Session IV - Geriatrics
The Actual Injury Situation of the Geriatric Road Users: A Medical and Technical Accident Analysis
Martinus Richter, MD1; Hans-Christoph Pape, MD1; Dietmar Otte, MD2; Thomas Gosling, MD1; Christian Krettek, MD, FRACS1;
Purpose: For the orthopedic surgeon, the importance of injuries in geriatric road users is greater than ever because of the increase in the proportion of senior citizens in our society. A medical and technical analysis of the actual injury situation of geriatric road users was performed to determine the difference between younger road users and to create a basis for effective prophylaxis.
Methods: Traffic accident reports from a technical and medical investigation at the accident scene and the first medical institution providing care were analyzed for the involvement of road users more than 65 years of age and for the following parameters: demographic data, Abbreviated Injury Scale (AIS) score, Maximum AIS (MAIS), Injury Severity Score (ISS), Delta-v, and collision speed.
Results: From 1985 to 1998, 16,453 (53.3%) of the 30,575 involved road users were injured in 12,309 traffic accidents; 6.0% (N = 1,843) of the involved road users and 7.7% (N = 1,260) of the injured were more than 65 years of age. The mean age of the injured geriatric road users (N = 1,260, 68.4%) was 74.4 years (range, 66 to 98), and 44% were male. Of the injured geriatric road users, 48.2% sustained only minor injuries (MAIS 1), 46.6% had severe injuries (MAIS 2 to 4), and 5.1% had the severest injuries (MAIS 5 to 6). Multiple injuries were registered in 45%. Head injuries occurred in 29% of the injured geriatric road users and lower extremity injuries in 57%. The mean ISS among the injured was 7.3 (range, 1 to 75). Of the injured geriatric road users, 59.8%were treated as outpatients, 21.4% stayed in the hospital for more than 1 week, and 9.7% died. Injured geriatric road users were car occupants in 39.5%, bicyclists in 27.4%, pedestrians in 29.6%, truck occupants in 1.8%, and motorcyclists in 1.7% of the traffic accidents. Cars were collision opponents in 79% of pedestrian and 71% of bicycle accidents. Among all involved geriatric road users (N =1,843), 92% of the 1,059 car occupants were restrained and 5% were protected with an airbag. The injuries of the car occupants were caused in 80% by impact with the inner vehicle surface and in 20 % by a squeezing mechanism. Geriatric road users wore a helmet as a bicyclist in 0.3% of cases. Sixty percent of the geriatric road users in cars (N = 575) remained uninjured, in contrast to 1.1% of the bicyclists and 0.8% of the pedestrians. Severe injuries (MAIS 2) occurred in 36.5% of the injured geriatric road users as car occupants (unrestrained: 58%, restrained: 34%), 57.4% of the bicyclists, and 65.4% of the pedestrians. Ninety-one percent of the bicyclists or pedestrians were involved in accidents in urban areas. Severe injuries (MAIS 2) occurred in 24% of the bicyclists and pedestrians in crashes with a collision speed of less than 30 km/h (18.6 mph) and in 78% in crashes with a collision speed of more than 50 km/h (31 mph). Half of the crashes involving bicyclists or pedestrians could have been avoided if the colliding motor vehicle would have been driven 15 km/h (9.3 mph) slower. Of younger road users (15 to 65 years of age, N = 26,416), 53% were injured overall (mean ISS, 5.18). Among those injured, 60.3% were car occupants, 16.4% were pedestrians, and 7.5% were bicyclists (MAIS 2 [among the injured]; car occupant, 30.2%; bicyclist, 34.0%; pedestrian, 54.1%). Of the injured, 75.7% were treated as outpatients, 9.4% stayed more than 1 week in the hospital, and 4.1% died. Ninety percent of the car occupants (73% of the involved road users) were restrained.
Conclusion/Significance. Elderly road users have a higher injury incidence and severity than those who are younger, especially as pedestrians and bicyclists. Improvement of the outer design of cars and the use of bicycle helmets would be helpful for those injured. Speed is a considerable factor, because the injury severity for bicyclists and pedestrians increases progressively above a collision speed of 50 km/h (31 mph). In cars, elderly passengers are more severely injured, even when they are belt-protected. An optimized inner car design concerning energy absorption may have a preventive effect because the majority of injuries are caused by direct impact. Legislation regarding the use of bicycle helmets would also be promising.