Diagnosis of degenerative disc disease typically begins with a medical history. The physician will be particularly interested in the history of a patient’s back pain and may ask questions such as:

• When did the back pain begin?
• What causes the pain to increase?
• Is there a family history of back pain?

The physician will perform a physical examination, paying special attention to the areas where pain occurs. A pain assessment may be conducted. 

The physician may also order various imaging tests to better assess the condition of the intervertebral discs. These tests can include:

• X-ray. Uses radioactive materials to record images of bone. The physician will look for a decrease in the space between the discs, bone spurs, hardening (sclerosis) of nerve bundles, enlargement (hypertrophy) of the vertebral facets (articulating joints between vertebrae) and instability during flexion (bending) or extension (straightening) of limbs.

The main method of diagnosing a painful degenerative disc is an x-ray procedure called discogram.  This is a test in which a physician injects contrast with a small needle into the damaged disc under the guidance of fluoroscopy, which is a real-time x-ray.  If the patient is experiencing pain from that damaged disc, then the pressure of the contrast that is injected into the disc will reproduce the patient’s pain.  A CAT scan may be done afterward to obtain better anatomical image of the disc.

• CAT scan (computed axial tomography). A noninvasive or minimally invasive test that uses multiple computer images, taken from different angles, to create three-dimensional images of body structures. It can be used to identify tumors, herniated discs or other conditions that compress nerve roots. A myelogram (injecting contrast into the spinal canal) can be done prior to the CAT scan to identify precise spinal anatomy and dysfunction.

• MRI (magnetic resonance imaging). Uses magnetic waves to create computer-generated images. MRIs can reveal abnormalities with soft tissues, such as nerves or ligaments. They can also help reveal loss of water in a disc, facet joint hypertrophy, narrowing of the spinal canal (stenosis) or a herniated disc.