This paper evaluates a recently published comprehensive knee-thigh-hip (KTH) injury criterion through its application to the Hybrid III 50th percentile male (HIII-50M) and 5th percentile female (HIII-5F) dummies in frontal crash tests along with a comparison with real world KTH injury risk in frontal crashes. This criterion, developed by Rupp et al. (2009) (Rupp-KTH criterion), determines risk of injury to the hip, femur, and knee using the peak compressive femur force and impulse.
Femur load cell data from various frontal crash tests were analyzed using the Rupp-KTH criterion. The risk of KTH injuries as calculated with this criterion in the various crash conditions was compared to that observed in real world frontal crashes using the National Automotive Sampling System-Crashworthiness Data Systems (NASS-CDS) data files. The relative proportion of knee, thigh, and hip injuries predicted by the Rupp-KTH criterion was also compared to that observed in real world crashes.
The Rupp-KTH criterion predicts an overall KTH injury risk reflective of real world risk with unbelted Hybrid III dummies, but under-predicts real world injury risk for belted dummies. The proportion of hip injuries among all KTH injuries is predicted reasonably well for unbelted occupants and underpredicted for belted occupants. Dummy interaction with the knee bolster in different restraint conditions likely affects the level of agreement between predicted and observed injury risk.
This study applied injury criteria to Hybrid III dummy responses in specific crash conditions and seating configurations. Injury risk prediction may be improved with other dummy designs or crash environments.