The actual incidence of herniated discs can not be accurately determined, being the vast majority go unnoticed and undetected, since they do not cause any pain or related neurological symptoms whatsoever. Medical science can only talk about the incidence of known and estimated herniated discs which represent a theorized fraction of their occurrence in the general population. Although we know far more about bulging discs than ever before, there is still a vast amount that is either unknown or completely misunderstood.
This article covers the topic of herniated disc occurrence in terms of anatomical location and frequency.
Of the herniated discs which are discovered through diagnostic imaging, most occur in the lumbar spine or at the lumbosacral junction.
Herniated discs at L5/S1 and L4/L5 are the most prevalent locations for abnormal disc pathologies in the human spine. L3/L4 is also a typical intervertebral level for herniations, although less common than the previously mentioned sites.
While it is possible for herniations to exist virtually anywhere in the spinal column, they are far less prevalent in the thoracic spine.
Many herniated discs are discovered in connection to a back, neck or sciatica pain complaint. Sometimes, the herniation corresponds to the area of the painful expression and sometimes it does not. Occasionally, the herniation turns out to be the definitive source of pain or neurological dysfunction, but more often, it is completely innocent of blame and coincidental to the symptoms experienced. In some cases, the disc is a possible contributor, but not a definitive causative factor. Other herniated discs are found by chance during testing for some unrelated health matter.
Statistics demonstrate that there is no proof that herniations are inherently painful and there is plenty of proof showing that disc bulges exist in huge numbers in the general population and do not enact any pain. Most people simply do not know they are there, since they are not problematic and are not related to any reported health concern.
We will likely never know just how common herniations truly are, unless every human on this planet decides to have spinal MRI studies performed routinely. However, using population samples of patients whose herniations were discovered randomly and not in relation to a back pain complaint, the incidence must be incredible.
Patients must understand that many times, the suspected source of their herniated discs, such as accidents or injuries may or may not be accurate. Many herniations have existed in the spines of countless people without their knowledge, maybe for decades.
If by chance the person hurts themselves in any way and winds up getting a spinal MRI, these herniations will be found and almost universally blamed on the recent occurrence. In many cases, the degenerative endplate changes and other tell-tale markers clearly show that the herniations predate the perceived injury.
This evidence is almost always arbitrarily ignored, especially when it comes to civil personal injury litigation.