What exactly is sciatica? According to Dorland's Medical Dictionary, sciatica "is a set of symptoms including pain that may be caused by general compression and/or irritation of one of five spinal nerve roots that give rise to each sciatic nerve, or by compression or irritation of the left or right or both sciatic nerves." The sciatic nerves are the largest nerves in the human body. There are only two of them, and one runs down the length of each leg. The top of the sciatic nerves are found in the lower back, or lumbar region of the spine. A common cause of sciatica is a herniated disc. A disc is an area of soft tissue located between the bones (or vertebrae) of the spine. A herniated disc is where the disc pins down the nerves in the spine. Sciatica generally originates in the lumbar (or lower) region of the spine.

While sciatica is not considered a condition in and of itself, it is considered a symptom of other injuries and most often occurs in people who have a history of lower back pain. Sciatic attacks can affect a person's body anywhere between the pelvis all the way to a person's toes and can be composed of severely sharp pains, dull aches, a burning sensation or a numbness and tingling.

Sciatica often affects people in their thirties and forties and can increase with age especially for those with chronic lower back pain. Once there is a flare-up of pain, bending forward or exertion can increase the pain and further the damage done to the sciatic nerve. In some cases, a physician may not be able to pinpoint the exact cause of the sciatica because many different injuries may cause sciatica. One flare up may be caused by auto accidents. When in a car accident, a person may be jostled around, pinned within the car, be the pedestrian hit by a car, or suffer severe injuries to the legs and lower back. If someone already suffers from lower back pain, sciatica may be a direct result of the pain inflicted on the legs and pelvis.

The job of the chiropractor when dealing with sciatica is not necessarily to give a history of how the sciatica became inflamed and irritated in the first place. The chiropractor's job is to help the body heal itself. Chiropractors use a non-invasive approach. Instead of surgery and poking around to find the cause of the sciatic nerve pain, chiropractors may utilize hot and cold therapies, ultrasound and spinal adjustments (commonly referred to as "manipulation").