The effect of seatbelt pre-tensioners and load limiters in the occurrence of MAIS 2%2B and MAIS 3%2B abdominal injuries in real-world frontal crashes

Abstract

Abdominal injuries are still frequent in motor vehicle crashes despite advancements in automotive safety and improvements to restraint systems. Pre-tensioners and load limiters have been incorporated into newer vehicles to improve seatbelt effectiveness. The objective of this study was to assess the effect of seatbelt pre-tensioners and load limiters in the occurrence of AIS 2%2B and AIS 3%2B injuries to the abdominal region in real-world frontal crashes. Seatbelt characteristics from NHTSA’S NCAP crash tests were incorporated to data from NASS CDS (crash years 2000-2015) and CISS (crash years 2017-2021) and used in multivariate logistic regressions. Only belted front row occupants older than 15 years old involved in frontal crashes with no rollovers were included in the analysis. Overall, the spleen and liver were the most frequently injured abdominal organs, but injuries to the lower abdominal organs gained importance at AIS 3%2B severity level. At AIS 2%2B level, the presence of a shoulder belt pre-tensioner increased the probability of abdominal injury (OR = 1.36); at AIS 3%2B level, the higher the force of the lap belt pre-tensioner, the greater the risk of abdominal injury (OR = 1.30). Load limiters presented an interaction with delta-v at AIS 2%2B level, and high force load limiters increased the likelihood of AIS 3%2B abdominal injury (OR = 1.50). Occupant and vehicle age, being a driver, delta-v, and oblique collision components increased the risk of AIS 2%2B and AIS 3%2B abdominal injuries. Occupants that were female, taller, and presented greater BMI were also at higher risk of AIS 2%2B abdominal injury.