Obese Occupant Response in Reclined and Upright Seated Postures in Frontal Impacts. Stapp Car Crash J 2022 Nov;66:31-68
Date
09/21/2023Pubmed ID
37733821DOI
10.4271/2022-22-0002Scopus ID
2-s2.0-85150993131 (requires institutional sign-in at Scopus site) 6 CitationsAbstract
The American population is getting heavier and automated vehicles will accommodate unconventional postures. While studies replicating mid-size and upright fore-aft seated occupants are numerous, experiments with post-mortem human subjects (PMHS) with obese and reclined occupants are sparse. The objective of this study was to compare the kinematics of the head-neck, torso and pelvis, and document injuries and injury patterns in frontal impacts. Six PMHS with a mean body mass index of 38.2 ± 5.3 kg/m2 were equally divided between upright and reclined groups (seatback: 23°, 45°), restrained by a three-point integrated belt, positioned on a semi-rigid seat, and exposed to low and moderate velocities (15, 32 km/h). Data included belt loads, spinal accelerations, kinematics, and injuries from x-rays, computed tomography, and necropsy. At 15 km/h speed, no significant difference in the occupant kinematics and evidence of orthopedic failure was observed. At 32 km/h speed, the primary difference between the cohorts was significantly larger Z displacements in the reclined occupant at the head (190 ± 32 mm, vs. 105 ± 33 mm p < 0.05) and femur (52 ± 18 mm vs. 30 ± 10 mm, p < 0.05). All the moderate-speed tests produced at least one thorax injury. Rib fractures were scattered around the circumference of the rib-cage in the upright, while they were primarily concentrated on the anterior aspect of the rib-cage in two reclined specimens. Although MAIS was the same in both groups, the reclined specimens had more bi-cortical rib fractures, suggesting the potential for pneumothorax. While not statistical, these results suggest enhanced injuries with reclined obese occupants. These results could serve as a data set for validating the response of restrained obese anthropometric test device (ATDs) and computational human body models.
Author List
Somasundaram K, Humm JR, Yoganandan N, Hauschild H, Driesslein K, Pintar FAAuthors
Frank A. Pintar PhD Chair, Professor in the Biomedical Engineering department at Medical College of WisconsinKarthik Somasundaram PhD Assistant Professor in the Biomedical Engineering department at Medical College of Wisconsin
MESH terms used to index this publication - Major topics in bold
CadaverHumans
Obesity
Posture
Rib Fractures
