title: Natural Progression of Spinal Cord Transection Injury and Reorganization of Neural Pathways.
abstract: The spinal cord injury (SCI) transection model accurately represents traumatic laceration and has been widely used to study the natural history and reorganization of neuropathways and plasticity in the central nervous system (CNS). This model is highly reproducible, which makes it ideal for studying the progression of injury as well as endogenous recovery and plasticity in the CNS. Five experimental groups of transection injury were designed: left hemitransection; right hemitransection; double hemitransection; complete transection injuries; and laminectomy-only control. We used somatosensory evoked potentials (SSEPs) as an objective electrophysiological assessment tool and motor behavior testing (Basso, Beattie, and Bresnahan [BBB] scoring) to functionally assess the neural pathways post-injury. Histological examinations were carried out to investigate the extent of injury and spinal cord morphological changes. Significant (p < 0.05) electrophysiological changes were observed and were verified by an increase in SSEP amplitude in somatosensory cortices for all four injury groups during days 4 and 7 post-injury. Degree of plasticity among the groups was distinguished by changes in SSEP amplitude and BBB scores. Our results support our previous published findings (using a contusive model of SCI), which shows that the reorganization of neuropathways and plasticity persist in time and are not transient phenomena. SSEPs are a reliable tool to assess the functionality of neural pathways and their projections to higher CNS structures such as the cortices. They enable us to determine residual function and the changes within the CNS post-injury and consistently track these events over time. The results from our study provide supporting evidence for the presence of neuronal network reorganization and plasticity in the CNS after transection SCI.
authors.affiliation: 1 Singapore Institute for Neurotechnology, National University of Singapore , Singapore .
authors.forename: Ashwati
authors.initials: A
authors.lastname: Vipin
authors.affiliation: 1 Singapore Institute for Neurotechnology, National University of Singapore , Singapore .
authors.forename: Xin Yuan
authors.initials: XY
authors.lastname: Thow
authors.affiliation: 2 Department of Electrical Engineering, American University of Sharjah , Sharjah, United Arab Emirates .
authors.forename: Hasan
authors.initials: H
authors.lastname: Mir
authors.affiliation: 3 Department of Computer Science and Engineering University of Oulu , Oulu, Finland .
authors.forename: Jukka
authors.initials: J
authors.lastname: Kortelainen
authors.affiliation: 4 Department of Orthopedic Surgery, National University of Singapore , Singapore .
authors.forename: Janani
authors.initials: J
authors.lastname: Manivannan
authors.affiliation: 2 Department of Electrical Engineering, American University of Sharjah , Sharjah, United Arab Emirates .
authors.forename: Hasan
authors.initials: H
authors.lastname: Al-Nashash
authors.affiliation: 4 Department of Orthopedic Surgery, National University of Singapore , Singapore .|5 Department of Biomedical Engineering, National University of Singapore , Singapore .|6 Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland.|7 Department of Neurology, Johns Hopkins University, Baltimore, Maryland.
authors.forename: Angelo H
authors.initials: AH
authors.lastname: All
mesh_terms: D000818:Animals; D005073:Evoked Potentials, Somatosensory / Q000502:physiology*; D005260:Female; D009043:Motor Activity / Q000502:physiology*; D009434:Neural Pathways / Q000502:physiology; D009473:Neuronal Plasticity / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013003:Somatosensory Cortex / Q000502:physiology*; D013119:Spinal Cord Injuries / Q000473:pathology / Q000503:physiopathology*; D013904:Thoracic Vertebrae
keywords: electrophysiology; neuroplasticity; traumatic spinal cord injury