和骨盆损伤分型,并对X线透视、X线摄片检查、CT等检查方法进行比较。结果四个骨盆损伤案例都是多发损伤,通过X线和CT检查均能满意地确认。结论结合骨盆致伤方式和生物力学,注意被鉴定人是否存在多发伤,来选择适合的影像学检查方法以正确评价骨盆损伤。     

Classification of Pelvic Ring Fractures in Skeletonized Human Remains

Pelvic ring fractures are associated with high rates of mortality and thus can provide key information about circumstances surrounding death. These injuries can be particularly informative in skeletonized remains, yet difficult to diagnose and interpret. This study adapted a clinical system of classifying pelvic ring fractures according to their resultant degree of pelvic stability for application to gross human skeletal remains. The modified Tile criteria were applied to the skeletal remains of 22 individuals from the Cleveland Museum of Natural History and Universidad Nacional Autónoma de México that displayed evidence of pelvic injury. Because these categories are tied directly to clinical assessments concerning the severity and treatment of injuries, this approach can aid in the identification of manner and cause of death, as well as interpretations of possible mechanisms of injury, such as those typical in car-to-pedestrian and motor vehicle accidents.     

Posttraumatic acute cholecystitis. Relationship to the initial trauma

Posttraumatic acute cholecystitis is an often unrecognized and potentially fatal complication seen among patients hospitalized for trauma, and differs in etiology from cholecystitis which develops de novo. The cause, although not yet clearly defined, is believed to be related to bile stasis, ischemia, bacterial infection, sepsis, the activation of factor XII, and the Shwarzman reaction. A case is described in which a 53-year-old man with pelvic fractures developed acute acalculous cholecystitis and died of multiple organ failure 3 weeks following cholecystectomy. The histopathological findings are also reported; these are most likely attributed to the Shwarzman reaction or the activation of the factor XII pathways. There has been a tendency to regard posttraumatic acute acalculous cholecystitis as induced by trauma, and calculous as mere coincidence. We believe, however, that it is not calculous but histopathological findings that determine whether acute cholecystitis following trauma was more than coincidence or just mere coincidence. Although progress in clinical care has improved the chances of survival of severely traumatized patients, posttraumatic acute cholecystitis has been increasing in frequency. We cannot be careful enough in judging the relationship of this fatal complication to the initial trauma.     

Forensic Epidemiologic and Biomechanical Analysis of a Pelvic Cavity Blowout Injury Associated with Ejection from a Personal Watercraft (Jet‐Ski)

Jet‐propelled personal watercraft (PWC) or jet‐skis have become increasingly popular. The means of propulsion of PWC, which is a jet of water forced out of small nozzle at the rear of the craft, combined with a high risk of falling off of the seat and into close proximity with the water jet stream, raise the potential for a unique type of injury mechanism. The most serious injuries associated with PWC falls are those that occur when the perineum passes in close proximity to the jet nozzle and the high‐pressure water stream enters the vaginal or rectal orifice. We describe the forensic investigation into a case of an anovaginal “blowout” injury in a passenger who was ejected from the rear seat position of a PWC and subsequently suffered life‐threatening injuries to the pelvic organs. The investigation included a biomechanical analysis of the injury mechanism, a summary of prior published reports of internal pelvic injuries resulting from PWC falls as well as other water sports and activities, and a comparison of the severity of the injuries resulting from differing mechanisms using the New Injury Severity Score (NISS). The mean (±standard deviation [SD]) NISS values for reported PWC injuries [not including the NISS of 38 in this case study] were 11.2 (±9.5), while the mean value for reported water‐skiing falls was half that of the PWC group at 5.6 (±5.2). It was concluded that the analyzed injuries were unique to a PWC ejection versus other previously described non‐PWC‐associated water sport injuries. It is recommended that PWC manufacturers help consumers understand the potential risks to passengers with highly visible warnings and reduce injury risk with revised seat design, and/or passenger seat “deadman” switches.     

Fatal intoxication due to tramadol alone: case report and review of the literature

Poisoning may also lead to both coma and multiple organ failure, also in youngsters without a known major medical history. As not all toxic agents are routinely screened when a poisoning is suspected, it is useful to consider less frequently encountered poisons in certain cases. We describe the occurrence of asystole and multiple organ failure which occurred in a young man after a suspected tramadol overdose. The tramadol concentration on admission in the ICU was indeed 8 microg/ml (mg/l), far above the therapeutic range. Subsequently, the patient developed severe acute liver failure, finally leading to death. Post-mortem toxicology did not reveal any other poison responsible for this unfavourable course as only very high serum and tissue tramadol and desmethyltramadol concentrations were found. Only a few fatal poisonings attributable to tramadol alone, as observed in our case, have been reported. An overview of these cases is presented.     

Characterization and Comparison of Injuries Caused by Accidental and Non‐accidental Blunt Force Trauma in Dogs and Cats

Motor vehicle accidents (MVA) are often difficult to distinguish from non‐accidental injury (NAI). This retrospective case–control study compared animals with known MVA trauma against those with known NAI. Medical records of 426 dogs and cats treated after MVA and 50 after NAI were evaluated. Injuries significantly associated with MVA were pelvic fractures, pneumothorax, pulmonary contusion, abrasions, and degloving wounds. Injuries associated with NAI were fractures of the skull, teeth, vertebrae, and ribs, scleral hemorrhage, damage to claws, and evidence of older fractures. Odds ratios are reported for these injuries. MVA rib fractures were found to occur in clusters on one side of the body, with cranial ribs more likely to fracture, while NAI rib fractures were found to occur bilaterally with no cranial–caudal pattern. Establishing evidence‐based patterns of injury may help clinicians differentiate causes of trauma and may aid in the documentation and prosecution of animal abuse.     

Analysis of the incidence of pelvic trauma in fatal automobile accidents

Pelvic fractures are frequent complications of motor vehicle accidents, and motor vehicle accidents are the most common cause of pelvic fracture. Although pelvic fractures are associated with considerable morbidity and mortality, there has traditionally been no attempt to grade or classify pelvic fractures during postmortem examination. The authors performed a retrospective study of cases examined at the Jefferson County Coroner/Medical Examiner Office from 1994 to 1996, reviewing investigative reports and autopsy findings. Radiographs were examined for the presence and Tile type of pelvic fracture. Pelvic fractures were identified in 88 of 392 cases (23%). In most (89%), the pelvic fracture was readily classified according to Tile type on the basis of radiographs and the inferred mechanism of injury. This study indicates that current estimates of the mortality of pelvic fractures are low because of the exclusion of individuals who do not survive to hospitalization. Furthermore, pelvic fractures in rapidly fatal motor vehicle accidents tend to be more severe than fractures in individuals who have a significant interval of survival. The presence and classification of pelvic fractures may be readily determined by radiographs in most cases. The Tile classification scheme is easy to apply and has important implications in the comparison of study groups.     

Identification of the driver in two-rider motorcycle accidents. Inguinal contusion-laceration as an indication of the driver

In motorcycle accidents involving two riders, medicolegal identification of the driver is necessary when one or both riders die. It is particularly important in the latter case, because the survivor almost always insists that he or she was not driving. One characteristic injury that distinguishes the driver from the passenger is inguinal contusion-laceration (accompanied internally by pelvic fracture). This injury, caused by collision of the pelvis with the fuel tank, identifies the driver.     

应用Young-Burgess分型推断交通事故受伤人员骨盆损伤机制

目的根据骨盆骨折X线片Young-Burgess分型推断道路交通事故致死者（roadtrafficfatalities,RTFs）骨盆损伤机制,并探讨其法医学应用价值。方法回顾性分析128例车外成人RTFs尸体骨盆X线片的Young-Burgess分型,根据分型推断骨盆损伤机制,对照真实案情进行统计分析。结果可区分APC、LC亚型的推断骨盆损伤机制正确率（94.1%、92.9%）明显高于不区分亚型的（63.6%、70.7%）（P〈0.05）;区分LC亚型还能进一步推断后侧方、前侧方或是持续、较大的前侧方外力。结论综合各种影像手段区分Young-Burgess亚型可较好地推断骨盆损伤机制,为道路交通事故现场重建提供可靠依据。     

The sensitivity and specificity of control surface injuries in aircraft accident fatalities

Among the important determinations that aircraft crash investigators try to make is which occupant of an aircraft was attempting to control the aircraft at the time of the crash. The presence or absence of certain injuries of the extremities is used to help make this determination. These "control surface injuries" reportedly occur when crash forces are applied to a pilot's hands and feet through the aircraft's controls. We sought to clarify the significance of these injuries and the frequency with which their presence indicates that the decedent was the person that might have been trying to control the aircraft, questions that are frequently asked of the examining pathologist. We studied sequential fatalities of airplane and helicopter crashes in which autopsies were performed by the Office of the Armed Forces Medical Examiner, excluding those that were known to have been incapacitated before the crash and those that were known to have attempted to escape from the aircraft, collecting 100 "qualified" crash decedents. The incidence of control surface injuries was determined for both pilots and passengers. The sensitivity and specificity of control surface injuries were calculated by classifying the decedents into a 4-cell diagnostic matrix. The positive and negative predictive values for control surface injuries were also calculated. Injuries that met the published definitions of control surface injuries had high incidences in passengers, as well as pilots, giving the term control surface injury a diagnostically unacceptable sensitivity and specificity for indicating "a pilot attempting to control an aircraft." We offer caveats and refinements to the definition of these injuries that help to increase the sensitivity and specificity of this term.     

An Investigation into the Relationship between Human Cranial and Pelvic Sexual Dimorphism

When faced with commingled remains, it might be assumed that a more “masculine” pelvis is associated with a more “masculine” cranium, but this relationship has not been specifically tested. This study uses geometric morphometric analyses of pelvic and cranial landmarks to assess whether there is an intra‐individual relationship between the degrees of sexual expression in these two skeletal regions. Principal component and discriminant function scores were used to assess sexual dimorphism in 113 U.S. Black individuals. Correlation values and partial least squares regression (PLS) were used to evaluate intra‐individual relationships. Results indicate that the os coxae is more sexually dimorphic than the cranium, with element shape being more sexually dimorphic than size. PLS and correlation results suggest no significant intra‐individual relationship between pelvic and cranial sexual size or shape expression. Thus, in commingled situations, associations between these skeletal elements cannot be inferred based on degree of “masculinity.”     

Accidental potassium dichromate poisoning. Toxicokinetics of chromium by ICP-MS-CRC in biological fluids and in hair

Intoxications by chromium (Cr) compounds are very life threatening and often lethal. After oral ingestion of 2 or 3g of hexavalent Cr (Cr(VI)), gastrointestinal injury, but also hepatic and renal failure, often occurs which each leads to a fatal outcome in most patients. Cellular toxicity is associated with mitochondrial and lysosomal injury by biologically Cr(VI) reactive intermediates and reactive oxygen species. After Cr(VI) has been absorbed, there is not much that can be done except to control the main complications as the treatment is only symptomatic. The biotransformation of Cr(VI) to Cr(III) reduces the toxicity because the trivalent form does not cross cellular membranes as rapidly. In fact, more than 80% of Cr(VI) is cleared in urine as Cr(III). We report the case of a 58-year-old male patient who was admitted to hospital after accidental oral ingestion of a 30 g/L potassium dichromate (the estimated amount of ingested Cr is about 3g). ICP-MS equipped with a collision/reaction cell (CRC) and validated methods were used to monitor plasma (P), red blood cells (RBCs), urine (U) and hair chromium. For urine the results were expressed per gram of creatinine. After 7 days in the intensive care unit, the patient was discharged without renal or liver failure. P, RBC and U were monitored during 49 days. During this period Cr decreased respectively from 2088 μg/L to 5 μg/L, 631 μg/L to 129 μg/L and 3512 μg/g to 10 μg/g. The half-life was much shorter in P than in RBC as the poison was more quickly cleared from the P than from the RBC, suggesting a cellular trapping of the metal. Hair was collected 2 months after the intoxication. We report a very rare case of survival after accidental Cr poisoning which has an extremely poor prognosis and usually leads to rapid death. For the first time, this toxicokinetic study highlights a sequestration of chromium in the RBC and probably in all the cells.     

Psychological Injuries and Legal Decision Making in Civil Cases: What We Know and What We Do not Know

Civil plaintiffs frequently seek monetary compensation for their psychological injuries. Despite the increased study of psychological injury within the legal system, there has been little empirical examination of how psychological injury evidence impacts legal decisions. To illuminate what is known (and not known) on this topic, this paper reviews legal and empirical research regarding how legal decision makers (judges and jurors) perceive and use psychological injury evidence to render civil judgments. A few themes emerged from this review: (1) Courts generally devalue psychological injury, often making it difficult for plaintiffs to pursue and succeed on these claims; (2) these difficulties are a likely byproduct of legal decision-makers’ misperceptions of mental illness; and (3) despite a recent surge in empirical research on how jurors perceive and use psychological injury evidence to render civil decisions, many unexplored areas remain. Specific recommendations for legal policy and suggestions for future research are highlighted throughout this review.     

Identification and determination of age of needle tracks in human skin (author's transl)]

Examination of enzymic activities and histochemical reactions on needle pricks can be used to determine the age of micro-injuries with sufficient exactness. Well preserved skin shows patterns of enzymes which also appear with other skin injuries and which were described in detail especially by Raekallio (1970, 1972). In autolytical changes of the skin the adenosinetriphosphatase-reaction is still reliable and can be successfully estimated. If one has sufficient experience it is possible to fairly exactly estimate the age of an injury within the first hour after the injury by preparation of the adenosinetriphosphatase-reaction. If the times of injections are known one frequently succeeds in determining the time of death by exactly determining the age of the injury. In legal expertises the histochemical reactions can rightly be regarded as useful indications of a certain age of the injury. But they do not allow an exact estimate "beyond a reasonable doubt".     

A biomechanical analysis of the causes of traumatic brain injury in infants and children

There is significant disagreement among medical professionals regarding the mechanisms for infant brain injury. This disagreement is due in part to the failure by some to acknowledge and incorporate known biomechanical data and models into hypotheses regarding causes. A proper biomechanical understanding of the mechanisms of traumatic brain injury (TBI) challenges many published and testified assumptions regarding TBI in infants and children. This paper analyzes the biomechanical relationship between the causes of TBI in infants and children, and their physiological consequences. Loading characteristics, injury parameters and criteria, scaling, failure characteristics, differences between infants and adults, and impact due to falls are described and discussed in the context of the laws of mechanics. Recent studies are critiqued with reference to their contribution to an understanding of brain injury mechanisms. Finally, methods for improving our currently incomplete knowledge of infant head injuries, and their mechanisms, consequences and tolerances are proposed. There is an urgent need for close collaboration between physicians and biomechanicians to objectively and scientifically evaluate infant head injuries to further define their mechanical bases, and to assist in their diagnosis and treatment.     

Metastatic calcification of the cardiac conduction system with heart block: an under-reported entity in chronic renal failure patients

Systemic metastatic calcification is a common complication of chronic renal failure. Cardiac involvement is particularly ominous, especially when the cardiac conduction system is affected. Conduction defects, arrhythmias, and sudden death have all been reported with conduction system calcification; however, these are relatively under-reported or unrecognized causes of cardiac morbidity and mortality. We describe a 40-year-old man with Von Hippel-Lindau disease who had been maintained on hemodialysis for two years following bilateral nephrectomies for renal cell carcinoma. The patient presented with symptomatic complete heart block that had progressed from Mobitz type I atrioventricular block. Two months later, while being internally paced, the patient died unexpectedly after a complicated hospital admission. Postmortem revealed extensive vascular, myocardial, and conduction system calcification. Conduction system calcification may cause sudden death in chronic renal failure patients during hospital admission, or unexpectedly while the patient is in the community. Knowledge of this condition is necessary to detect it, as the conduction system is not routinely examined. A routine abbreviated conduction system examination is warranted for patients with systemic metastatic calcification, especially if they have sudden death or a known history of heart block.     

Injury Pattern as an Indication of Seat Belt Failure in Ejected Vehicle Occupants

Prior authors have suggested that when occupant ejection occurs in association with a seat belt failure, entanglement of the outboard upper extremity (OUE) with the retracting shoulder belt will invariably occur, leaving injury pattern evidence of belt use. In the present investigation, the authors assessed this theory using data accessed from the NASS‐CDS for ejected front seat occupants of passenger vehicles. Logistic regression models were used to assess the associations between seat belt failure status and injuries. Injury types associated with seat belt failure were significant OUE and head injuries (OR = 3.87, [95% CI 1.2, 13.0] and 3.1, [95% CI 1.0, 9.7], respectively). The two injury types were found to be a predictor of seat belt use and subsequent failure only if combined with a high (≥0.8) precrash probability of belt use. The injury pattern associated with a seat belt failure‐related ejection has limited use in the forensic investigation of crash‐related ejections.     

Metric analysis of sex differences in South African black and white pelves

Sex determination of unknown skeletal material is one of the most vital determinations made by forensic anthropologists. Numerous studies have focussed on the differences, both osteometric and morphological, between the sexes of a particular racial phenotype and population. Previous work by a variety of researchers has underscored the necessity of population specific standards. The purpose of this research is to metrically assess sex differences in the pelvis of South African whites and blacks and develop standards tailored to these groups. Data were collected from 400 known sex/race skeletons from the Pretoria and Dart Collections. Nine measurements (traditional and newly developed) were taken and subjected to SPSS stepwise and direct discriminant analysis. Results indicated that there are significant differences (p < or = 0.001) between the sexes of both races for most measurements. Discriminant function analysis selected ischial length as the most sexually dimorphic dimension in whites (averaged 86% accuracy), while acetabulum diameter was most diagnostic in blacks (averaged 84% accuracy). Six functions were developed from the pelvic dimensions. Highest accuracy was achieved from Function 1 (including all dimensions) which averaged 95.5% correct classification in whites and 94% in blacks. Functions based on selected parts of the pelvis were not as effective and ranged from 73-86% in whites and 72-84% in blacks. This research provided evidence of the significant sex differences that exist between the pelves of South African whites and blacks whilst measurements used here for discriminant function analysis gave classifications with high accuracies. These results can be used to aid in the identification of human skeletal remains in South Africa.     

Alcohol intoxication may exacerbate the effects of blunt cranial trauma through changes in brain free magnesium levels

Moderate to high levels of alcohol decrease brain intracellular free magnesium concentration, a factor known to be critical in brain injury. Phosphorus magnetic resonance spectroscopy was used to examine changes to brain free magnesium concentration after blunt cranial trauma in alcohol-intoxicated rats. Rats exposed acutely or chronically to alcohol sufficient to increase blood alcohol levels to between 150 and 350 mg/dL demonstrated a brain free magnesium level that was 20-50% less than in nonintoxicated animals (p < 0.01). After injury, brain free magnesium levels declined more rapidly and to a greater extent in alcohol-affected animals than in nonintoxicated control animals (p < 0.001). As both preinjury depletion of magnesium and degree of magnesium decline after brain injury have been associated with poor recovery, these findings suggest that moderate to severe alcohol intoxication may predispose the brain to a worse outcome by reducing brain free magnesium levels, both before and after injury.     

Investigation of cardiac troponins in postmortem subjects: comparing antemortem and postmortem levels

The limitations of autopsy in the diagnosis of death due to ischemic heart disease are well known. In the living, a simple reliable biochemical assay for cardiac troponins is used in the diagnosis of acute myocardial ischemia. Several studies have investigated the use of biochemical assays for cardiac troponins in postmortem subjects as a means to distinguish between a cardiac and anoncardiac cause of death. All of these studies, however, rely upon assigning subjects to "cardiac" or "noncardiac" death on the basis of a postmortem examination. As postmortem examination does not always accurately distinguish between these two groups, this approach is intrinsically flawed.Our study compares antemortem and postmortem cardiac troponin levels in five subjects. The antemortem samples were retrieved from the hospital biochemistry laboratory after each subject's death. The postmortem samples for each subject were taken from different sites and at different times during the early postmortem period.Erratic results bearing little or no relation to the antemortem cardiac troponin level were obtained for all subjects. Four of the five subjects had raised antemortem troponin levels, although only one had a cardiac cause of death.From this, we conclude that postmortem blood is not a suitable substrate for standard biochemical assays of cardiac troponins, which are designed for use on serum taken from living patients. In addition, the results of our study support the view that elevated cardiac troponins are a marker of serious morbidity and are not specific for cardiac injury as the primary cause of morbidity or mortality.