Gita Mall

Sex determination and estimation of stature from the long bones of the arm

The determination of sex and the estimation of stature from bones play an important role in identifying unknown bodies, parts of bodies or skeletal remains. In medico-legal practice statements on the probable sex of a decomposed body or part of a body are often expected even during autopsy. The present study was, therefore, restricted to few easily accessible dimensions from bones which were prepared only by mechanically removing soft tissues, tendons and ligaments. The specimens came from the Anatomical Institutes in Munich and Cologne from the years 1994-1998 including a total of 143 individuals (64 males and 79 females). The mean age was 79 years (46-108), the mean body height 161cm (134-189). The following measurements were taken: maximum humeral length (mean: 33.4cm in males; 30.7cm in females), vertical humeral head diameter (mean: 5.0cm in males, 4.4cm in females), humeral epicondylar width (mean: 6.6cm in males; 5.8cm in females), maximum ulnar length (mean: 26.5cm in males, 23.8cm in females), proximal ulnar width (mean: 3.4cm in males, 2.9cm in females), distal ulnar width (mean: 2.2cm in males; 1.8cm in females), maximum radial length (mean: 24.6cm in males; 22.0cm in females), radial head diameter (mean: 2.6cm in males, 2.2cm in females) and distal radial width (mean: 3.6cm in males; 3.2cm in females). The differences between the means in males and females were significant (P<0.0005). A discriminant analysis was carried out with good results. A percentage of 94.93% of cases were correctly classified when all measures of the radius were applied jointly, followed by humerus (93.15%) and ulna (90.58%). Applied singly, the humeral head diameter allowed the best distinction (90.41% correctly grouped cases), followed by the radial length (89.13%), the radial head diameter (88.57%) and the humeral epicondylar width (88.49%). The linear regression analysis for quantifying the correlation between the bone lengths and the stature led to unsatifactory results with large 95%-confidence intervals for the coefficients and high standard errors of estimate.

The neuropathology of heroin abuse

A broad spectrum of neuropathologic changes are encountered in the brains of heroin abusers. The main findings are due to infections, either due to bacterial spread from bacterial endocarditis, mycoses, or from HIV-1 infection. Other complications include hypoxic-ischemic changes with cerebral edema, ischemic neuronal damage and neuronal loss, which are assumed to occur under conditions of prolonged heroin-induced respiratory depression, stroke due to, for example, thromboembolism, vasculitis, septic emboli, hypotension, and positional vascular compression. Myelopathy is believed to be the result of an isolated vascular accident within the spinal cord due to an as yet unknown mechanism. A distinct entity, spongiform leukoencephalopathy, has been described mainly after inhalation of pre-heated heroin. A lipophilic toxin-induced process was considered to be due to contaminants and to be induced or enhanced by cerebral hypoxia, but a definite toxin could not be identified. At the cellular level, abnormalities in signal transduction systems and changes of various receptor densities have been reported. The exact etiology of the different neuropathological alterations associated with heroin abuse is still unclear, but may also be related to additional substances used as adulterants.

Determination of sex from femora

The determination of sex from bones or bone fragments considerably contributes to identifying unknown bodies or skeletal remains. Due to temporal change and regional differences anthropometric standards have to be constantly renewed. The present study provides measurements of femoral dimensions in a contemporary German population and analyses sexual dimorphism by discriminant analysis. Maximum length (male: 46.4+/-2.4 cm, female: 43.4+/-2.4 cm), maximum midshaft diameter (male: 3.1+/-0.2 cm, female: 2.8+/-0.2 cm), condylar width (male: 8.4+/-1.0 cm, female: 7.7+/-0.5 cm), vertical head diameter (male: 4.9+/-0.3 cm, female: 4.4+/-0.3 cm), head circumference (male: 15.7+/-0.8 cm, female: 13.8+/-1.0 cm) and transverse head diameter (male: 4.9+/-0.3 cm, female: 4.3+/-0.3 cm) were measured in 170 femora, 100 from male (age: 16-92 years, mean: 60.8 years; body height: 153-190 cm, mean: 171 cm) and 70 from female (age: 20-96 years, mean: 72 years; body height: 146-175 cm, mean: 161 cm) individuals. In the discriminant analysis (leave-one-out-method) 67.7% of cases could be grouped correctly with the maximum length alone, 72.4% with the maximum midshaft diameter, 81.4% with the condylar width, 86.8% with the vertical head diameter, 87.7% with the head circumference and 89.6% with the transverse head diameter. The stepwise procedure with all head measurements showed that the results for the transverse head diameter could not be improved. With all measurements subjected to stepwise procedure 91.7% of cases could be classified correctly combining midshaft diameter and head circumference (D=3.012xmidshaft diameter in cm+0.780xhead circumference in cm 20.569).

The neuropathology of cocaine abuse

Cocaine abuse represents a worldwide significant forensic issue as it is becoming widely recognized as one of the most dangerous illicit drugs in common use today. Besides cardiovascular complications, psychiatric and neurologic symptoms are the most common manifestations of cocaine toxicity. The latter include seizures, movement disorders and cerebrovascular complications. In chronic cocaine abusers morphological, physiological, and neurochemical abnormalities have been demonstrated by using neuroradiological techniques such as computed tomography, magnetic resonance imaging, positron emission tomography or single photon emission computed tomography. The spectrum of neuropathologic changes encountered in the brains of cocaine abusers is broad, but the major findings consist of ischemic and hemorrhagic stroke, subarachnoid and intracerebral hemorrhages and cerebral ischemia. Especially persons with underlying arteriovenous malformation or aneurysm are at risk for such events. Except for a few instances of vasculitis, the etiology of cocaine-related cerebrovascular accidents is still unclear. Besides pharmacologically-induced vasospasm, impaired hemostasis and platelet function and decreased cerebral blood flow have been proposed. At the cellular level, abnormalities in the expression of transcription factors and changes of brain neurotransmitter systems have been reported.

Unexpected death in persons with symptomatic epilepsy due to glial brain tumors: a report of two cases and review of the literature.

Two cases of unexpected death in persons with epileptic seizures due to a brain tumor are presented which encompassed an astrocytoma WHO grade II and an anaplastic astrocytoma WHO grade III. A 35-year-old man was found somnolent and disoriented at home. A computed tomography (CT) scan revealed a tumor of the right frontal lobe suggestive for an oligodendroglioma. During an angiographic examination the patient experienced an epileptic seizure. Some weeks later, the man was found dead in front of his house with a fresh bite mark of the tongue. Neuropathological examination revealed an astrocytoma WHO grade II of the right frontal lobe. A 47-year-old man plunged into a swimming-pool and was found submerged some minutes later. After resuscitation he survived comatose for 8 days but finally died due to severe hypoxic brain damage. He had been operated on a brain tumor of the temporal lobe 1 year before the accident. Neuropathological examination revealed residual tumor tissue at the operation site corresponding to an anaplastic astrocytoma WHO grade III. Although rare, death in persons with epileptic seizures due to brain tumors is an important mechanism of death encountered by the forensic pathologist.

Modelling postmortem surface cooling in continuously changing environmental temperature

Heat loss depends on the temperature gradient between body surface and environment. Skin cooling data in the forensic literature are scarce and models for skin cooling have not been developed. The dependence on the environmental temperature is a general problem in modelling postmortem cooling processes; most models of rectal cooling are therefore restricted to constant ambient temperatures. Since surface in contrast to core temperatures are highly sensitive to changes of ambient temperature, a model for skin cooling has to take into account such changes. The present study provides an estimator for the time-dependent function of the temperature decrease of the skin and presents a model of the cooling process. The formulae are developed on the basis of skin cooling data of the exposed skin of the forehead in a 40-year-old female (163 cm, 62.1 kg). The single exponential Newtonian model for the surface temperature T(S) valid for constant environmental temperature T(E):T(S)(t)=(T(S)(0)-T(E))e(-lambda(t))+T(E) is localized to small time intervals. By Taylor series expansions a differential equation directly providing an estimator for the temperature decrease rate lambda is derived. The solution of this differential equation represents the extended Newtonian model valid for non-constant environmental temperatures and non-constant temperature decrease rates. The extended model is tested successfully by reinserting the estimated values for the temperature decrease rate: the reconstructed and the measured skin temperature decrease curves completely overlap each other. The temperature decrease rate is a function of the difference between skin and environmental temperature and of the actual change of the skin temperature. A scatter plot of this function shows a structured cloud of points lying in one plane. The temperature decrease rate can thus be parametrized by a simple affine equation with three coefficients determined by linear regression. Inserting the affine equation in the extended Newtonian model leads to an inhomogeneous, non-linear differential equation which is solved by recursion. With knowledge of the initial temperature and the course of the environmental temperature the decrease of the skin temperature can be predicted with very good results. The model is validated with good results in 12 further experimental skin cooling curves of ten different individuals.

The diagnostic relevance of cerebral amyloid angiopathy in the setting of forensic pathology-a report of two cases and review of the literature

The neuropathological features seen in two cases with cerebral amyloid angiopathy (CAA) are presented. An 85-year-old woman was found comatose at home and died on the way to the hospital. The cause of death was an intracerebral hemorrhage (ICH) in the right parietal lobe. A 93-year-old woman with a history of traumatic subarachnoid hemorrhage was operated on for a chronic subdural hematoma. Intraoperatively, she developed severe ICH and died. The cause of death was an ICH in the parieto-occipital lobe. The morphology of the vessels was studied on differently stained sections and the neuropathological findings of the surrounding brain tissue were investigated. The affected vessels showed the characteristic alterations seen in CAA and included vascular amyloid deposition, fibrinoid necrosis, double-barrel lumen, splitting of the internal elastic lamina, defects of the vessel wall, and microaneurysms. Visualization of beta-amyloid protein was performed by histological and immunohistochemical methods. The immunohistochemistry for beta-amyloid was more sensitive and yielded better results compared with Congo red. In cases of ICH, CAA has to be considered in the differential diagnosis. Besides the use of Congo red stain, the application of beta-amyloid immunohistochemistry is requested to reliably make the diagnosis of CAA. Additional staining with a modified silver impregnation technique (AgNOR) is useful to detect associated neurodegenerative changes.

Supravital energy production in early post-mortem phase : Estimate based on heat loss due to radiation and natural convection

The temperature-based determination of the time since death in the early post-mortem (pm) period plays an important role in medico-legal practice. In contrast to the common opinion according to which convection and conduction are mainly responsible for post-mortem heat loss, a considerable part of energy is emitted by thermal radiation. The present paper concentrates on the heat loss due to radiation and natural convection. Since both heat transfer mechanisms depend on the temperature gradient between skin and environment, the skin temperature was measured in corpses of different constitution (lean, medium and obese) and its decrease fitted by a single-exponential model. Heat loss due to radiation was calculated according to the non-linearized form of the law of Stefan and Boltzmann, heat loss due to natural convection according to the semi-empirical thermodynamic laws; the shape of the body in supine position was approximated to a semi-cylinder of finite length. The power due to radiation ranged between 386kJ/h (lean) and 550kJ/h (obese), that due to natural convection between 307kJ/h (lean) and 429kJ/h (obese) initially. Cumulative energy loss amounted to 2167kJ (lean) and 4239kJ (obese) by radiation and 1485kJ (lean) and 2922kJ (obese) by natural convection up to 20h pm. The energy loss due to radiation plus natural convection initially exceeded the energy loss due the decrease of the energy content of the body (mass x heat capacity x temperature decrease). This surplus can be explained only by exothermal processes in the phase of intermediary life and directly provides lower bounds for supravital energy production. Cumulative supravital energy ranges between 1139kJ up to 5h pm in the lean and 2516kJ up to 10h pm in the obese corpses. The courses of supravital energies and powers are presented as functions of time. Under standard conditions like still air (no forced convection) and insulating ground (little conductive heat transfer), the lower bounds represent estimates for total supravital energy production.

Progressive idiopathic bilateral striato-pallido-dentate calcinosis (Fahr's disease) in a person with anabolic steroid abuse.

A 33-year-old male black student suddenly died during a basketball game. His previous medical history, including his neurological status, was unremarkable, but he was known to take anabolic steroids for several years. At autopsy, the cause of death was due to a fresh myocardial infarction. On neuropathological examination, there was extensive bilateral symmetrical calcification involving the basal ganglia as well as the dentate nuclei and the white matter of the cerebellum (Fahrs disease). A possible correlation between anabolic steroid-induced hypercalcemia and brain calcification is discussed.

Biomechanical analysis of stress distribution in the human temporomandibular-joint

The positions of the head of the mandible, of the articular disc and the outline of the temporal surface are digitized from sagittal MRI-scans of the temporomandibular joint of a 32-year-old subject in 5 different positions of occlusion. The stress distribution in the joint is calculated on the basis of these data. For each position of the condyle, the momentary center of rotation in the head of the mandible and the tangent attached to the temporal surface are determined. The line connecting these two points indicates the direction of the resulting compressive force. Furthermore, the extension of the area available to the force transmission is estimated. By means of these parameters the stress distribution is calculated independently from the position. The analyses show that the temporomandibular joint is slightly eccentrically loaded in all positions. The increase of the stresses is in all cases oriented caudo-ventrally. The results are verified in an anatomical specimen of the articular tuberculum. The trabecular structures as well as the subchondral bone-lamella of the articular tuberculum are functionally adapted to the analyzed stress situations.