Disc herniation is a condition involving the protrusion of the soft portion of the intervertebral disc resulting from a tear or injury in the outer fibrous ring. When the disc herniates, several nerves that pass along the area of protrusion may become trapped or impinged causing severe pain and discomfort. The torn intervertebral disc may also lead to inflammation contributing to further pain.
Disc herniation is commonly termed as slipped disc, but the mechanisms of the injury do not involve slipping of the disc because the intervertebral disc is fixed between the vertebrae and only the soft portion protrudes.
There are several causes of disc herniation including:
- Wear and tear injuries
Disc herniation is commonly caused by general wear and tear in the discs as a result of various activities. For instance, jobs that require constant squatting or sitting can lead to wearing of the protective tissues around the disc causing it to tear. When the spine is straight, the pressure inside the spine is equalized; however, when one sits or squats, the pressure increases by a ten-fold leading to continuous wear and tear injury. Jobs involving heavy lifting may also lead to disc herniation, but incorrect posture while lifting is actually the main cause and not the lifting alone. Lifting while bending at the waist is a common reason for disc herniation because the anterior side of the disc is usually compressed with this kind of position. The presence of chronic back pain can be an indication of wear and tear making the person more at risk for developing disc herniation.
- Direct physical trauma
Physical trauma is another cause of herniated disc. Falling for instance can cause direct pressure on the spine and intervertebral disc causing mild to severe tears depending on the extent of injury. Sudden twisting motions on the spine from work or leisure (sports) can also lead to such. Lastly, exposure of the back to vibration such as in the case of working with jackhammers can produce tiny tears on the discs overtime. Other injuries causing a direct blow on the spine can all lead to disc degeneration and protrusion.
Genetics was also seen as a factor for the development of disc herniation. Mutations in the genes THBS2 and MMP2, which are involved in the regulation of the extracellular matrix, were found to cause disc herniation in the lumbar area.
Aging is also a factor on the development of disc herniation. As we age, the disc losses some of its extracellular matrix or water component reducing its flexibility and increasing its risk for tearing. This condition is known as disc degeneration and without proper prevention; the disc may just be torn leading to protrusion in the disc.
Aside from these direct causes, disc herniation is also linked to certain lifestyle habits such as smoking, unhealthy diet, obesity, sedentary lifestyle and overall poor health because of their role in the weakening of the intervertebral discs. Smoking for example can release toxins in the body that can hasten disc degeneration.
With all these causes of disc herniation, the condition is clearly preventable. Employing good body mechanics, avoiding trauma, employing overall excellent lifestyle and the like may prevent the degeneration and protrusion of the disc.