# A Review of Seatbelt Technologies and Their Role in Vehicle Safety
## 3 Results
### Other Passenger Categories Injuries  
Although seatbelt are effective in reducing injuries, certain categories of passengers may suffer specific injuries. The authors in [104] investigated in their study the differences in kinematics and injury risks between average female and male anthropometry in the case of whiplash-associated disorders in the rear. Using VIVA+ human body models, simulations were performed with detailed seat results showing equal injury risks in some scenarios, but the average female HBM had 1.5 times higher whiplash risk. Further on, ref. [105] examined sex-based differences in fatal crash fatalities, comparing newer model-year vehicles with advanced occupant protection systems to older models. Results show a significant reduction in female fatality risk relative to males in newer vehicles, with MY 2010-2020 showing a 6.3% difference. Vehicles with modern protection systems further lower female fatality risk, particularly for belted occupants. Older people, due to their fragility of bones, are more prone to fractures and other injuries, even in minor collisions. In [106], it is shown that in 2020, 17% of all crash fatalities were individuals aged 65 years or older. Crash data also revealed that for older occupants, thoracic-related injuries are among the leading causes of fatality. Elderly individuals are at increased risk of seatbelt-related thoracic fractures and injuries due to increased bone fragility, as stated in [98; 107; 108]. Older adults suffered thoracic injuries at a higher rate than older children--who suffered predominantly head injuries--and most vehicles did not have torso lateral airbags installed, which could have mitigated thoracic injuries. Side impacts in which younger occupants were killed were more severe than impacts that resulted in the death of an older occupant; however, vehicle damage and intrusion in many fatal impacts for both age cohorts appeared similar to that of consumer information testing. Large pickups and heavy vehicles were the striking vehicle in over half of all fatalities; vehicle designs and crash tests should continue to take this into consideration [109]. Using a matched cohort design and conditional Poisson regression, the authors in [33] estimated age-based relative risks of the outcomes associated with seatbelt use. The study results suggest that, while seatbelt are highly protective against fatal and severe injuries in multi-occupant crashes, older occupants do not receive the same seatbelt benefits as their younger counterparts for severe and torso injuries. Passengers not wearing seatbelt are at a significantly higher risk of serious injury and death. Injuries can range from those to the chest, back, and lower limbs to head, neck, and brain injuries. In [110], a study was conducted on 85 people involved in road accidents and states that while previous studies have highlighted the protective role of safety devices such as seatbelt's and airbags in mitigating injuries from vehicle collisions, they did not find significant associations between safety device utilization and the occurrence of facial fractures in vehicle collisions patients. The authors in [111] reaffirm the safety of the three-point seatbelt but draw attention to the fact that improper use of a seatbelt, including use of the two-point lap belt only, can lead to significant injury like shearing transection of the gastroduodenal junction. Three-point seatbelt harnesses are designed to secure over the sternum and hips, distributing deceleration forces in a way that decreases the risk of serious injury. Also, in [112], a chance fracture is mentioned, associated with other abdominal injuries in a study of a 21-year-old patient. Seatbelt marks are frequently seen on occupants after motor vehicle accidents. Over the years, the clinical significance of these marks has changed as restraint systems have evolved. With modern restraint systems, signs of a compromised occupant-restraint relationship are an important and easily identified bedside finding [93].