Case report of sudden death after a gunshot wound to the C2 vertebral bone without direct spinal cord injury: Histopathological analysis of spinal-medullary junction

Gunshot wounds (GSW) are one of the most common causes of penetrating spinal injury, however few data are available regarding GSW causing an indirect fatal nervous tissue injury, such as that induced by the concussive force secondary to the bullet penetration. This report describes a rare case of a death following a GSW spine injury at the level of C2 vertebral body, without direct contact with the spinal cord, as seen with computed tomography scan performed soon after the death. At autopsy, vertebral canal and dura mater, as well as spinal cord and medulla oblongata, appeared devoid of pathologies and/or lesions, major viscera were unaltered. The cause of death was attributed to a cardiorespiratory arrest subsequent to the GSW injury of the C2 vertebral bone. Histopathological analysis of spinal cord and medulla oblongata was performed by means of conventional stainings, and glial fibrillary acidic protein (GFAP) and Neurofilaments 200 kD (NF) immunohistochemistry. Histological alterations stood out against a tissue with no other evident sign of neuropathology, and could be observed from the caudalmost part of the medulla oblongata to the level of the inferior olivary nucleus. Main structural changes were found in the white matter, involving often the adjacent gray matter, where they appeared as multiple scattered areas of degeneration, lacking the usual staining affinity, and showing a disrupted fibrillary pattern as evidenced by myelin staining, and GFAP- and NF-immunolabelling. The shock wave secondary to the impact on the C2 vertebral bone is likely to have been the cause of a widespread neuronal-axonal histopathological damage at the spinal-medullary junction and caudal medulla oblongata that is compatible with a severe fatal respiratory dysfunction and dysregulation of the autonomic pathways subserving the control of blood pressure and cardiac activity.