The assessment of airbag deployment and seatbelt use in preventing facial injuries.

Abstract

This study aimed to determine the effectiveness of airbags and seatbelts in the prevention of facial fractures and slight facial injuries in relation to the speed and kinetic energy experienced in frontal collisions. All cases of vehicle occupants who had been in frontal collisions and had subsequently been examined in the Institute for Emergency Medical Assistance and the Clinical Center of Montenegro in 2017 were analyzed. There were 29 cases of facial fractures (Group 1), 35 cases of slight facial injuries (including nondisplaced nasal fractures) (Group 2), and 26 cases of occupants who had suffered no facial injuries (control Group 3). In all assessed cases all of the subjects had been wearing a seatbelt and the airbag had deployed at the time of impact. A frontal collision is defined as a collision in which the principal force acts within a range of 90° from the longitudinal axis of the vehicle. Using the mass and the speed of the vehicles, the total kinetic energy (KE) of all frontal collisions being analyzed was calculated. The cut-off value of total KE in frontal collisions that were associated with either facial fractures or slight facial injury was estimated using a receiver operating characteristic (ROC) curve. The cut-off amounts of KE were then used to calculate the barrier equivalent velocity (BEV). The BEV for a vehicle of average mass was estimated to be 55.7km/h (34.6 mph) in Group 1, and 49.2km/h (30.6 mph) in Group 2. Airbags and seatbelts are effective in preventing facial injuries in vehicles of average mass that are traveling at speeds under 49.2km/h (30.6 mph) at the point of impact, but they do not protect from facial fractures when the vehicle speed exceeds 55.7km/h (34.6 mph).