Internal Disc Derangement

Internal Disc Disruption (IDD) is a common cause of disabling low back pain in a substantial number of young, healthy adults. From outward appearances the disc appears to be normal yet pain persists.

 

IDD is often found in young adults with a history of trauma. They present with severe pain that is usually central in the lower back. The symptoms are of chronic duration and typically worse with any loading of the disc and/or activities that increase the intradiscal pressure. Such activities often include bending, lifting, sitting and, sometimes changes in posture.

Unlike disc herniations however, this pain is not the result of disc compression upon the nerve root. In most IDD patients the pain does not usually radiate into either extremity past the knee to the foot. Typically, these patients have no “hard/classic” neurological findings. In other words, there generally is no weakness or sensory loss, no loss of deep tendon reflexes or root tension signs.

However, what we find is that internally the disc has sustained tearing in the outer annular fibers that surround the inner nuclear material. These tears, referred to as ‘radial’ tears, weaken the disc and create an irritation of the sensitive nerve fibers within the disc itself.

In the lower diagram you will note that the nerve roots demonstrated in yellow have not been affected, but the inner sinusoidal nerves (represented by small yellow dots) have now become inflamed (represented in red) and are producing severe pain and discomfort.


The Normal Disc

Disc with radial tear in IDD


Diagnosis:

The diagnosis of IDD is often elusive for many physicians. Frequently the patient has been treated for other suspected ‘most likely’ causes, and the treatments have not helped. If IDD is suspected, proper imaging studies must be completed to assist in the diagnosis.

At the Lordex Spine Institute if your doctor suspects you may be suffering from IDD, we will routinely recommend than a special type of MRI imaging study be performed to assist us with arriving at a proper diagnosis.

This examination is called a “Gadolinium enhanced MRI” study. Basically, a liquid is injected into the bloodstream and when the MRI study of the disc is performed, the ‘uptake’ of the gadolinium can pinpoint what is referred to as a “high Intensity zone” or HIZ.

In the MRI images show below, the image on the left is without the use of Gadolinium and we cannot see the actual injury within the disc. In the image on the right, we see how the Gadolinium “uptake” demonstrates the radial tear within the disc.


The “Gold Standard” of diagnostic studies for Internal Disc Derangement (IDD) is the Discogram. This is a minimally invasive procedure during which a needle is inserted into the disc itself and identifies the actual injury. Medically, a Discogram is the only current diagnostic procedure with wide acceptance.

However, discograms carry a degree of risk that need to be considered by the patient. There is the possiblity of further aggravating the injury itself as well as the risk of potential infection.

It is the policy of the Lordex Spine Institute to always use the least invasive diagnostic procedures possible, hence our protocol to have gadolinium enhanced MRI studies done first.

Should the enhanced MRI study be negative or inconclusive and the doctor still strongly suspect a diagnosis of IDD, recommendation for discogram may follow on a case by case basis.

As always, the final decision is made by the patient with the assistance of the doctor. Please do not hestitate to ask further questions if you suspect you may have IDD or concerns you wish to discuss.

Call today for your Complimentary Consultation with Dr. Tunick  503-684-9698