Surface electromyography as a tool to study the head rest comfort in cars.

In this study, two methods were presented in order to evaluate objectively the comfort of head rests in cars using surface electromyography (SEMG). First, the Amplitude Probability Density Function (APDF) was computed. Extremely low level intensity activities were measured. No significant differences were observed on SEMG global activity between experiments with and without a head rest. Second, instead of computing one APDF, several APDF were calculated over time. Analyses focused on the rate of evolution of APDF parameters. This was a time varying APDF (TAPDF). This last method allowed a better diagnosis than the first one. For drivers, significant decreases in SEMG activity were observed when using a head rest. For passengers, a contradictory increase in SEMG activity was observed during experiments with a head rest. This observation was explained by the seat back angle chosen by passengers.

[The contribution of biomechanics to the safety of children inside motor vehicles]. / Les apports de la biomécanique a la sécurité des enfants a l'intérieur des voitures.

Because laws mandating use of seat belts by motor vehicle drivers and front seat passengers have been passed throughout the developed world, it is becoming increasingly common to see parents protected from injuries whereas their children are abandoned to the tragic effects of chance and biomechanics. In France, the situation is especially critical. The law passed in 1975 requiring that all children use the back seat has reduced the risk of death and severe injury but nevertheless affords inadequate protection: each year, among children aged 0 to 10 years, several hundred are killed and nearly 10,000 injured in car accidents. This situation can be decisively improved, as shown by the figures in the United States and most European countries where use of child restraint devices (CRD) is mandatory. CRDs are designed to protect the child in the event of an accident by reducing the risk of injury due to ejection or projection against the inside of the vehicle: they play the same role as the seat belt for adults. France is the European country with the lowest rate of use of CRDs and the highest rate of child deaths due to motor vehicle occupant injuries. To improve this situation, regulations are being developed by the French government; use of appropriate CRDs will be mandatory for all children aged 0 to 10 years starting on January 1 st, 1992.

Event-related potential assessment of attention and the orienting reaction in boxers before and after a fight.

Boxers' attention and orienting mechanisms were investigated using event-related brain potential recordings, before and after a fight. This study did not reveal any abnormalities of attention or detection processes. However, a slight deficit in the orienting reaction towards stimuli delivered in the right ear, related to a greater number of blows delivered on the left side of the head, was observed.

[Aortic ruptures in traffic accident traumatology]. / Les ruptures aortiques en traumatologie routière

8 cases of rupture of the aorta seen in a series of 62 autopsies were studied in the context of a multidisciplinary enquiry into road accidents. In the light of these cases, the literature and experimental findings, different mechanisms are described, an essential step in the prevention of this lesion which is the main cause of death in 15 p. cent of cases.

[Circular fractures of the skull base during traffic accidents]. / Les fractures circulaires de la base du crâne au cours des accidents de la route

With reference to 5 cases of circular fracture of the base of the skull occurring in relation to road accidents, the literature is reviewed. Two different types may be distinguished: --"compression" fractures, --"hyperextension' fractures, the latter being special on the basis of the site of the fracture line and the application of forces via the face or chin. Reconstruction of trajectories during accidents, on the basis of the anatomical lesions and the damage caused to vehicles, as well as the study of films made during the experimental reproduction of similar lesions, make it possible to explain the mode of production of these hyperextension fractures. Such understanding is essential to the study of safety precautions for vehicle occupants.