The term “sciatica” is commonly used to describe pain traveling in the distribution of the sciatic nerve. Sciatica is a symptom caused by a disorder occurring in the lumbar spine. The sciatic nerve is the largest nerve in the human body, about the diameter of a finger. The sciatic nerve then runs vertically downward into the back of the thigh, behind the knee branching into the hamstring muscles (calf) and further downward to the foot.

Sciatic Symptoms 
Usually sciatica affects one side of the body. The pain may be dull, sharp, burning, or intermittent shocks of shooting pain beginning in the buttock traveling downward into the back or side of the thigh and/or leg. Sciatica then extends below the knee and may be felt in the feet. Sometimes symptoms include tingling and numbness. Sitting and trying to stand up may be painful and difficult. Coughing and sneezing may intensify the pain.

The Cause: Nerve Compression
The most common cause is a herniated disk in your back, although there are other causes as well. An MRI Scan of your lower back may help in making the diagnosis. Rarely is nerve damage permanent and paralysis is seldom a danger. Several different nerves can result in sciatica. A combination of a good assessment and studies

(x-rays, MRI’s and/or EMG/NCS) can help determine the exact nerve involved