Methods to promote reanimation and rehabilitation of forelimb function after spinal cord injury

Abstract

Spinal cord injury is a devastating condition that can severely limit motor and sensory function and make an individual completely dependent on others for care. The effects of spinal cord injury are debilitating, and available treatments have limited effect. Impaired signal transduction, increased inhibitory molecules near the injury site, and cell damage all contribute to poor recovery from spinal cord injury. The following chapters describe experiments that aim to address these three obstacles to restore movement to paralyzed limbs. Electrical stimulation treatment can induce movements of paralyzed limbs, but these treatments have not yet restored normal motor function. A user-controlled stimulation system may improve the effects of spinal cord stimulation by allowing the user to trigger movements relevant to a particular task. In addition, supplementary treatments that mitigate the biological reaction to spinal cord injury may be necessary to achieve lasting improvements in motor function. Chondroitinase treatment can introduce a period of plasticity in the adult central nervous system and promote sprouting of descending fibers in the injured spinal cord. Electrical stimulation may help to guide sprouting fibers toward motor neuron targets to circumvent the injury. Stem cell treatment can provide cells to replace or help rehabilitate injured cells, and electrical stimulation may help to guide these new cells toward the formation of beneficial motor circuits. This thesis demonstrates the potential of a brain-controlled spinal stimulation device to restore task-related movements, present a novel behavioral task to evaluate motor recovery in a rat model of spinal cord injury, and investigate the utility of chondroitinase and stem cell treatments in restoring function after spinal cord injury.