Mario Darok

Pressure measurements in the spinal canal of post-mortem human subjects during rear-end impact and correlation of results to the neck injury criterion.

The aim of this study is to validate the pressure effect theory on human beings during a realistic rear-end impact and to correlate the neck injury criterion to pressure in the spinal canal. Sled experiments were performed using a test setup similar to real rear-end collisions. Test conditions were chosen based on accident statistics and recordings of real accidents. In particular, velocity change and acceleration level were reproduced similar to actual collisions. The head restraint as well as the seat back were adjusted to different positions. Two small pressure transducer were implemented to the spinal canal of postmortem human subjects and pressure measurement similar to the pig experiments (using exactly the same equipment) were performed. A total set of 21 experiments with four different subjects were performed. The subjects were additionally instrumented with triaxial accelerometers that allowed for calculation of the NIC criterion. Results showed that NIC and pressure amplitudes of the CSF correlate well and therefore NIC seems to be able to predict these amplitudes also for human beings. Conclusions whether these pressure effects induce soft tissue neck injuries or not could not be drawn and should be investigated in further research.

Massive injury to the heart after attempted active compression-decompression cardiopulmonary resuscitation

An 84-year-old woman was unsuccessfully resuscitated for 3 min using standard cardiopulmonary resuscitation (CPR), followed by 15 min of active compression-decompression (ACD). The autopsy revealed that death was due to myocardial infarction complicated by rupture of the infarcted area and pericardial tamponade was diagnosed. Furthermore, a series of rib fractures, a transverse fracture of the sternum, rupture of the pericardial sac, the right ventricle, both atria and lacerations of the ascending aorta, were found with no signs of a vital reaction. To our knowledge, such extensive cardiac injury after CPR has not been previously reported. It is suggested that the pre-existing pericardial tamponade, the age of the patient and the application of the ACD-device to incorrect areas of the chest contributed to the extent of the cardiac injury. This case further adds to the suspicion of an increased risk of cardiac injuries when using an ACD device for cardiac massage.

Sudden death from myocardial contusion following an isolated blunt force trauma to the chest.

Abstract Cardiac contusion is a common concomitant injury in blunt, non-penetrating chest trauma and is mostly a benign disorder which remains undiagnosed. In the case presented, a young man sustained a single blunt trauma to the chest from falling pieces of a wooden wheel and died at the scene. Among other findings, the autopsy revealed a circumscribed detachment of the coronary arteries on the anterior side of the heart. The most unusual findings were lacerations of the vessel wall layers in these areas which could already be seen at the autopsy and were proven by histological examination.

Burn injuries caused by a hair-dryer — an unusual case of child abuse

About 1.4-26% burn injuries in children appear to be abusive in origin. A 2.5-year-old girl was referred to our institute because of suspected child abuse. Clinical examination and later interrogation of the mother revealed non-recent deep second degree burn injuries on both gluteal regions, caused by the partner of the mother by pressing a hand-held hair-dryer against the skin. The authors present the findings of this unusual method of child abuse.

Ungewöhnliche Manifestation einer traumatischen Aortenruptur

A 17-year-old man died as a rear seat passenger in a car involved in a head-on collision. The autopsy revealed a massive bilateral epipleural hematoma caused by a subtotal rupture of the thoracic aorta. The pleural dissection showed an unusually large distension on the left side and a remarkable resistence against mechanic pressure. The origin, progress and morphology are discussed in comparison with the literature. The article emphasizes the significance of this finding for clinical and forensic medicine.ZusammenfassungBei der Obduktion eines 17jährigen Mannes, der als Beifahrer im Fond eines Pkw nach einem Frontalaufprall noch an der Unfallstelle verstarb, konnte ein massives, beidseitiges epipleurales Hämatom festgestellt werden. Die Ursache für die Blutung war ein traumatischer, fast vollständiger Riß der thorakalen Aorta. Die Pleuradissektion zeigte neben der ungewöhnlich großen Ausdehnung auf der linke Seite auch eine bemerkenswerte Beständigkeit gegen mechanischen Druck. Es werden Entstehung, Ausbildung und Morphologie vergleichend mit der einschlägigen Literatur diskutiert und auf die Bedeutung dieser Erscheinung für die klinische und gerichtsmedizinische Praxis hingewiesen.

Impacts to the chest of PMHSs - Influence of impact location and load distribution on chest response

The chest response of the human body has been studied for several load conditions, but is not well known in the case of steering wheel rim-to-chest impact in heavy goods vehicle frontal collisions. The aim of this study was to determine the response of the human chest in a set of simulated steering wheel impacts. PMHS tests were carried out and analysed. The steering wheel load pattern was represented by a rigid pendulum with a straight bar-shaped front. A crash test dummy chest calibration pendulum was utilised for comparison. In this study, a set of rigid bar impacts were directed at various heights of the chest, spanning approximately 120mm around the fourth intercostal space. The impact energy was set below a level estimated to cause rib fracture. The analysed results consist of responses, evaluated with respect to differences in the impacting shape and impact heights on compression and viscous criteria chest injury responses. The results showed that the bar impacts consistently produced lesser scaled chest compressions than the hub; the Middle bar responses were around 90% of the hub responses. A superior bar impact provided lesser chest compression; the average response was 86% of the Middle bar response. For inferior bar impacts, the chest compression response was 116% of the chest compression in the middle. The damping properties of the chest caused the compression to decrease in the high speed bar impacts to 88% of that in low speed impacts. From the analysis it could be concluded that the bar impact shape provides lower chest criteria responses compared to the hub. Further, the bar responses are dependent on the impact location of the chest. Inertial and viscous effects of the upper body affect the responses. The results can be used to assess the responses of human substitutes such as anthropomorphic test devices and finite element human body models, which will benefit the development process of heavy goods vehicle safety systems.