Bulging disc causes can vary greatly, but aging – and the related changes the body endures – tends to be the main reason that disc bulges develop. Bulging discs typically occur in people aged 30 years or older and can lead to a number of symptoms and additional issues within the spinal column. But what exactly is a bulging disc and how does the condition develop in the first place? To answer this, it can be helpful to first have a clearer understanding of the spinal anatomy.
Anatomy of the Spine
The spine, which runs from the base of the skull to the buttocks, is made up of a long stack of vertebrae, as well as intervertebral discs, supportive muscles, ligaments, and other tissues. The column that is formed by these components serves to protect the spinal cord and provide various openings for its nerve roots to travel to the rest of the body. The spinal column is also responsible for supporting the upper body and providing us with the ability to bend, twist, turn, etc.
The intervertebral discs are located in between the vertebrae and serve as sponge-like cushions for the spine, absorbing various impacts as we go throughout each day. Each disc consists of cartilaginous cells within a matrix of water, collagen fibers, and protein. The outer wall, or the annulus fibrosus, is a tough band of fibers that surrounds a gelatinous inner disc material, known as the nucleus pulposus. The discs, along with the other components of the spine, allow us to have an enormous range of motion to bend, twist, and turn within several directional planes. A lifetime of such movements puts a lot of stress and pressure on the spine, particularly in the cervical (neck) and lumbar (lower back) regions.
Development of a Bulging Disc
As previously mentioned, aging is considered one of the main bulging disc causes. As we grow older, the intervertebral discs begin to lose a significant amount of water. This dehydration causes discs to become brittle instead of pliable. As the vertebrae above and below an affected disc continue to exert pressure on the disc material, the structural integrity of the annulus fibrosus covering can be compromised. The inner disc material may then shift outward and cause the weakened outer wall to expand past its normal boundary and into the spinal canal. While most cases of this condition are asymptomatic, a bulging disc sometimes causes compression of the spinal cord or a nerve root. If this occurs, pain at the site of compression can develop, as well as radiating pain, tingling, weakness, and numbness in the upper or lower extremities. An affected disc may also become painful in and of itself if the tiny nerves that feed into the disc are damaged or irritated as a result of a disc bulge or tear.
Other Bulging Disc Causes
Besides aging, other causes of the condition can include:
• Using tobacco products
• Traumatic injury
• Repetitive movements or motions
If a bulging disc causes symptoms to arise in a patient, a doctor may suggest a course of conservative (non-surgical) treatments to initially combat pain. Such methods usually include pain medication, physical therapy, and hot/cold therapy, among others. Treating a bulging disc with a surgical procedure is typically not recommended immediately after diagnosis. Doctors will usually only suggest surgery to patients whose symptoms have not responded to several weeks or months of conservative treatments.