Sciatica

• Sciatica is nerve pain from irritation of the sciatic nerve.
• The sciatic nerve is the largest nerve in the body.
• Sciatica pain is typically felt from the low back to behind the thigh and radiating down below the knee.
• Treatments for sciatica depend on the underlying cause and the severity of the pain.

Sciatica is pain in the lower extremity resulting from irritation of the sciatic nerve. The pain of sciatica is typically felt from the low back (lumbar area) to behind the thigh and radiating down below the knee. The sciatic nerve is the largest nerve in the body and begins from nerve roots in the lumbar spinal cord in the low back and extends through the buttock area to send nerve endings down the lower limb. The pain of sciatica is sometimes referred to as sciatic nerve pain.

While sciatica is most commonly a result of a lumbar disc herniation directly pressing on the nerve, any cause of irritation or inflammation of the sciatic nerve can reproduce the symptoms of sciatica. This irritation of nerves as a result of an abnormal intervertebral disc is referred to as radiculopathy. Aside from a pinched nerve from a disc, other causes of sciatica include irritation of the nerve from adjacent bone, tumors, muscle, internal bleeding, infections, injury, and other causes. Sometimes sciatica can occur because of irritation of the sciatic nerve during pregnancy.

Picture of a herniated disc, a common cause of sciatica