Human spine behaviour under thoracic and pelvic lateral impacts – comparison with WorldSID dummy behaviour

Human spine behaviour under lateral impacts was studied through Post Mortem Human Subject (PMHS) experiments carried out within the European project SIBER (SIB, 2000) and previous tests conducted in a French PREDIT Program (BOUQUET, 1994). The aim of these experiments is to characterise the coupling between the upper and lower torso created by the lumbar spine. For this purpose, PMHSs were struck to the thorax and then to the pelvis at different velocities: 5 thoracic impacts were conducted at 4 m/s, 5 pelvic tests at 6.6 m/s. In addition, previous tests carried out in similar conditions were re-analysed (5 thoracic impacts at 3.3 m/s, 5 others at 5.5 m/s and 10 pelvic impacts at 6.6 m/s). Impactor force, subject accelerations at Tl, T4, T8, T12 and sacrum were recorded, while 2D motion of the subject's spine was filmed. Two WorldSID dummies (prototype and pre-production version) were submitted to the same type of impacts to assess their lumbar spine behaviour.The dummy responses were evaluated against corridors defmed from PMHS responses. The WorldSID dummy showed an improvement with respect to the current European regulatory dummy. Its lumbar spine allowed a more biofidelic coupling between its upper and lower torso which created a more human-like kinematics.