Degenerative disc disease is not a disease but, rather, a term used to describe the normal changes that occur in spinal discs as we age. Spinal discs are soft, compressible jelly-like substances that separate the bones that make up the spine. These discs act as shock absorbers and allow the spine to bend, stretch and twist.
As we age, discs become dehydrated, causing them to lose volume and become less supportive, and make them more prone to injury. Degenerative disc disease can occur anywhere within the spine, but it most often occurs in the lower back (lumbar region) and neck (cervical region).