In the strictest sense of the word, the so-called aging process of the spine develops as a natural age-related response to the dislocation of the tissues, which occurs from adulthood. These often clinically subtle degenerative changes are able to alter the mechanical properties and the anatomical structures of the spine. This dysfunction may entail a destabilization and sometimes lead to spinal instability. The various degenerative injuries to the elements stabilizing the spine, including the vertebra, the spinal motion segment and muscles, may cause segment injuries that are likely to affect the flexibility and the stability of the spine, thereby altering its curvatures. Destabilization worsens progressively as the anatomic structures keep deteriorating. Degenerative lesions and destabilization can endure and experience à transition into degenerative spondylolisthesis and scoliosis. But more often than not a spinal ankylosis—i.e. amending of the degenerative process by restabilization-can be established. Spinal ankylosis can develop in the aftermath of a destabilization but in most cases it does not develop secondary to any destabilization.