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Why is there numbness in my legs? What is sciatica?


So a vertebral disc protrusion can cause numbness? But what is a disc?

sciatica spine numbness legs

When assessing why there is numbness in your legs, it is important to assess spinal structure.

Spinal discs are located in between the vertebrae. They play an important role in absorbing shock, supporting and accentuating many of the spinal movements.

Furthermore, they contain an inner, jelly like, portion of a disc. This is called the nucleus pulposus. Whilst the tough, outer layer is called the annulus fibrosus.

So what causes a disc protrusion/herniation?

Spinal disc herniations can occur for many reasons.

Firstly, of the main causes in incorrect posture or heavy lifting. When the spine moves in to a forward (flexed) position, additional body weight is placed on the front portion of the disc. This causes additional pressure in the front portion of the disc. Therefore, the nucleus will move in a posterior (backwards) direction. This creates pressure on the posterior portion of the annulus fibrosis. Importantly, if this is done with enough force, small tears may occur in the annulus. This may cause the disc to bulge out slightly. Known as a ‘disc bulge’. Furthermore, the spinal cord, and nerve roots are located very close behind the spinal disc. If the bulge is severe enough to push out beyond the boundaries of the vertebral body (and often in to the nearby nerve roots), it is known as a disc protrusion.

So what causes disc degeneration?

Another cause of disc protrusion/herniation is know as disc degeneration. This occurs when the discs lose some of the fluid that makes them spongy. Causing and reduction in height. This is often worse with age.

A gradual process of disc flattening and hardening occurs throughout one’s life. The overall process starts early and can even be seen in some imaging scans in early adulthood. This leads to easier disc bulging or cracking when pressure is applied to the discs. Importantly, any protrusions caused, again are likely to lead to nerve root compression. When a nerve root is compressed, pain is often felt along the path of the nerve. This is why it is common for individuals to suffer with referred pain in to the buttocks or legs.

A thank you note…

Finally, Pinnacle Posture thanks you for reading this blog post. We hope you liked it. Importantly, please share it via social media and direct it to those that it may help. After all, a reduction in pain, a chance to continue in a sport or even an eased concern can change someone’s world.


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