Use of a Porcine Cadaver Model as a Human Surrogate for Behind Armor Blunt Trauma

Abstract Current body armor design evaluation is based on legacy backface deformation criteria for protection despite limited medical basis. This uniform protection approach, which does not account for anatomical and physiological variability within the torso, may result in heavy armors that limit Warfighter mobility. To optimize armor design, anatomical and physiological regional injury tolerances must be assessed through live animal experimentation. Prior to this, the animal and human must first be compared to determine the animal model's viability as a surrogate for thoracoabdominal behind armor blunt trauma (BABT) response. Here, 74 BABT impacts were conducted using ten midsized male postmortem human subjects (PMHS) and ten 40-kg porcine cadavers in matched testing conditions over the lungs, liver, and sternum. Injury risk functions were generated from experimental data and compared across surrogates at each body region. The PMHS and 40-kg porcine cadaver correlated well for chest wall injuries in the lung region, and similarities were noted in high-severity impacts to the liver. Further, assessment of the backface intrusion injury risk function showed regional tolerance differences between anatomical regions, highlighting the need for separate region-specific design criteria. These results indicate that the 40-kg porcine cadaver was an appropriate torso surrogate for certain PMHS regions, such as the ribcage overlaying the lungs and the liver, in BABT conditions. As this study used cadaveric tissue, future studies should investigate the physiological components of BABT-induced injury in a live animal model, focusing on quantifying regional injury tolerances toward armor design optimization.