Spinal Cord DiseasesSpinal Cord InjuriesSpinal CordParaplegiaQuadriplegiaSpinal Cord CompressionRecovery of FunctionSpinal Cord NeoplasmsSpinal Cord IschemiaCervical VertebraeNerve RegenerationSpinal Cord RegenerationAutonomic DysreflexiaInjections, SpinalThoracic VertebraeParalysisWounds and InjuriesUrinary Bladder, NeurogenicMotor NeuronsLocomotionRats, Sprague-DawleyWheelchairsSpinal InjuriesContusionsElectric Stimulation TherapySpinal Nerve RootsAxonsSpinal NervesDisease Models, AnimalLaminectomyMyelitisBrain InjuriesMuscle Spasticity