Spinal Nerve RootsSpinal NervesPeripheral Nervous System NeoplasmsNerve Compression SyndromesSpinal CordLumbosacral RegionRadiculopathyLumbar VertebraeForamen MagnumForamen Ovale, PatentNeuralgiaSpinal Cord InjuriesMagnetic Resonance ImagingInjections, SpinalSciatic NerveSciaticaPeripheral Nerve InjuriesLigationLumbosacral PlexusPeripheral NervesGanglia, SpinalHyperalgesiaForamen OvalePeripheral Nervous System DiseasesIntervertebral Disc DisplacementNerve FibersCauda EquinaNerve BlockSpinal CanalCervical VertebraeSpinal StenosisSpinal Cord NeoplasmsSacrumRats, Sprague-DawleyPainMyelographyPain MeasurementEpidural SpaceSpinal Cord CompressionPain ThresholdLaminectomySpinal Cord DiseasesOptic NerveSpinal DiseasesNerve RegenerationCervical PlexusHeart Septal Defects, AtrialTooth RootSpinal NeoplasmsMononeuropathiesRhizotomyLow Back PainDecompression, Surgical