The spine consists of small bones known as vertebrae. Between these vertebrae are structures called discs that are intended to provide cushioning and support to the structures of the spine. Over time, these discs can rupture, irritating nearby nerves and leaving vertebrae unsupported. When this happens to multiple discs due to general wear-and-tear, the condition is known as degenerative disc disease.
It is not uncommon for physicians to recommend spinal fusion as a form of treatment for degenerative disc disease. However, many patients can be helped with physical therapy as a non-operative form of treatment before attempting surgery. Because surgery can be expensive and invasive (or may not be an option depending on health and age factors), the American Physical Therapy Association recommends first trying physical therapy before taking a more invasive approach to treatment.