MATERIAL STRENGTH AND MECHANICAL FAILURE MODE OF PORCINE SPINAL DURA MATER UNDER A PRESSURIZED LOADING CONDITION

Mechanical damage to the meninges, which protect the spinal cord from blunt external forces, can cause idiopathic cerebrospinal fluid (CSF) leakage. This is probably because even a small meningeal failure leads to the leakage of CSF out of the subarachnoid space. However, the dura mater, the outermost layer of the meninges, is especially resilient and structurally tough. Moreover, CSF leakage can be caused by daily activities, including coughing, sneezing, and falling. Because of these contradicting facts, the essential mechanism of CSF leakage is difficult to understand. Recently, extensive efforts have been made to elucidate the mechanism of traumatic and impact-related injuries through computational simulations. It is crucial to comprehend the actual failure mode of biological materials under in vivo-like injurious loading conditions to enhance the accuracy of injury prediction. Therefore, in this study, we focused on the relationship between the intrinsic shape of wrinkles formed on the dural surface and the mechanical failure mode of the spinal dura mater. We found that a generated crack runs along the microscopic wrinkles in the longitudinal direction even when the spinal dura mater is statically pressurized.