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The frequency of pelvic fractures is 10%-14% in side impact crashes. In this study, seventeen side impact sled tests were performed using a Heidelberg-type seat fixture. The pelvis along with the rest of the torso impacted a sidewall in these tests. This series of runs provided a good test of injury criteria performance for a variety of impact surfaces. Pelvic injury criteria based on force, acceleration, compression, and the viscous criterion were evaluated. Force was found to be a good criterion according to both the Weibull and Logist analysis. A promising new injury criterion tested was “Average Force” (Favg). It reflects the rate of momentum transfer to the pelvis during a side impact. The slope of the pelvic momentum trace, from 10 to 90% of its peak, is the time rate of change of momentum, and has the dimension of force. In a 32 km/h (20 mph) impact, Favg is 5 kN for a 25% probability of an AIS 2 pelvic injury (maximum likelihood 0.0135).

Seventeen side impact sled tests were performed using a horizontally accelerated sled and a Heidelberg-type seat fixture. In these tests the subject's whole body impacted a sidewall with one of three surface conditions: 1) a flat, rigid side wall, 2) an unpadded side wall with a 6″ pelvic offset, or 3) a flat, padded side wall. Forces, deformations and accelerations of the thorax were measured. VCmax emerged as a good injury criterion in this test series. In the WSU-CDC tests VCmax was 0.86 m/s for the half-chest at 25% probability of AIS 4. In addition, a new criterion we have termed “Average Spine Acceleration” (ASA) performed well. ASA is obtained by integrating the T12-y spinal acceleration to obtain spine velocity. The slope of the spine velocity trace is the Average Spine Acceleration, and reflects the rate of momentum transfer to the body during an impact.