普通正三轮摩托车转向前叉断裂原因分析

通过对一辆导致了事故的普通正三轮摩托车转向前叉左侧减震器筒与其底座焊接部位的断裂原因进行分析。经过对断口宏观形貌、微观形貌的观察,以及对断裂部位材质、金相组织的检验分析,判断转向前叉的断裂为沿焊接结合面发生的沿晶韧窝断裂,是因焊接工艺不合理引起的。     

热处理方法恢复PVC胶带分离缘形态

目的建立一种能有效恢复PVC胶带上变形分离缘原始形态的热处理方法。方法选取3个品牌的PVC胶带作为实验样品,沿宽度方向进行不同程度的拉伸,用水浴加热的方法对变形的分离缘进行处理,通过实验确定加热温度、时间以及对变形的恢复效果。结果基于分离缘宽度测量的变形程度大大缩小,对分离缘的凹凸形态恢复效果良好。结论本文建立的热处理方法,能有效地对PVC胶带上变形的分离缘进行形态恢复,可大大增加整体分离痕迹检验的可行性、结论的准确性及说服力。     

螺旋CT三维重建在肋骨骨折法医临床鉴定中的应用

目的探讨螺旋CT三维重建评价肋骨骨折在法医临床中应用价值。方法收集肋骨骨折35例,分别采用X线摄片、CT扫描及螺旋CT三维重建检查。结论35例检查都取得清晰的立体图像,且可以消除周围组织结构,单独观察肋骨骨折情况。结果:螺旋CT三维重建在肋骨骨折的诊断、法医临床学中有较高的价值。     

86例鼻部复合性骨折的法医鉴定

目的探讨鼻部复合性骨折的认定、分型和损伤程度的法医学鉴定。方法对86例鼻部复合性骨折鼻骨CT片(轴扫 冠扫)和有关病历资料进行观察分析。结果将86例伤者按骨折种类分成鼻骨并发鼻部非鼻骨骨折(81例)和鼻部非鼻骨复合性骨折(5例)两类,然后再进一步细分。结论86例伤者中轻伤80例(93%),轻微伤6例(7%)。鼻部复合性骨折的损伤程度评定关键在于应按照《人体轻微伤的鉴定》(GA/T146-1996)和《人体轻伤的鉴定(试行)》的有关规定或标准认定和分型,这样鉴定结论才会准确可靠。     

246例高坠案件中坠落高度与损伤分析

目的对高坠案件进行统计分析,为相关鉴定研究提供参考。方法收集上海市浦东地区最近十年来记录有坠落距离的246例高坠案件,对人体损伤的特点进行比较分析。结果自杀高坠的高度显著高于意外高坠的高度(25.70m:13.98m);所有高坠中,头部损伤概率较高(75.2%),颈部损伤概率较低(6.5%);意外高坠的头部损伤概率高于自杀组(89.4%:75.2%)。结论意外高坠的死者比自杀高坠的死者更缺乏四肢对于头部的保护;过低的颈部损伤发现率提示国内法医工作者应该更加重视在高坠案件中的对于颈部损伤的检查。     

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.     

Chronic Alcohol Abuse Leads to Low Bone Mass with No General Loss of Bone Structure or Bone Mechanical Strength,

Chronic alcohol abuse (CAA) has deleterious effects on skeletal health. This study examined the impact of CAA on bone with regard to bone density, structure, and strength. Bone specimens from 42 individuals with CAA and 42 individuals without alcohol abuse were obtained at autopsy. Dual‐energy X‐ray absorptiometry (DEXA), compression testing, ashing, and bone histomorphometry were performed. Individuals with CAA had significantly lower bone mineral density (BMD) in the femoral neck and significantly lower bone volume demonstrated by thinner trabeculae, decreased extent of osteoid surfaces, and lower mean wall thickness of trabecular osteons compared to individuals without alcohol abuse. No significant difference was found for bone strength and structure. Conclusion: CAA leads to low bone mass due to a decrease in bone formation but with no destruction of bone architecture nor a decrease in bone strength. It is questionable whether this per se increases fracture risk.     

X线数字图像法推断前臂骨折形成时间

目的利用X线数字图像法推断前臂骨折形成的时间。方法收集70例前臂骨折患者随访的620张X线数字图像,根据X线检查骨折愈合评判标准列表,将骨折愈合过程分为5级,利用Photoshop的图像处理和测量功能,对不同年龄组、不同治疗方式的患者骨折愈合过程相关放射学标志进行观察和测量,运用SPSS11.5软件对各级愈合时间进行分析。结果年龄和手术与否分别是影响骨折愈合的独立因素,根据不同年龄、不同治疗方式可以得到各级愈合时间列表。以愈合Ⅲ级的出现时间为例,青年组采用石膏固定治疗的,平均时间为12.2周,采用手术治疗的,需要18周,而少年组采用石膏固定治疗的,则只需5.8周。结论根据骨折愈合过程中X线数字图像指标,对患者进行分组观察,可提高推断骨折形成时间的准确度。     

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.     

Early Signs of Fracture Repair in the Human Rib Cage: Implications for Forensic Casework

The decomposed body of a woman discovered beneath a collapsed structure was examined at the C.A. Pound Human Identification Laboratory. Despite a mix of rib fractures with and without indications of healing, it is most likely that all fractures occurred as a result of a single, compressive event. Signs of intramembranous, and possibly direct, fracture healing at the incomplete fractures without signs of endochondral ossification at the complete fractures suggest the individual died very shortly—but not immediately—after injury. Given the case circumstances, the findings inform immediate cause of death. This case study highlights that differential healing as a result of a single event is possible. Further, it illustrates the importance of careful examination of micro‐discontinuities/cracks that can occur in association with major fractures. Fracture healing and dating data are discussed, as is the possible need for critical evaluation of the antemortem/perimortem boundary.