Sciatica (which is sometimes misspelled as "psyatica" or "syatica") is caused by irritation of one of the large sciatic nerves (one on each side), and is a pain that usually begins in the buttock region and may travel down the leg, possibly all the way to the foot. The sciatic nerve is composed of smaller nerve roots that arise from the lower part of the lumbar spine and the sacral area. The nerve roots form the righ and left sciatic nerves in the lower pelvis, and then each sciatic nerve travels down the thigh and splits in half below the knee, with the halves then extending the rest of the way down the leg.

While there are several possible causes of sciatica, by far the most common source of sciatic nerve irritation is a bulging or herniated disc in the lower lumbar spine. A damaged disc may bulge into the opening where one of the nerve roots exits the spine on it's way to join other nerve roots as part of the sciatic nerve. The bulging disc may create direct nerve pressure, and/or may trigger inflammation and swelling, which can also cause pressure on the nerve. When this occurs, pain and other symptoms may be felt part along the course of the sciatic nerve, starting in the buttock area and possibly running down the leg, sometimes all the way to the foot.

Besides disc bulges, spinal openings for nerves may be narrowed by bone spurs or other bone formations related to spinal degeneration. In some cases, sciatica may result from direct trauma to the nerve after it exits the pelvis, such as what can happen if there is a direct impact or hard pressure applied in the lower buttock region. Rare sources of sciatica can include spinal tumors, which can compress sciatic nerve roots as they exit the spine. Another rare cause of sciatica is a cyst or tumor that compresses the sciatic nerve in the hip or knee area.

Not every buttock or leg pain that people think is sciatica is acutually sciatica. True sciatica (sciatic nerve irritation) is usually felt mostly in the back of the leg (not the front or side of the leg). Symptoms of true sciatica are described by various people as stabbing, burning, tingling, numbness/heaviness, or like an electric shock. But even if symptoms seem like sciatica, they are not always due to actual irritation of the sciatic nerve.

One common condition that closely mimics sciatica is caused by knots of contraction called trigger points in a muscle called the piriformis. The piriformis muscles are located on either side of the lower buttock area, running from the upper thigh bone to the edge of the sacrum (the triangular pelvic bone that is at the base of the spine). In addition to causing symptoms that mimic sciatica, tightness in the piriformis muscle may also cause true sciatic irritation, because the sciatic nerve actually runs through the center of the piriformis muscle in some people, and can be compressed by excessive muscle contraction.

Trigger points in other muscles in the buttocks and upper thigh can cause referred pain in the side of the leg that may be mistaken for sciatica as well. It should be kept in mind that true sciatica and piriformis syndrome are associated with symptoms that are primarily felt in the back of the leg. If symptoms are in the front or side of the leg, there's a good chance that the problem is not sciatica.

Treatment of sciatica is usually associated with treating a bulging disc. The first line of treatment is usually an attempt to reduce inflammation to reduce pressure on the nerve bymeans of oral medications. For more powerful anti-inflammatory effects, spinal injections with steroids like cortisone may be used. A variety of other types of treatment may also be used, such as physical therapy, massage, chiropractic or osteopathic spinal manipulation, acupuncture, or one of the newest forms of treatment, spinal decompression. In some situations, surgery may be recommended as a last resort.

In the majority of cases, an episode of sciatica will resolve even without any treatment within a period of several weeks, but due to the intensity of pain, most patients will not wait for it to go away on its own and seek out treatment. Unfortunately, due to misconceptions by doctors and patients alike regarding the nature of sciatica, the necessary steps to prevent a return of sciatica are usually not taken. So, even though most people do recover from a bout of sciatica, nearly all will eventually have problems again at some point. Even sciatica sufferers initially treated successfully with surgery will often have future problems with sciatica.

The good news is that with awareness of how to manage sciatica and a little bit of effort dedicated to prevention, most people can avoid ongoing long-term sciatica problems. The challenge is simply to making people aware of the necessity of a "management" versus "cure" approach to sciatica and getting them to follow-through with preventive exercises and other self-care techniques.