Sciatica refers to the symptoms of pain, numbness, tingling, burning sensation or weakness that originate in the lower back, radiate through the buttock, and continue down the back of the thigh, leg and foot. Sciatica occurs when there is compression, inflammation or injury to the sciatic nerve or to its (spinal nerve) roots.
This type of pain that radiates along the course of a particular nerve root is called radicular pain. Depending on which nerve root is affected, different areas of the leg may exhibit symptoms.