Spinal Nerve RootsSpinal NervesSpinal CordPeripheral Nervous System NeoplasmsNerve Compression SyndromesLumbosacral RegionRadiculopathyLumbar VertebraeNeuralgiaAnterior Horn CellsMotor NeuronsSpinal Cord InjuriesGanglia, SpinalInjections, SpinalMagnetic Resonance ImagingSciatic NerveSciaticaPeripheral Nerve InjuriesLigationPeripheral NervesLumbosacral Plexusp-AminoazobenzeneHyperalgesiaAxonsPeripheral Nervous System DiseasesNerve FibersCauda EquinaIntervertebral Disc DisplacementNerve BlockHedgehog ProteinsSpinal CanalNeurons, AfferentSpinal Cord NeoplasmsRats, Sprague-DawleySpinal StenosisCervical VertebraePainSemaphorin-3ASacrumChick EmbryoPain MeasurementInterneuronsMyelographyOligodendrogliaNerve Tissue ProteinsPain ThresholdEpidural SpaceNerve Growth FactorsOptic NerveSpinal DiseasesNerve RegenerationSpinal Cord DiseasesSpinal Cord CompressionLaminectomyCervical PlexusMononeuropathiesRhizotomy