Sciatica occurs when pressure is applied to the nerve and becomes tight (or feels like a pinch) and usually occurs due to pressure on the disc located in the spine. In addition to the disc, the nerve can also tighten the narrowing of the spinal canal, so-called spinal stenosis, can cause certain injuries such as; fractures of the femur or pelvis and the widening of the arteries (aneurysms).

It’s a coming fact that people with diabetes are more at risk of being affected by sciatica as long-term elevated levels of sugar (hyperglycemia) damage nerves.

When thinking about sciatica, it is important to have a clear understanding of the underlying medical cause, as they will affect the treatment and the actual causes of pain, as well as the treatment options for relieving acute symptoms.

Lumbar Herniated Disc

It occurs when the soft inner material of the disc leaks out the fibrous outer core and irritates or “pinches” the adjacent root nerve. Other terms used to indicate a herniated disc include; “slip disk”, “cracked disk”, “bulging disk”, “protruded disk” or “stretched nerve”. Sciatica is the most common cause of a lumbar disc herniation.

Degenerative disc disorder

While a certain degree of degeneration of the disc occurs as a natural part of the aging process, some (one or more) degenerate disc’s in the lower back, may also irritate the root of the nerve and cause sciatica. Degenerative disc disease is diagnosed when the weakened disc is weakened as a result in excessive micro-movements of the spine at the level, and inflammatory proteins become exposed inside the disc and irritate the root (or more) of the nerve in that area.


Lumbar spinal stenosis

This condition usually causes sciatica due to the narrowing of the spinal canal. Stenosis of the lumbar spine is associated with the natural aging process and is relatively common in adults over the age of 60. The condition commonly results as a combination of one or more of the following: enlarged joints, excessive growth of soft tissue and projections by placing pressure on the nerve root, causing pain of the sciatica. Lumbar spinal stenosis usually occurs with spinal arthritis, and arthritis can also cause or contribute to the symptoms of sciatica.

Piriformis Syndrome

The sciatica nerve can cause irritation as it flows below the piriform muscle in the buttocks. If the piriformis muscle irritates or invades the nervous root it can cause types of sciatica.

This is not the right lumbar radiculopathy, which is the clinical definition of the sciatica. However, since pain in the legs may feel the same as sciatica or radiculopathy, sometimes it is called a sci-fi.

Sciatica joint dysfunction

Irritation of the cranial joint, located at the base of the spine, can also irritate the L5 nerve, which lies on the top of the sacroiliac joint, causing sciatic pain. Again, this is not a real radiculopathy, but the pain in the legs may feel the same as the sciatica caused by nerve irritation.

Additional common causes of the sciatica:

  • Pregnancy – Changes which the body goes through during pregnancy, including weight gain, shifting the centre of gravity and hormonal changes, can cause sciatica during pregnancy.
  • Scar tissue – If scar tissue (also referred to as epidural fibrosis) is compressed into the root of the lumbar nerve, it can cause lesion.
  • Muscle Tension – In some cases, inflammation associated with lower muscle tension and/or muscle spasms may exert pressure on the root of the nerve and cause pain in the stomach.
  • Spinal Tumour – In rare cases, the spinal tumour can penetrate the root of the nerves in the lower back and cause the sciatica symptoms. It is possible that the tumour originates from the spine, but more often the spinal tumours develop as the cancer arises in the second part of the body (metastasized) and spreads to the spine, causing pain.
  • Infection – Although rare, infection that occurs in the lower back can affect the root nerve and cause sciatica.
  • Fracture – If a fracture occurs in the lumbar vertebrae, symptoms may present as sciatica. Most fractures occur due to serious trauma (such as a traffic accident or fall) or due to bone loss due to osteoporosis or other underlying condition.
  • Ankylosing spondylitis – This condition is characterised by chronic inflammation in and around the spine. Often the symptoms appear for the first time in the joints, causing sacroiliitis, and symptoms that present may include sciatica.
  • Other things that can aggravate back pain include; being overweight, not getting enough regular exercise, wearing high heels, sleeping on a mattress that is too soft or too hard.

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