normal lumbar disc. disc protrusion. disc extrusion. disc sequestion. labeled

anatomical anatomy annulus arthrosis artwork back backage background black blue bulging degeneration disc doc exercise herniated illustration intervertebral lower lumbar medical medicine nerve nucleus operation orthopedist osteoarthritic osteoarthritis osteophytes pain pinched prolapse prolapsed pulposus root ruptured slipped spinal spine spondylophytes spondylosis stenosis treatment vertebra