Sciatica is irritation of the sciatic nerve. The sciatic nerve begins from the lower spine on either side. It travels deep in the pelvis to the lower buttocks. From there, it passes along the back of each upper leg and divides at the knee into branches that go to the feet.

Sciatic Nerve Pain
Sciatica Nerve Pain
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Anything that causes irritation or puts pressure on the sciatic nerve can cause sciatica, including:

  • Herniated disk (or slipped disk)—the cushions between the bones of your spine bulge out of place and press on the nerve as it exits the spinal column
  • Arthritis in the lower back
  • Spinal stenosis —narrowing of the spinal canal in the lumbar area
  • Spondylolisthesis —slippage of a bone in the lower back
  • Piriformis syndrome— spasm of piriformis muscle
  • In rare cases:
    • Cauda equina syndrome —nerve roots at the base of the spinal cord are compressed
    • Fracture in the back
    • Benign or malignant tumors
    • Infections
    • Metabolic problems like diabetes