a woman suffering from sciatica

Sciatica Causes

Sciatica is not so much its own diagnosis as it is a symptom of another medical problem. The sciatic nerve begins near the base of the spine and extends all the way down the back of each leg. Sciatica occurs when something damages or applies pressure to the sciatic nerve; multiple medical problems can cause this to occur.

Disc Problems

A lumbar herniated disc (also referred to as a slipped, ruptured, protruding, or bulging disc) is one of the most common causes of sciatica. This problem occurs when a spinal disc wears down, allowing the gel-like center of the disc to leak out. The herniated disc itself pinches the nerves, and the gel from inside the disc causes nerve damage. Degenerative disc disease is another possible cause of sciatica; this condition is similar to the herniated disc, except that it is caused more by old age and genetics but still features nerve irritation due to the contents of the damaged disc.

Spinal Stenosis

Stenosis occurs primarily in older people and is caused by the narrowing of the spinal canal or spinal column openings. Such narrowing causes sciatica and back pain due to the shrinking canal and the simultaneous swelling of bones and ligaments in the spine. Stenosis patients often report that sitting down feels significantly better than standing, perhaps due to the lessening of spinal compression that occurs when people are seated.

Isthmic Spondylolisthesis

Spondylolisthesis occurs when one vertebra slips forward over another vertebra. Sciatica results from the nerve compression caused by this slipping forward, as is muscle pain and discomfort in the area of the slipped vertebra. This condition is generally caused by a degenerative disease, such as arthritis, but it may also be caused by trauma and stress fractures.

Piriformis Syndrome

The piriformis muscle runs from the base of the spine to the thigh bone and helps the hips rotate. Sometimes this muscle can experience spasms, leading to the compression of the sciatic nerve. This compression causes pain, numbness, and tingling up the back of the leg in addition to the pain in the buttocks from the piriformis muscle.

Spinal Tumors

Spinal tumors are fairly rare, but the formation of benign or malignant tumors in the spinal column can cause sciatica due to nerve compression. The formation of tumors in the spinal column is generally the result of there being a tumor in an adjacent organ, such as a breast, kidney, or lung. The back pain that results from these tumors generally does not diminish with rest; the pain might even be worse at night than during the day.


Much of the treatment for sciatica hinges on properly diagnosing the underlying issue that’s causing it. Recommended treatment methods may include reduced activity, no heavy activity for a month and a half after the pain began, and limited exercise after two to three weeks. A doctor might also recommend receiving corticosteroid injections, but recent studies have suggested that short-term benefits of these shots may be minimal and long-term benefits are likely nonexistent.

Last Updated: November 21, 2016