A validation study for duct tape end matches

Fracture matches are considered to be the strongest association achievable in forensic examinations of glass, metal, wood, plastic, paint, tape, and other trace evidence. Despite being fairly routine examinations, few publications exist to support their admissibility in court. This study was designed, using duct tape as the fractured medium, to determine the validity and error rate associated with conducting end match (fracture match) examinations on this material. Five test designs, which varied either the source roll of tape or manner of separation (torn or cut) from the roll, were administered to four analysts with instructions to examine the assigned test sets for end matches. If an end match was not identified by the initial analyst, the entire test set was independently evaluated by the remaining three analysts. Results indicated that while tape grade did not hinder end match identification, the manner of separation could affect results.     

Digital analysis of experimental human bitemarks: application of two new methods

Bitemark determination in forensic odontology is commonly performed by comparing the morphology of the dentition of the suspect with life-sized photographs of injury on the victim's skin using transparent overlays or computers. The purpose of this study is to investigate the suitability of two new different methods for identification of bitemarks by digital analysis. A sample of 50 volunteers was asked to make experimental bitemarks on the arms of each other. Stone study casts were prepared from upper and lower dental arches of each volunteer. The bitemarks and the study casts were photographed; the photos were entered into the computer and Adobe Photoshop software program was applied to analyze the results. Two methods (2D polyline and Painting) of identification were used. In the 2D polyline method, fixed points were chosen on the tips of the canines and a straight line was drawn between the two fixed points in the arch (intercanine line). Straight lines passing between the incisal edges of the incisors were drawn vertically on the intercanine line; the lines and angles created were calculated. In the painting method, identification was based on canine-to-canine distance, tooth width and the thickness, and rotational value of each tooth. The results showed that both methods were applicable. However, the 2D polyline method was more convenient to use and gave prompt computer-read results, whereas the painting method depended on the visual reading of the operator.     

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。     

生理性小骨骺分离的影像学观察及其与骨端骨折的鉴别研究

目的探讨生理性小骨骺分离的影像学特征及其与骨端撕脱性小骨折片的鉴别方法。方法回顾性分析21例怀疑骨端骨折而行法医学鉴定的案例,通过观察骨端游离小骨周边是否存在连续的骨皮质、小骨片相对侧表面是否有连续的骨皮质和局部软组织肿胀情况,并结合损伤机理考察骨折形态。结果21个案例中,6例游离小骨片与相对侧骨表面呈锐利的骨折线,并缺乏连续的骨皮质,周边可见软组织肿胀,考虑骨端撕脱小骨折;15例游离小骨与相对侧骨表面存在连续性骨皮质,考虑为骨关节端永存分离性小骨骺。观察游离小骨周边和相对侧骨表面是否有骨皮质,高分辨CT可以获得满意的结果;观察小骨周边相应的软组织肿胀,MRI较好。结论通过对骨端游离小骨详细的影像学观察,有助于鉴别骨折与生理性小骨骺分离。     

眼眶骨折的影像学诊断及法医学评定

在眼眶骨折的法医学鉴定中常常出现漏诊和误诊。目前影像学技术在研究眼眶骨折的法医学特点和评价外伤的严重程度中有重要的意义。本文综述了眼眶骨折的分类、发病机制和影像学诊断的特点,对于眼眶骨折的法医学评价和鉴定有较好的帮助。     

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.     

Fracture Characteristics of Entrapped Head Impacts Versus Controlled Head Drops in Infant Porcine Specimens,,

In many forensic cases, the job of forensic pathologists and anthropologists is to determine whether pediatric death is due to an abusive act or an accidental fall. The goal of this study was to compare the cranial fracture patterns generated on the parietal bone of a developing, infant porcine (pig, Sus scrofa) model by a controlled energy head drop onto a plate versus previous data generated by blunt force impact at the same energy onto the head constrained to a plate. The results showed that blunt force impacts on a head constrained to a rigid plate produces more fracture, but the same general pattern, as that for a head dropped onto the plate with the same level of impact energy. The study suggests that head constraint may be an important factor to consider in the evaluation of death causation for blunt force impacts to the pediatric skull.     

手法复位小夹板固定配合接骨续筋汤治疗老年骨质疏松性Colles骨折临床观察

目的 观察手法复位小夹板固定配合接骨续筋汤治疗老年骨质疏松性Colles骨折的临床疗效。方法 将68例老年骨质疏松性Colles骨折患者随机分为治疗组和对照组,每组34例。两组患者均接受手法复位小夹板固定治疗,并给予常规治疗,治疗组在此基础上内服接骨续筋汤治疗。观察并记录两组患者治疗前,治疗1、2周后视觉模拟评分（visual analogue scale,VAS）,患侧肿胀情况,治疗4、8周后骨折愈合X线评分,并记录骨折愈合时间;骨折愈合后采用Garland-Werley评分对腕关节的活动功能进行评价;治疗90 d后,对两组患者的临床疗效进行评价。结果 治疗1、2周后,两组VAS评分及患侧肿胀度均较治疗前明显降低（P<0.05）,且治疗组VAS评分和患侧肿胀度均明显低于对照组（P＜0.05）。治疗8周后,两组骨折愈合X线评分均较治疗4周后显著上升（P＜0.05）,且治疗组骨折愈合X线评分明显高于对照组（P＜0.05）。与对照组比较,治疗组骨折愈合时间显著缩短（P＜0.05）,Garland-Werley评分显著降低（P＜0.05）。治疗90 d后,两组临床疗效的差异有统计学意义（P＜0.05）,治疗组临床疗效优于对照组。结论 在手法复位小夹板固定基础上服用接骨续筋汤可提高老年骨质疏松性Colles骨折的疗效,能有效缓解患者骨折后疼痛、肿胀程度,缩短骨折愈合时间,改善腕关节活动功能。