There are many known and unknown causes of bulging discs in the intervertebral spaces of the spinal column. Bulging disc is a term usually reserved for minor herniations in which the disc structure remains completely intact.
Disc bulges are one of the most common of all spinal abnormalities and are most typically not symptomatic or problematic in any way. In some cases, a bulging intervertebral structure can press into the spinal cord, enacting symptomatic spinal stenosis or enter into the neuroforaminal space, enacting foraminal stenosis and possibly a pinched nerve. However, many times these diagnoses are made unfairly, since disc bulges may be near or even touching these neurological structures without enacting any symptoms whatsoever.
This treatise explores the usual causes behind intervertebral bulging.
Spinal degeneration is completely universal and expected in our species. We will all have varying degrees of degeneration, usually beginning to be noticeable in the 3rd generation of life, but sometimes may present structural evidence when we are younger or older.
The usual physical changes associated with normal deterioration of the spine include: degenerative disc disease and spinal arthritis, including osteophyte formation, degenerative endplate changes and facet joint arthritis.
Disc desiccation definitely contributes to bulging discs, as well as other possible occurrences, such as annular tears. The degenerative processes also facilitate full herniated discs and ruptured discs, as well. Most patients will demonstrate the most significant degenerative changes in the middle to lower cervical spinal levels and in the lower lumbar and lumbosacral spinal levels.
Some discs simply bulge for no reason at all. This is particularly true for patients who do not show remarkable degeneration and have never hurt their backs. These types of bulges are considered idiopathic; meaning of unknown origin.
A huge number of people have idiopathic disc pathologies, some of which may appear very significant on diagnostic imaging studies. Some of these conditions may be congenital, while others may be developmental. In most cases, these disc issues will not be painful, but a minority of intervertebral bulges may cause symptoms of varying intensities.
Back injury can certainly also cause discs to bulge, herniate or rupture spontaneously. The force of such injuries is great and is likely to enact pain for several days to several weeks. The pain is not necessarily from the disc issue specifically, but may be due to general trauma and soft tissue injury.
Even painful herniations due to injury should heal in a matter of weeks in most cases. The chances of a mild to moderate herniated disc injury causing chronic back or neck pain are low indeed.
Remember that a disc bulge is not inherently painful unto itself. Unless the bulge is impinging a neurological structure, such as a nerve root or the actual spinal cord, no symptoms are likely to come about from any bulging disc. However, if the bulge is a direct result of injury, this does not preclude pain due to general trauma, as previously noted above.
In reality, the only time it is critical to know exactly what caused a bulging disc is during civil litigation. However, even in these circumstances, it is very difficult to prove that a specific injurious event did in fact enact the bulge, unless comparative pre-injury testing is available which clearly shows no bulge right before the accident.
It is well known in medical and legal circles that disc bulges may have existed for years or decades prior to an accident, but never caused any pain. It is a good thing most jury members do not know this, or plaintiffs would be in for some real trouble when it comes to seeking monetary compensation for personal injuries.