Comparison of the biomechanical behavior of the liver during frontal and lateral deceleration.

ABSTRACT

BACKGROUND: The trunk of a car occupant can be injured by a frontal or lateral impact. Lesions can be either intrusion injuries or due to the effects of deceleration alone. The aim of this study conducted with human cadavers was to explore the effects of deceleration on the liver during frontal or lateral deceleration. METHODS: Trunks previously instrumented with accelerometers in three sites, the left and right lobes of the liver and the retrohepatic inferior vena cava, were subjected to substantial deceleration in three orientations frontal, left, and right lateral. The anatomic consequences and deceleration data were measured. A deceleration ratio was defined as a peak deceleration measured in the liver divided by peak deceleration imposed on the trunk. RESULTS: Peak deceleration imposed on the trunks was up to 60 g, which caused peak deceleration up to 26 g in the liver. No anatomic injury was observed. For each orientation, deceleration ratios were not significantly different among the three sites (p = 0.64) or between left and right lateral decelerations (p = 0.12). Deceleration ratios were significantly different (p = 0.001) between frontal (3 sites combined) and lateral (3 sites of left and right lateral orientations combined) decelerations 39.4% (+/-6) versus 48.4% (+/-11). CONCLUSIONS: In conclusion, at tested decelerations, under the hepatic injury threshold, cadaveric liver seemed to be subjected to higher deceleration when the trunk was decelerated in lateral than in frontal direction, without terminal impact.