LaminectomySpinal Cord CompressionDecompression, SurgicalSpinal StenosisLumbar VertebraeLigamentum FlavumCervical VertebraeThoracic VertebraeEpidural SpaceArachnoiditisDura MaterSpinal CanalSpinal Cord DiseasesSpinal Cord NeoplasmsSpinal NeoplasmsCauda EquinaMyelographySpinal OsteophytosisIntervertebral Disc DisplacementSpinal FusionLumbosacral Region