Intervertebral Disc DegenerationIntervertebral DiscIntervertebral Disc DisplacementSpinal DiseasesLumbar VertebraeFibrocartilageSpinal OsteophytosisCompressive StrengthAggrecansWeight-BearingCollagen Type IIMagnetic Resonance ImagingStress, MechanicalProteoglycansBiomechanical PhenomenaTooth FracturesCadaverDisease Models, AnimalSpineDiskectomyCervical VertebraeLumbosacral RegionFemurTensile StrengthLow Back PainCollagen Type IXMaterials TestingSpinal FusionIntervertebral Disc ChemolysisCells, CulturedNotochordThoracic VertebraeSpondylolisthesisSacrumRetinal DegenerationMacular DegenerationNerve DegenerationTibiaSpinal StenosisScoliosisChymopapainLordosisDiscitisBack PainGlycosaminoglycansSpinal Cord InjuriesExtracellular Matrix ProteinsLaminectomy