Axonal integrity predicts cortical reorganisation following cervical injury

Traumatic spinal cord injury disrupts the communication pathways between the brain and spinal cord, leading to clinical impairment. This study investigates how the structural integrity of the corticospinal tract (CST), a key white matter pathway, relates to spinal cord area and brain reorganization in individuals with cervical spinal cord injury. The study uses multimodal MRI to assess axonal integrity, spinal cord area, and brain activity during motor tasks. By examining the relationships between these measures, the researchers aim to understand how microstructural changes in the CST are linked to macroscopic changes in the spinal cord and functional changes in the brain's motor cortex. The findings reveal significant differences in the CST of SCI subjects compared to controls, with microstructural changes predicting both increased brain activity in the leg area and reduced spinal cord area. These results suggest that trauma-related axonal degeneration and demyelination are connected to cortical motor reorganization and spinal cord macrostructure.

• 1
  Diffusion tensor imaging showed significant differences in the CST of SCI subjects compared to controls in areas such as the pyramids, internal capsule, cerebral peduncle, and hand area.
• 2
  Microstructural white matter changes in the left pyramid predicted increased task-related responses in the left M1 leg area, indicating a link between axonal integrity and cortical reorganization.
• 3
  Changes in the cerebral peduncle were predicted by reduced cord area, suggesting a relationship between microstructural damage in the brain and macrostructural atrophy in the spinal cord.