Publication / Source: Neurology Central
Authors: Christopher S. Ahuja & Michael Fehlings (both University of Toronto, ON, Canada)
One of the most devastating diseases of the central nervous system is traumatic spinal cord injury (SCI). These injuries produce dramatic physical impairments which limit independency, create social and vocational barriers, and cause financial hardship for patients. With over 1.4 million North Americans affected and direct lifetime costs as high as $1.1–$4.6 million per patient, there is a critical need for effective therapies in this field .
The evolving standard of care increasingly recognizes the concept of “time is spine” and the need for expedient medical and surgical intervention analogous to the “time is brain” paradigm in stroke. Timely care can have profound impacts on a patient’s long-term independence, morbidity (e.g. neurologic, respiratory, etc.) and overall mortality. This requires early recognition of the injury, rapid transfer to specialized centers and effective delivery of the evidence-based therapies discussed below .
The primary traumatic event injures neurons and glia, but it also initiates a secondary injury cascade which can be as devastating as the primary insult. Injury to the cord microvasculature is particularly important as it leads to early ischemia and hemorrhage. Over the subsequent hours, the compromised blood-spinal cord barrier also allows an influx of vasoactive peptides, proinflammatory cytokines and peripheral inflammatory cells. Over days to weeks, regions adjacent to the injury epicenter are affected by the nearby cord swelling, proapoptotic signaling, cytotoxic molecule release and uncontrolled inflammation. This results in an extension of the initial injury through the susceptible spinal cord ‘penumbra’ .