What Is a Discography?
by Nicole Berardoni M.D., Paul Lynch M.D., and Tory McJunkin M.D.
Discography is a diagnostic tool used to determine whether certain discs of the spine are the source of a patient’s neck or back pain. Low back pain affects approximately 80% of the general population at least sometime during their lifetime. It is also the fifth leading cause of physician visits, as well as the leading cause of work-related disability.
Discography has been used to diagnose the cause of low back and neck pain, especially when non-invasive imaging, such as magnetic resonance imaging (MRI), does not reveal abnormalities consistent with the pain symptoms (Wichman 2007). Discography is considered for patients who have disabling low back pain, neck pain, and arm or leg radiation pain when other conservative diagnostic methods and treatments have failed.
Anatomy of the Spine
Understanding the anatomy and physiological function of the spine is the key in evaluating a person with back pain. The bony spine is positioned so that individual vertebrae (bones of the spine) provide a flexible support structure while also protecting the spinal cord. Certain conditions that can produce chronic pain affecting the vertebrae include spinal stenosis, vertebral body fractures, osteoporosis, osteoarthritis, spondylolisthesis, neoplasms (primary vs. metastatic lesions), and infections. Separating each individual vertebrae are discs that act as cushions to minimize the impact that the spinal column receives. Since the discs are designed to be soft and provide support, they have a tendency to herniate posterior (backwards) through the outer disc segment and ligaments. Bulging and leaking discs often cause irritation to the adjacent nerves. Disc disease is one of the most common causes of chronic back pain and accounts for approximately 10% of all low back pain complaints. Disc disease may be acute, herniation resulting from trauma, or more commonly, chronic in nature. Degenerative disc disease is a process, which is due to a thinning and degeneration of the discs over time.
Before the procedure begins, your skin will be appropriately cleaned to decrease the risk of infection. A small needle with local anesthetic will then be injected into your skin to numb the area before a larger needle is inserted. A larger needle is then inserted through the anesthetized skin and is positioned near the outer layer of the disc. Fluoroscopy, real time X-ray, is used in order to assure proper placement of the needle. A contrast solution is injected into the disc, and your response to the injection is observed at different locations. If pain is experienced that is similar to your chronic pain condition, then it is possible that your doctor has located the source of your pain. This process is typically repeated at two additional levels. The procedure generally takes about 30 minutes to an hour. Your pain physician may instruct you to go for a CT exam directly after the discogram to better localize contrast dye spread.
Discography For Prolapsed DiscAlthough MRI is considered a very good method for showing disc abnormalities, it does not show direct causes of pain. A study in 2007 concluded that the use of discography is more effective than MRI for detecting intervertebral disc ruptures as well as other conditions (Montes Garcia 2007). Since discography is considered a minimally-invasive procedure, it is performed when your physician has a high suspicion that your disc may be the cause of your pain. Typically patients who undergo discography have not gotten satisfactory pain relief from other measures including medication, physical therapy, and modified activities. MRI and CT scans show anatomical dysfunctions, whereas discography is able to pinpoint the locations producing the pain. Sometimes abnormal discs found on MRI or CT scan can be completely asymptomatic and do not cause pain. It is well known that minimally-affected discs can produce severe pain and may not be treated accordingly based on imaging alone (MRI/CT scan).
As with all medications and interventions, there is always a risk of complications. Typically discography is considered low-risk with minimal complications. Although uncommon, discitis can be severe. Discitis is an infection of the disc and presents as pain. Other risks are bleeding, hematoma, headache and increased pain.
After the results from your discography are reviewed, your pain physician will devise a treatment plan that will increase your level of function as well as decrease or eliminate your pain. The doctors at Arizona Pain Specialists are board-certified in treating pain conditions like yours. A clinical researcher concluded in 2007 that discography is a useful imaging and pain evaluation tool in patients with chronic spinal pain and that, “at our current level of understanding, discography is thought of as the best tool to evaluate disc-related pain” (Buenaventura 2007). If you are suffering from chronic back pain that has been refractory to other treatments, contact Arizona Pain Specialists today to see if you can benefit from their innovative treatments.