Subdural haemorrhage sustained in a baby-rocker? A biomechanical approach to causation

An unconscious 8 weeks old infant was admitted to hospital and found to have bilateral, subdural and retinal haemorrhages. He died the following day. The explanation for the subdural haemorrhage put forward by his carers was that the infant had been in a baby-rocker and that the carers had seen the rocker being rocked vigorously by their 14 months old daughter on two separate occasions. This paper describes the biomechanics of an infant model in the particular baby-rocker used and determines the maximum forces generated, comparing them with the 'forces' thought to be compatible with the causation of subdural haemorrhage.

The potential and limitations of utilising head impact injury models to assess the likelihood of significant head injury in infants after a fall

The use of engineering principles in assessing head injury scenarios is of increasing significance in investigations into suspected child abuse. A fall scenario is often given as the history for a head injury to an infant. This paper addresses the basic engineering principles and factors to be considered when calculating the severity of a head impact after free-fall. The application of head injury models (HIMs) to ascertain the forces involved in childhood head injuries from impact is also discussed. Previous studies including Duhaime et al. [J. Neurosurg. 66 (1987) 409] and Nokes et al. [Forensic Sci. Int. 79 (1995) 85] have utilised HIMs for this purpose: this paper reviews those models most widely documented.The HIM currently considered the 'state-of-the-art' is the head injury criterion (HIC) and it is suggested that this model should be utilised for assessing head impact injury in child abuse cases where appropriate.

A novel approach to forensic investigation: three-dimensional kinematic and kinetic motion analysis

Following a domestic incident, a five-year-old child was pronounced dead on arrival at hospital. The subsequent post-mortem examination found that the cause of death was peritonitis as a result of a rupture of the duodenum. During the police interview, the main suspect alleged that the injury occurred whilst playing a game which involved standing on the child's abdomen and chest. A reconstruction of the game was performed using 3-dimensional kinematic and kinetic motion analysis to investigate the feasibility of the statement as described by the defendant. Presented is a summary of the investigation together with a description of kinematic and kinetic methods employed.

A biomechanical reconstruction of a wound caused by a glass shard--a case report

During the course of a criminal trial, an investigating pathologist is commonly asked how much force was required to produce an injury. This subjective opinion is based on the pathologist's previous experience of dealing with wounds inflicted with similar weapons. However, in the case of stab wounds inflicted by broken glass, it is unlikely that two glass fragments would be physically similar. In the case studied, two theories were examined: that a wound resulted from a thrown glass fragment or that it had been caused as a stab injury by the glass held in the bare hand. The investigation involved quantifying the energy required for human tissue penetration, comparison of sharpness, a biomechanical analysis of throwing actions and testing of the hypothesis that if the glass shard were used as a stabbing implement it would result in a cut to the hand.The investigation utilised a scientific methodology that reduced the need for speculative (though informed) opinion from the pathologist by producing quantitative results.

Dynamics of stab wounds: force required for penetration of various cadaveric human tissues

It is often said that once the skin has been penetrated no further force is required to produce penetration of underlying tissues. This experimental study has used technology which was not available to earlier investigators to examine this issue in detail. The results confirm the importance of skin penetration but indicate that the penetration of other tissues may also require significant force.

Clinical governance and the coroner

In the face of public expectation of uniformly high standards of medical practice and of open accountability, we suggest that the public interest would be served by a system of transparent, informed and independent scrutiny of those deaths that follow medical treatment, either in hospital or in the community. We do not believe that such a system operates at present in England and Wales or, indeed, that best practice may be achieved within current financial or legislative constraints. However, we suggest that the existing law allows greater involvement of the coroner in the investigation of deaths following medical treatment, should there be the professional desire for self-scrutiny and the political will to release resources to support that desire.

Detecting homicide in hospital

The Beverly Allitt case and the subsequent inquiry have focused attention on the detection of covert hospital homicide. Effective investigation can only take place if there is prompt recognition of circumstances that justify suspicion about a death and immediate action is taken to retrieve potentially vital evidence. The hospital itself must take responsibility for the detection of covert homicide. Confidence that such deaths will be uncovered by 'routine' investigation through the existing coroner system, including postmortem examination, is misplaced.

The use of personal health information in the coroner's inquiry

A pathologist appointed by the coroner may feel that his or her role is to review the medical notes, perform a post-mortem, examination and then interpret the findings in the light of clinical information and any other information received from the coroner, and include in the clinico-pathological summary a cause of death. We believe that such an approach is not in accordance with the legal position relating to coroners' inquests. The coroner has no automatic right to see the medical notes (and neither does the coroner's pathologist); where there is, or may be, dispute as to the circumstances leading to death, the proper way for information in the medical record to be presented at the coroner's inquest is for the maker of any note to give oral evidence. Where the cause of death requires interpretation of the clinical history or knowledge of any circumstantial evidence, a pathologist should refrain from giving a cause of death; such a task is for the court, having heard all the evidence-medical or not-relating to the death.

Impact characteristics of two types of police baton

A comparison study of the American style ASP extendible police baton with the conventional UK police wooden truncheon was performed. It was found that the ASP baton generated approximately twice the contact pressure than the conventional wooden truncheon. A discussion on the medical/legal aspects of the results are given.

The mechanics of stab wounding

The dynamics of stab wounds were investigated using a load cell connected to microcomputer-based measuring equipment. Two types of knife blade were attached to the load cell to assess the characteristics of stab wounds caused in pig tissue. The results show that as the blade progresses through the tissue it is resisted mostly by the skin, but a significant secondary resistance exists in the deeper muscle layers.

The immunocytochemical demonstration of a relative lack of nerve fibres in the atrioventricular node and bundle of His in the sudden infant death syndrome (SIDS)

Whilst examining the variation with age of the nerve fibre content of the cardiac conduction system (CCS), using an immunocytochemical approach, it became evident that in two sudden infant death syndrome (SIDS) cases there was a selective lack of S100 positive nerve fibres in the atrioventricular (AV) node and His bundle. In the present study therefore, the examination of CCS with S100 was extended to a further five SIDS cases and three cases of sudden explained death. Also, in addition to S100--which selectively marks Schwann cells associated with both myelinated and non-myelinated nerves--PGP 9.5 (protein gene product) was used to reveal the presence of nerve axonal elements associated with the CCS. The results showed a uniform presence of S100 and PGP 9.5 positive nerve fibres in the sinoatrial (SA) node, the AV node and His bundle tissue of all three control cases. In contrast, five out of seven SIDS cases showed a uniform lack of staining with these markers in the AV node and His bundle tissue, whilst in the two remaining cases it was present in greatly diminished amounts. Staining in the SA node, although present in all seven cases, was reduced when compared with the control cases. This is the first time the CCS of SIDS cases has been studied with immunocytochemical markers of nerve elements. The overall results taken in conjunction with the epidemiology of SIDS suggest that the lack of AV node and His bundle innervation most probably reflects a delay in the development or maturation of the nerve elements of the CCS, similar to that noted for other parts of the central and peripheral nervous systems in SIDS.

Deaths of British nationals abroad--a 10-year survey

Details are presented of all deaths of British Nationals abroad where a post mortem examination after repatriation was carried out in what is now the Wales Institute of Forensic Medicine. The problems posed by such deaths are discussed and the conclusion is drawn that without international uniformity in technique and documentation of medico-legal post mortem examinations, H.M. Coroner cannot be confident that all pathological evidence has been gathered from such an examination carried out in another country. A plea is made for international uniformity in the criteria for selection of deaths which require post mortem examination.

Further evaluation of immunocytochemical staining in the diagnosis of early myocardial ischaemic/hypoxic damage

The pattern of immunocytochemical staining with antibodies to caeruloplasmin, myosin, myoglobin and C-reactive protein seen in myocardium taken from deaths with macroscopic evidence of myocardial infarction and/or significant coronary artery atherosclerosis and from deaths with neither of these lesions has been correlated with H&E, PTAH and HBFP staining of myocardium and circumstances of each death indicative of antemortem hypoxia and/or ischaemia. Loss of staining with these antibodies correlated well with fuchsinorrhagia and both techniques are more sensitive than H&E and PTAH staining in the detection of early ischaemic/hypoxic damage to myocardium. However, their sensitivity is such that they appear to detect agonal changes and, therefore, cannot be used for specific diagnosis of early myocardial infarction.

Asphyxiation by glottic impaction of nasal secretions

An 84-year-old woman died suddenly 20 days after a head injury; a medical witness to the death described laboured breathing consistent with stridor. At postmortem examination, her larynx was found to be occluded by a firm mass of jelly-like material considered initially to be regurgitated food material. The microscopic features of this material were consistent with inspissated mucoid secretions from the nasopharynx. Relationship to cafe coronary and passage of a nasogastric tube are discussed.

Immunocytochemical diagnosis of early myocardial ischaemic/hypoxic damage

The sensitive and reliable dinitrophenyl (DNP) hapten sandwich staining (DHSS) procedure (B. Jasani et al., Virchows Arch (Pathol. Anat.), 406 (1985) 441-448) was used to study the distribution of immunoperoxidase staining seen with antibodies to seven protein markers in post-mortem heart tissue. This was obtained from 12 cases with macroscopic myocardial infarction and 17 cases without myocardial infarction (10 with and 7 without significant coronary artery atherosclerosis). The immunostaining patterns were compared with the appearances seen in adjacent sections stained by the routine haematoxylin and eosin (H & E) and phosphotungstic acid haematoxylin (PTAH) methods and a method previously recommended for the detection of early myocardial infarction, the haematoxylin basic fuchsin picric acid (HBFP) stain. Loss of immunostaining with an antibody to myoglobin was found to be a reliable and more objective marker of both early and established myocardial infarction compared with the histological stains. Antibodies to myosin, caeruloplasmin, C-reactive protein and pre-albumin gave similar but less reliable results, whilst those to complement factor C3b and alpha-1 anti-trypsin gave the least reliable results for early myocardial ischaemic/hypoxic damage. The immunocytochemical results are considered sufficiently encouraging to extend the work to a large number of sudden death cases in order to establish a new, more reliable approach to the detection of histologically latent ischaemic/hypoxic damage in the myocardium.

Dental anesthetic death. An unusual autoerotic episode

The details of an unusual autoerotic death are presented; the postulated method of induction of cerebral hypoxia was inhalation of nitrous oxide from a dental anesthetic machine; the theme of dental anesthesia, presumably an elaborate bondage fetish, recurred in documentary material found at the scene.

Incidence of familial hypercholesterolaemia in premature deaths due to coronary heart disease

Cholesterol estimations were performed on blood collected postmortem from a group of subjects coming to autopsy and showing that they had had a high risk for hypercholesterolaemia, and from an unselected group of subjects dying in hospital. Subjects from the first group had apparently been healthy, aged less than 45 years, had had no known risk factors for hyperlipidaemia, and showed extensive coronary artery atheroma (stenosis greater than 50% by diameter). Eleven cases from 485 consecutive autopsies fulfilled these criteria; three showed considerable hypercholesterolaemia (11.2, 11.8, and 21.6 mmol/L). Family studies confirmed the diagnosis of familial hypercholesterolaemia in one case; the other two remain unproven. Cholesterol measurement by cholesterol oxidase and quinoneimine dye production is subject to interference by haemolysis; provided that serum haemoglobin is less than 200 mg/dl, the cholesterol underestimate is less than 5%. The decline in serum cholesterol in the group of unselected subjects was 1.7 (0.3-4.9) mmol/L, 50.4 (28-84) h postmortem. Results are means and ranges for seven subjects. Measurement of cholesterol in serum obtained postmortem (provided that the sample is not grossly haemolysed) is a valid approximation of antemortem levels: this measurement should be made when autopsy reveals evidence of premature coronary heart disease. If hypercholesterolaemia is discovered, the diagnosis of familial hypercholesterolaemia, a common genetic disorder inherited in an autosomal dominant fashion, should be considered and appropriate family studies instituted.