A rabbit model of graded primary mechanical injury to brainstem / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To introduce a new animal model of graded mechanical primary brainstem injury (BSI).</p><p><b>METHODS</b>Altogether 45 rabbits were subjected to BSI by type II biological impact machine designed by the Third Military Medical University. The animals were divided into 4 experimental groups (n equal to 10) and 1 control group (n equal to 5) according to different magnitudes of impact pressure imposed on the occipital nodule: Group 1, 500-520 kPa; Group 2, 520-540 kPa; Group 3, 540-560 kPa; Group 4, 560-580 kPa and Group 5, 0 kPa with 20 kPa increase in each grade. The impact depth was a constant 0.5 cm. After injury, the clinical symptoms and signs as well as pathological changes were observed.</p><p><b>RESULTS</b>Rabbits in Group 1 revealed mild physiological reaction of BSI. They had localized cerebral contusion with punctate hemorrhage and subarachnoid hemorrhage (SAH) was limited to the peripheral tissues at the impact area. In Group 2, obvious physiological reaction was observed. Local pathological lesions reached the superficial layer of brainstem tissues; focal hemorrhage and girdle-shaped SAH in basilar pon were observed under microscope. In Group 3, BSI was more severe with a long respiratory depression. Pathological lesions reached the inner portion of brainstem with massive hemorrhage and the whole brainstem was wrapped by subarachnoid hematoma. In Group 4, most rabbits died due to severe BSI. Pathological lesions deepened to the central brainstem with wide pathological change, rapture of the medulla oblongata central canal. Group 5 was the control group, with normal brainstem structure and no lesion observed.</p><p><b>CONCLUSION</b>This model successfully simulates different levels of brainstem mechanical injury and clearly shows the subsequent pathological changes following injury. It takes two external parameters (impact pressure and depth) and has a similar injury mechanism to clinical accelerating BSI. Moreover it is reproducible and stable, thus being be- neficial for exploring pathophysiological mechanism, diagnosis and forensic identification of various degrees of BSI.</p>

Forensic medical study on morphology and formative mechanism of blunt head injury / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To study the patterns and morphologic characteristics of blunt head injury and analyse its formative mechanism in attempt to provide references for medicolegal expertise.</p><p><b>METHODS</b>The statistical analysis was done in terms of gender, age, as well as the nature, pattern, location, and feature of the injuries.</p><p><b>RESULTS</b>Among the 202 cases of head injury-induced death, 124 were male and 78 female with the age ranging from 1-81 years. Death caused by homicide was dominant (106, 52.5%), followed by suicide (49, 24.3%) and accident (44, 21.8%). The majority of suicide-induced death were by falling from height, and traffic crash was responsible for majority of unexpected death cases. The morphology and pathogenesis of the injuries varied according to differences on the mode, magnitude, and orientation of the outside force giving rise to blunt injury as well as the character of vulnerants.</p><p><b>CONCLUSION</b>Studies on the morphology and its formative rationale of blunt head injury will offer easy access to medicolegal expertise on the mode and character of the injury.</p>

Morphologic studies of high fall injuries / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>By studying the mode and morphologic character of high fall injuries on the scene, and exploring the injury situation of different heights, different fall ways and postures, to provide a reference for the forensic identification of high fall injury.</p><p><b>METHODS</b>All the high fall cases were statistically analysed according to their gender, age, ground-touching posture, fall height, site and type of the injury.</p><p><b>RESULTS</b>Among 134 high fall cases, 98 were male and 36 were female with the age ranging from 2-71 years (37.6+/-16.9 on average), in which, 10-60 years old group consisted of 110 cases (82%). Most cases fell from windows or roofs (73%) and the touching objects were cement ground or shaft bottom of elevators. Among these cases, head injury was generally serious, followed by chest and abdominal injuries. The morphologic changes depend upon the height, nature, as well as the posture at the point while the body touches the ground.</p><p><b>CONCLUSION</b>Morphologic study of high fall injury assists medicolegal physicians to make correct identifications of the cause and nature of high fall injuries.</p>

Analysis of 86 fatal motorcycle frontal crashes in Chongqing, China / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To analyze the injuries of motorcyclists involved in fatal motorcycle frontal crashes.</p><p><b>METHODS</b>A survey group involving multi-discipline experts was built to randomly collect data on fatal motorcycle frontal collision accidents that occurred in Chongqing during 2006-2010. The sampled information included medical or autopsy reports, blood alcohol concentration (BAC) level, helmet use, accident witness, field sketch as well as field photos. The motorcyclist injuries were scored according to the Abbreviated Injury Scale (AIS) 2005. The involved riders with a BAC level larger than or equal to 20 mg/ml were attributed to alcohol use. Data were processed statistically with nonparametric test via software SPSS 11.0.</p><p><b>RESULTS</b>A total of 86 fatal motorcycle frontal crashes were sampled and further analyzed. The age of motorcyclists enrolled in this investigation showed nominal distribution and the middle-aged (30-39 years) occupied the highest percentage of fatalities. There were only 14 motorcyclists (16.3%) wearing helmets at the moment of collision. And 12.8% of these motorcyclist crashes were attributable to alcohol use. Impact injury was the main fatal cause, accounting for 72% of motorcyclist deaths, followed by tumbling injury (26%) and run-over (2%). Respectively 84%, 22% and 19% of motorcyclists who sustained head, chest and abdominal trauma died. Extremity injury was the most frequently observed injury type.</p><p><b>CONCLUSIONS</b>This investigation is helpful to build accident prevention programs and develop protection devices which may effectively mitigate injuries and prevent deaths following motorcycle frontal collision accidents. Further investigations on motorcycle collision accidents are still needed.</p>