Spinal cord injury not only damages the site of the lesion but also impacts the brain and spinal cord, disrupting both motor and sensory functions. Using advanced magnetic resonance techniques, Simon Schading-Sassenhausen, Maryam Seif, and colleagues at Balgrist University Hospital, University of Zurich, revealed signs of nerve cell loss in the motor cortex as well as the spinal cord. Their findings provide valuable insights for monitoring SCI-related changes and designing future treatments.
Spinal cord injury is often seen as a local problem, but its effects extend much further. It disrupts networks that connect the brain and spinal cord, influencing both movement planning in the brain and motor control in the lower spine. To investigate these effects, researchers compared people with chronic spinal cord injury to healthy participants, focusing on the primary motor cortex in the brain and the lumbar cord enlargement in the spine.
The scans revealed clear signs of damage. Structurally, the lumbar cord had shrunk in both gray and white matter. Metabolically, levels of N-acetylaspartate relative to creatine – a marker of healthy neurons – were reduced not only in the lumbar cord but also in the motor cortex. The loss was strongest in the spinal cord but also visible in the brain, showing that spinal injury leads to widespread nerve cell stress and degeneration.
These findings provide evidence that injury triggers a chain reaction along the motor system: neurons above the lesion in the brain degenerate, while neurons below the lesion also deteriorate. Importantly, metabolic markers were able to detect subtle changes that standard scans might miss. This makes them promising tools for monitoring neurodegeneration and testing new treatments. By showing how damage spreads across the motor system, the study helps explain lasting symptoms and points toward better strategies for recovery.
Reference: Schading-Sassenhausen, S., A. Lebret, K. Şimşek, Gut P, Imhof S, Zörner B, Kreis R, Freund P, Seif M. 2025. Metabolic and Structural Alterations in the Motor System Following Spinal Cord Injury: An In-Vivo 1H-MR Spectroscopy Investigation. Journal of Neuroscience Research. 2025; 103(7) https://doi.org/10.1002/jnr.70071.
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