Transplantation of a vascularized pedicle of hemisected spinal cord to establish spinal cord continuity after removal of a segment of the thoracic spinal cord: A proof‐of‐principle study in dogs

INTRODUCTION: Glial scar formation impedes nerve regeneration/reinnervation after spinal cord injury (SCI); therefore, removal of scar tissue is essential for SCI treatment. AIMS: To investigate whether removing a spinal cord and transplanting a vascularized pedicle of hemisected spinal cord from the spinal cord caudal to the transection can restore motor function, to aid in the treatment of future clinical spinal cord injuries. We developed a canine model. After removal of a 1‐cm segment of the thoracic (T10–T11) spinal cord in eight beagles, a vascularized pedicle of hemisected spinal cord from the first 1.5 cm of the spinal cord caudal to the transection (cut along the posterior median sulcus of the spinal cord) was transplanted to bridge the transected spinal cord in the presence of a fusogen (polyethylene glycol, PEG) in four of the eight dogs. We used various forms of imaging, electron microscopy, and histologic data to determine that after our transplantation of a vascular pedicled hemisection to bridge the transected spinal cord, electrical continuity across the spinal bridge was restored. RESULTS: Motor function was restored following our transplantation, as confirmed by the re‐establishment of anatomic continuity along with interfacial axonal sprouting. CONCLUSION: Taken together, our findings suggest that SCI patients—who have previously been thought to have irreversible damage and/or paralysis—may be treated effectively with similar operative techniques to re‐establish electrical and functional continuity following SCI.