Development of face surrogate for impact protection design for cyclist
Bicycle usage for exercise, recreation, and commuting to work in Australia shows that pedal cycling is the fourth most popular activity with 10.6% increase in participants between 2001 and 2007. As with other means of transport, accident and injury becomes common although mandatory bicycle helmet wearing has been introduced. The research aims to develop a face surrogate made of sandwich of rigid foam and rubber sheets to represent human facial bone under blunt impact. The facial surrogate will serve as an important test device for further development of facial-impact protection for cyclist. A test procedure was developed to simulate the energy of impact and record data to evaluate the effect of impact on facial bones. Drop tests were performed to establish a suitable combination of materials. It was found that the sandwich structure of rigid extruded-polystyrene foam (density of 40 kg/m with a pattern of 6-mm-holes), Neoprene rubber sponge, and Abrasaflex rubber backing, had impact characteristics comparable to that of human facial bone. In particular, the foam thickness of 30 mm and 25 mm was found suitable to represent human zygoma (cheekbone) and maxilla (upper-jaw bone), respectively. Keywords—Facial impact protection, face surrogate, cyclist, accident prevention
The circumstances and scope for prevention of maxillofacial injuries in cyclists.
A prospective study of cyclists with maxillofacial injuries attending Accident and Emergency departments in South Wales was carried out over a 12 month period. 65% of the 104 accident victims were aged under 14 years, and 81% were male. Only 14% were wearing helmets. Injuries were mapped to 9 facial zones. Nearly half the victims sustained injury to the central facial zone. There was an association between head injury (HI) and the location of impact on the face (p < 0.0001 Chi-square = 41 df = 8), the nature of the accident (p < 0.012 Chi-square = 10.9 df = 3), and type of injury in the impact zone (p < 0.007 Chi-square = 13.4 df = 4). More patients with facial injuries but without facial bone fractures sustained HIs than those with fractures. The facial skeleton may protect the brain by absorbing impact. The high incidence of midface injuries could be reduced by incorporating a facebar in helmet design.
Head injuries in helmeted child bicyclists.
OBJECTIVE: To determine the characteristics and the severity of head and facial injuries to helmeted child bicyclists, and whether the helmet contributed to the injury, and to study factors related to bicycle accidents. DESIGN: Retrospective review of two case series. Children sustaining head injury while not wearing helmets were studied as a form of reference group. SETTING: Large paediatric teaching hospital. SUBJECTS: 34 helmeted child bicyclists and 155 non-helmeted bicyclists, aged 5-14 years. MAIN OUTCOME MEASURES: Number of injuries, type of injuries, injury severity score, deaths, and accident circumstances. RESULTS: 79% of the head injuries of the helmeted child group were mild and two thirds of these had facial injuries. Children in the helmet group were in a greater proportion of bike-car collisions than the no helmet group and at least 15% of the helmets were lost on impact. There were no injuries secondary to the helmet. CONCLUSIONS: Most of the head injuries sustained by the helmeted children were of mild severity and there was no evidence to suggest that the helmet contributed to injury. Nevertheless, consideration should be given to designing a facial protector for the bicycle helmet and to improvement of the fastening device.