Sciatica refers to pain in a lower extremity caused by irritation of a spinal nerve in your lower lumbar (lower back) region.  It’s commonly caused by a herniated lumbar disc, but may also occur with degenerative arthritic changes of the spine or, less commonly, with irritation of the sciatic nerve outside the spine.

Spinal nerve irritation may cause pain, loss of normal sensation, loss of muscle strength or any combination of these symptoms.  The pain is usually quite specific, occurring in a thin, band-like distribution from the lower back to the thigh, leg and foot.  It may come on gradually over time or rapidly after an acute injury.  The discomfort may vary from a mild tingling sensation in the foot to sharp, searing pains that shoot down the leg.

People who do a lot of heavy lifting, both young and old, are at risk for sciatica, as are older people with arthritis.  Sciatica in a younger person typically occurs from a herniated disc which pushes on the nerve or releases inflammatory chemicals that irritate the nerve.  In older people, sciatica may occur because of disc degeneration, the abnormal movement of one vertebral body over another, arthritis of the small joints in the back of the spine or thickening of the ligaments of the spine.  Or it may occur because of a combination of all of these things.