Degenerative Disc Disease (DDD)

The terms degenerative disc disease (DDD), internal disc disruption syndrome (IDDS), and discogenic low back pain are often used to identify the presentation of low back pain stemming from a degenerated or injured intervertebral disc. These overlapping terms can be confusing. Perhaps the most authentic of the three is discogenic low back pain; basically, low back pain from an unhappy, abnormal lumbar intervertebral disc.

Even if we agree to use discogenic low back pain to describe all cases of pain generated from the intervertebral disc, it is still important to understand what is meant by the terms degenerative disc disease (DDD) or internal disc disruption syndrome (IDDS). Clinically, the back pain that you would experience from either condition is similar. However, your physician’s interpretation of your condition may affect what treatment options you will be offered for your back condition. (see Intradiscal Modulation)

MRI of the lumbar spine. Sagittal T2 image showing DDD at L5-S1. Note the loss of white signal (dehydration), loss of disc height, and inflammatory endplate changes (orange arrow pointing to white signal in L5 vertebral body).

The term degenerative disc disease may be inaccurate. Degenerative disc disease (DDD) is a common condition in aging adults. Our intervertebral discs serve as shock absorbers for the spine, and as we age they gradually dry out, losing strength and resiliency. These changes are gradual in most people. In fact, most people do not know they have degenerative disc disease. Only a portion of the general population actually becomes symptomatic from their degenerated discs.

The most helpful investigation to screen for this condition in an MRI (magnetic resonance imaging) study. Common findings consistent with DDD include:

Disc bulging
Loss of hydration (loss of white signal from center of disc)
Decreased disc height (flattening of disc)
Endplate changes – or changes to the vertebral bone above and below the disc (e.g. inflammation, marrow replacement, bony sclerosis)

Internal Disc Disruption Syndrome (IDDS)

Some patients may have very painful intervertebral discs despite minimal degenerative changes on their radiological studies. Just because your MRI was deemed “normal” by your doctor does NOT always mean that your back pain is not coming from problems within that very disc.

What the MRI does not show are discrete tears within or through the fibrous rings of connective tissue (annulus fibrosus) inside the disc. This can lead to irritation of nerve endings within this fibrous ring, resulting in back pain. (leave out ‘neck’) This condition is called “Internal Disc Disruption Syndrome (IDDS)”. Clinically, the back pain that you would experience from either IDDS or DDD is similar.

Fig. 1 Cross-section of normal disc anatomy. Note the annular rings (green) around the central nucleus (pink)

Fig. 2 Cross-section of an abnormal disc demonstrating concentric (white arrows) and radial (red arrow) tears in the annulus.

Symptoms

As discussed above, disc degeneration is not usually a clinical problem; it is part of the normal aging process. Approximately 50% of pain-free adults people walking the streets today will show clear abnormalities on their MRI, despite having no back pain issues whatsoever!

That being said, some unlucky individuals may develop chronic, mechanical low back pain originating from one or more intervertebral discs. Symptoms may vary considerably, however, the average patient with a painful disc will experience back pain that is aggravated by sitting, prolonged standing, bending forward, lifting and twisting. Partial relief is often found with lying down on your back and the use of adequate lumbar support. Other patients will describe the sensation of a weakening of their abdominal and lumbar musculature despite efforts to maintain their “core” strength through exercise. Driving and flying can become intolerable.

Diagnosis

After reviewing your MRI, listening to your history and performing a proper physical exam, your physician may form a strong suspicion that you are suffering from discogenic back pain. However, there is no way for your physician to be 100% certain that your back or neck pain originates from the intervertebral disc(s) in your spine from this clinical assessment, alone.

In specific cases you may be recommended for a test called discography to confirm the diagnosis. This test involves injecting contrast dye into the affected disc (or discs) to stimulate the inside of this potentially painful anatomical structure. Because this diagnostic procedure can be uncomfortable it is only performed to crystallize your diagnosis priorto undergoing specific treatment such as intradiscal modulation or surgery.

Illustration of discography. Note the cottonball appearance of the x-ray contrast in the “normal” intervertebral disc (above) and the wide spread distribution in the “degenerated” disc (below).

Most likely, your physician will rule out the other most common causes of back or neck pain, as a first step. E.g. A common source of back or neck pain is the small joints of your spine, called the facet joints (“z-joints”, “zygapophyseal joints”). Another common source of low back pain that may mimic discogenic pain is the sacroiliac joint. Once (if?) these other possible diagnoses are ruled out, a discogram may be performed to confirm the original diagnosis, with confidence.

Non-operative Treatment

There is no cookie-cutter approach to the treatment of a painful degenerative disc. The initial management typically consists of a non-surgical treatment plan utilizing a combination of treatments over an 8 to 12 week period:

Exercise prescription
Appropriate anti-inflammatory medication
Spinal Injections
Lifestyle modification
Ergonomic assessment and modification

Intradiscal Procedures

If your pain fails to improve with your initial treatment plan, you may be a candidate for an intradiscal modulation procedure. There are three types of minimally invasive intradiscal modulation procedures discussed in interventional spine pain management:

Thermal:
Intradiscal Electrothermal Therapy (IDET)
Posterior Radiofrequency Ablation (PRFA)
Biacuplasty
Chemical:
Intradiscal Methylene Blue (MB)
Intradiscal corticosteroids
Biological:
Fibrin Sealant: See Orthobiologics

There are very strict criteria determine whether a patient is a candidate for any of the above intradiscal procedures. It is not an option for all patients with discogenic back pain. You should discuss the specific criteria with your specialist physician. (see Intradiscal Modulation)

Surgical Treatment

If symptoms of discogenic back pain persist despite these non-operative treatments, Dr. Helper will help you determine if you are a surgical candidate. Surgical treatment for discogenic back pain is controversial. The surgical options generally include disc arthroplasty (disc replacement) or fusion. To determine if you are a surgical candidate, Dr. Helper may recommend further testing, including:

An updated MRI or CT Scan
Awake provocative discography
If applicable, Dr. Helper will help guide you to the most appropriate spine surgeon for your condition.