Part of normal aging of the spine. Simply put wear and tear of the spinal disc. When a degenerative disc disease occurs, the disc loses its ability to cushion and maintain height between the vertebral bodies. That can lead to back pain and possibly radiculopathy (pain in the extremities). Diagnosis degenerative disc disease with MRI.
Treatments can consist of exercise, medication, physical therapy, medical procedure such as Epidural steroid injection or require spinal surgery.