Effect of age on injury outcome in passenger car frontal crashes

The senior population is growing rapidly across most motorised countries resulting in an increasing number of elderly motor vehicle users. Accident data from the UK Cooperative Crash Injury Study (CCIS) were analysed to examine the relationship between age and injury outcome for belted front seat occupants in passenger car frontal crashes. Results showed that, for similar frontal crash characteristics, the MAIS outcome was more severe for older front seat occupants (65+) and they were more likely to be fatally injured compared to middle-aged and younger occupants. The chest was the most frequently injured body region. The older occupants sustained more injuries to the chest region compared to their younger counterparts and these injuries were predominately skeletal injury induced by seat belt forces. Older occupants had a higher rate of multiple rib fractures compared to younger and middle aged occupants. The increase in the number of rib fractures showed a strong association with increase in intrathoracic organ injury. These results suggest that older occupants are more vulnerable to serious injury to the chest region in frontal impacts. Vehicle crashworthiness systems that account for differences in age related injury tolerance could have a positive effect on injury outcome in frontal car crashes

Injury patterns in side collisions - a new look with reference to current test methods and injury criteria

The UK in-depth data, describing the causation of injuries to casualties in side impacts, was examined for crashes occurring between 1992 and 1998. Slightly more casualties died in side impacts than in frontal crashes, and one third were seated on the side away from the collision. The collision severity was compared with the European and US legal test procedures and most MAIS 3+ survivors were observed to be in crashes above the severity of the test. The mean delta-V for the fatal group was 48 km/h compared with typically 25 km/h in the test. The most commonly injured body regions of both survivors and fatalities were the head, thorax and lower extremity. The lower extremity was the most frequent site of AIS 2+ injuries of survivors and fractures to the femur and tibia were highlighted, these injuries are not assessed by existing dummies

An in-depth study of abdominal injuries sustained by car occupants in frontal crashes

Currently, neither abdominal injury risk nor rear seat passenger safety is assessed in European frontal crash testing. The objective of this study was to provide real world in-depth analysis of the factors related to abdominal injury for belted front and rear seat occupants in frontal crashes. Rear occupants were significantly more at risk of AIS 2+ and 3+ abdominal injury, followed by front seat passengers and then drivers. This was still the case even after controlling for occupant age. Increasing age was separately identified as a factor related to increased abdominal injury risk in all seating positions.One exception to this trend concerned rear seated 15 to 19 year olds who sustained moderate to serious abdominal injury at almost the same rate as rear occupants aged 65+.No strong associationwas seenbetween AIS 2+ abdominal injury rates andgender. The majority of occupant body mass indices ranged from underweight to obese. Across that range, the AIS 2+ abdominal injury rates were very similar but a small number of very obese and extremely obese occupants outside of the range did exhibit noticeably higher rates.An analysis of variance in the rate of AIS 2+ abdominal injury with different restraint systems showed that simple belt systems,as used by most rear seat passengers, were the least protective. Increasing sophistication of the restraint system was related to lower rates of injury. The ANOVA also confirmed occupant age and crashseverity as highly associated with abdominal injury risk. The most frequently injured abdominal organs for front seat occupants were the liver and spleen. Abdominal injury patterns for rear seat passengers were very different. While they also sustained significant injuries to solid organs, their rates of injury to the hollow organs (jejunum-ileum, mesentary, colon) were far higher even though the rate of fracture of two or more ribs did not differ significantly between seat positions. These results have implications for the design of restraint systems, particularly in relation to the occurrence of abdominal injury. They also raise issues of crash protection for older occupants as well as the protection afforded in different seating positions. ©Annals of Advances in Automotive Medicine

Multiple impact crashes - consequences for occupant protection measures

Much analysis of accident data and most crash tests focus on single impacts. However, in reality, multiple impacts account for a large proportion of serious injury accidents and are expected to become a larger proportion as countermeasures, developed primarily for single mode impacts, take effect. It is proposed that multiple impacts should be considered separately since consideration of their characteristics may have implications for occupant protection. This study investigates multiple impacts in more detail and, in particular, explores their relative importance in the accident population, analyses their characteristics and discusses some possible consequences for occupant protection measures

Improving the chest protection of elderly occupants in frontal crashes using SMART load limiters

Objective: To determine whether varying the seat belt load limiter (SBL) according to crash and occupant characteristics could have real-world injury reduction benefits in frontal impacts and, if so, to quantify those benefits. Methods: Real-world UK accident data were used to identify the target population of vehicle occupants and frontal crash scenarios where improved chest protection could be most beneficial. Generic baseline driver and front passenger numerical models using a 50th percentile dummy were developed with MADYMO software. Simulations were performed where the load limiter threshold was varied in selected frontal impact scenarios. For each SBL setting, restraint performance, dummy kinematics, and injury outcome were studied in 5 different frontal impact types. Thoracic injury predictions were converted into injury probability values using Abbreviated Injury Scale (AIS) 2+ age-dependent thoracic risk curves developed and validated based on a methodology proposed by Laituri et al. (2005). Real-world benefit was quantified using the predicted AIS 2+ risk and assuming that an appropriate adaptive system was fitted to all the cars in a real-world sample of recent frontal crashes involving European passenger cars. Results: From the accident data sample the chest was the most frequently injured body region at an AIS 2+ level in frontal impacts (7% of front seat occupants). The proportion of older vehicle front seat occupants (>64 years) with AIS 2+ injury was also greater than the proportion of younger occupants. Additionally, older occupants were more likely to sustain seat belt–induced serious chest injury in low- and moderate-speed frontal crashes. In both front seating positions, the low SBL provided the best chest injury protection, without increasing the risk to other body regions. In severe impacts, the low SBL allowed the driver to move dangerously close to the steering wheel. Compared to the driver side, greater ride-down space on the passenger side gave a higher potential for using the low SBLs. When applying the AIS 2+ risk reduction findings to the weighted accident data sample, the risk of sustaining an AIS 2+ seat belt injury changed to 0.9, 4.9, and 8.1% for young, mid, and older occupants, respectively, from their actual injury risk of 1.3, 7.6, and 13.1%. Conclusions: These results suggest the potential for improving the safety of older occupants with the development of smarter restraint systems. This is an important finding because the number of older users is expected to increase rapidly over the next 20 years. The greatest benefits were seen at lower crash severities. This is also important because most real-world crashes occur at lower speeds

The influence of European air bags on crash injury outcomes

The UK Co-operative Crash Injury Study currently includes data on 205 seat belted drivers from frontal impacts in which an air bag deployed; of these, 142 suffered some degree of injury. To detect the influence of frontal air bags, the distribution of injury over the body regions of these drivers was compared to that of a much larger group from vehicles without air bags. The injured drivers from air bag vehicles showed relatively fewer head injuries, especially fractures, and relatively more arm injuries. No abnormal types of injury or circumstances of injury were identified for the air bag group. Air bags generally appear to deploy at vehicle impact severities that pose a statistical risk of significant head injury, and also in a proportion of lower severity impacts. As a group, the air bag equipped vehicles were larger, more modern, and more often fitted with seat belt pretensioners than the non air bag vehicles, with an older and more male driving population

An Evaluation of airbag benefits/disbenefits in European vehicles - a combined statistical and case study

Any restraint system carries a certain risk of injury from the system itself. It is therefore vital to know the balance of that risk compared to the overall benefits of the system. The objectives of this study were to address those questions by a thorough case review of in-depth real world cases to find problems associated with airbag deployment followed by examining the nature, frequency and mechanisms of AIS ≥ 2 head/face and chest injuries in European vehicles, with and without airbags. Belted and unbelted drivers were examined separately. The analysis considered only frontal impacts.Any restraint system carries a certain risk of injury from the system itself. It is therefore vital to know the balance of that risk compared to the overall benefits of the system. The objectives of this study were to address those questions by a thorough case review of in-depth real world cases to find problems associated with airbag deployment followed by examining the nature, frequency and mechanisms of AIS ≥ 2 head/face and chest injuries in European vehicles, with and without airbags. Belted and unbelted drivers were examined separately. The analysis considered only frontal impacts

Belted driver protection in frontal impact - what has been achieved and where do future priorities lie?

Examining Injuries to real people in real crashes is the ultimate way to validate improvements in crashworthiness as well as to determine where future priorities lie. Examination of U.K national statistics showed that, coincident with the introduction of airbags and better restraints there was a significant fall in the rates of killed/seriously injured car occupants as well as a significant fall in the number of car occupant fatalities. Interrogation of the UK in-depth crash injury data for belted driver injury risk in frontal crashes showed substantial reductions in injury risk for the head in newer cars. Risk of serious injury to the chest, thigh and leg showed little change between older and newer vehicles despite controlling for occupant parameters

Air temperature and inflammatory and coagulation responses in men with coronary or pulmonary disease during the winter season

Background and Objective Air temperature changes are associated with increased cardiovascular and respiratory risk, but the roles of inflammatory and coagulation markers are not well understood. We investigated the associations between temperature and several blood markers in patients with coronary heart disease (CHD) and pulmonary disease (PD). Methods Two studies were conducted in Erfurt, Germany, over two successive winters. 578 and 381 repeated blood measurements were collected from 57 CHD and 38 PD patients, respectively. Data on patient characteristics and disease history were gathered at baseline. Meteorological data were collected from existing networks. Associations were analysed using additive mixed models with random patient effects. Effect modification by diabetes status was investigated only in CHD patients, as only two PD patients had diabetes. Results Mean daily air temperature varied between -13 degrees C and 16 degrees C in both study periods. A 10 degrees C decrease in the 5-day temperature average before blood withdrawal led to an increase in platelet counts (% change from the mean: 3.0%, 95% CI 0.6% to 5.5%) and fibrinogen (5.5%, 1.3% to 9.7%), no change in C-reactive protein in PD patients, and a decrease in C-reactive protein in CHD patients. A 2-day delayed increase in factor VII associated with temperature decrease was seen in CHD patients (4.9%; 0.7% to 9.2%), while PD patients showed no effect. `Effects in CHD patients without diabetes' into `Effects on factor VII in CHD patients without diabetes'. Conclusions This study suggests that temperature decrease is associated with change in several blood parameters. The complex interplay of blood markers at low temperature may contribute to the observed association between cold and cardiovascular mortality and morbidity

An opinion survey on road side speed control devices

Vehicle speeds have been identified as a contributory factor to the severity of road traffic crashes (Perez et al., 2007; World Health Organisation [WHO], 2013). Considering that car manufacturers are consistently portraying speed as a key performance feature or a higher standard of sporting performance, it is important to establish the true worth of speed to drivers and how vehicle speeds can be managed effectively if road crash deaths are to be reduced. This paper presents the findings of an online questionnaire conducted in the United Kingdom (UK) to ascertain the opinion about six selected roadside speed control devices. These speed control devices comprised two main categories; punitive (example; speed camera) and non-punitive (example; ‘Bend Ahead’ flashing sign) devices. In total 502 respondents were obtained from drivers and/or motorcyclists, 52% of whom were male. There were 76.1% of drivers who had more than ten years of driving experience and 32.9% who had never had a crash as a driver. The results indicate that drivers are knowledgeable about the purpose of the speed control devices. More people indicated that speed cameras had an influence on their driving speed than the vehicle activated signs which is understandable considering that speed cameras have punitive consequences. In general, respondents expressed positive views about the speed control devices. Other findings about the speed control devices are presented in this paper