Blunt carotid artery injuries challenge clinicians and biomechanical researchers. Investigations leading to the mechanism of injury are limited because of the occult nature of the injury and lack of detailed medical data in most common automotive-related databases. Detailed studies by Crash Injury Research Engineering Network Centers provide a unique dataset to fully evaluate injuries and injury mechanisms. The aim of this study is to obtain carotid artery injury data from CIREN and NASS databases and delineate the injury mechanics using biomechanical experiments. Four CIREN and nine NASS cases were identified. Biomechanical experiments demonstrated that the intima is the weakest layer of the artery that responds to stretch leading to tear in a traumatic situation, and the tear occurs secondary to local tensile loading of the vessel. Stress and strain corresponding to the intimal tear are 0.84 MPa and 32%. The artery has adequate reserve strength, i.e., residual deformation and load (32% and 46%), following the initiation of yielding of the intima. The quantification of the initial intimal disruption leading to subsequent neurological deficits offers a better understanding of the injury mechanics, hitherto not reported in literature. For the covering abstract see E135170.
Abstract