Lumbar disc extrusions, a common spinal condition, occur when the inner nucleus of a spinal disc escapes through the outer annulus layer, potentially impinging on nearby nerves. To comprehend this phenomenon, it’s crucial to grasp how medical imaging, particularly X-rays, illuminates these structures, while acknowledging its limitations compared to MRI. We’ll delve into the process of disc extrusion, contrasting it with herniation, bulge, and protrusion. Additionally, we’ll explore the significance of disc annulus fissures and introduce Discseel as a non-surgical treatment option.
X-ray Visibility of Lumbar Disc Extrusions:
X-rays, utilizing electromagnetic radiation, excel at visualizing bone structures due to their high density. However, soft tissues like intervertebral discs pose a challenge due to their low density, resulting in poor visibility. In X-rays, disc spaces appear as dark lines, and abnormalities such as extrusions may manifest as irregularities or decreased disc height. Nevertheless, the subtle nature of soft tissue details limits X-ray’s efficacy in diagnosing disc pathology alone.
Limitations of X-ray Imaging:
X-rays offer a static snapshot of skeletal structures, lacking the ability to capture dynamic or soft tissue changes comprehensively. Consequently, they may miss vital information crucial for diagnosing spinal conditions, especially those involving soft tissues like discs. Moreover, X-rays expose patients to ionizing radiation, limiting their frequency of use, particularly in vulnerable populations.
Comparing X-ray to MRI:
In contrast, Magnetic Resonance Imaging (MRI) employs magnetic fields to generate detailed images of soft tissues, including spinal discs, with unparalleled clarity. Unlike X-rays, MRI provides multiplanar views, enabling precise assessment of disc morphology, hydration, and any associated pathology. Its non-invasive nature and lack of ionizing radiation make MRI the preferred modality for evaluating spinal disorders.
Disc Herniation vs. Disc Extrusion
If a disc fissure is large enough, the nucleus pulposus material in the center of the disc can escape outside the disc. The distinction between a herniation and an extrusion is dependent on the shape of the nucleus pulposus material that has escaped. If the width of the material at its tip is narrower than at its base then it is referred to as a herniation. If the width of the material at its tip is wider than at its base then it is referred to as an extrusion. Therefore, having a disc herniation may not feel different than having a disc extrusion. Although these two terms are sometimes used interchangeably, they have different meanings regarding how discs appear on an MRI even though they may not feel different to a person who has the disc abnormality.
Disc Protrusion vs. Disc Bulge
As more disc fissures form and progress, the disc annulus is weakened causing it to be displaced beyond its typical boundaries. If the disc annulus displacement involves less than 90 degrees (<25%) of the disc circumference then it is called a disc PROTRUSION, however, if the disc displacement involves greater than 90 degrees (>25%) of the disc circumference then it is called a disc BULGE. The distinction between these two terms literally depends on how much of the disc wall is displaced. Therefore, having a disc protrusion may not feel different than having a disc bulge. Although these two terms are sometimes used interchangeably, they have different meanings regarding how discs appear on an MRI even though they may not feel different to a person who has the disc abnormality.
A Need for Consistent Terminology
An effort is being made for all Radiologists (doctors who specialize in interpreting MRIs, x-rays, etc.) to use standardized vocabulary in their MRI reports, especially when it comes to the spine MRIs. The difference between a herniation and an extrusion as well as the difference between a protrusion and a bulge allows the Radiologist to communicate the appearance of the disc abnormality. An effort is also being made to avoid terms like “slipped disc” and “ruptured disc”.
In order for a disc protrusion, disc bulge, disc herniation or a disc extrusion to be present, there must be disc annulus fissures present to cause weakening of the disc wall. When disc annulus fissures extend long enough to travel through the entire thickness of the disc annulus, then certain molecules can leak out of the center of the disc (nucleus pulposus), through the disc annulus fissures and into the epidural space, which is where spinal nerves are located. These leaking molecules trigger a series of chemical reactions that result in inflammation, which is irritating to nerve tissue. This inflammatory process can cause nerve pain symptoms in the corresponding leg even without any MRI evidence of a compressed “pinched” nerve.
Disc fissures will never repair on their own because the disc lacks a blood supply sufficient for healing. For the same lack of blood supply reason, disc fissures cannot be surgically sewn successfully. If left untreated, disc fissures predictably progress and eventually reach the outermost portion of the disc annulus, causing them to leak over time. The center of the disc (nucleus pulposus) eventually loses enough of its fluid content causing the disc to decrease in height and eventually collapse. This process is called Degenerative Disc Disease. On MRI these discs appear dark and flat compared to discs that are not degenerating.
Learn About Discseel®
The only way to solve this problem is to seal the disc fissures, ideally before the disc starts to collapse. Because this cannot be accomplished surgically, an ideal non-surgical alternative is Discseel®. This new non-surgical procedure injects the healing protein fibrin into each tear to immediately seal the disc. Over the following months, the fibrin promotes disc tissue growth, sealing and healing previously torn discs. There are several other injection procedures that attempt to treat disc pain (stem cells, PRP, etc.), but they are all limited by the fact that they cannot immediately seal the disc tears and these products end up leaking back out of the disc, which minimizes their benefit. Learn more about Discseel® at RegenerativeSpineAndJoint.com and find out how your low back disc protrusions and disc bulges can be successfully treated non-surgically.