Sciatica refers to the pain one experiences due to the irritation or compression of nerve roots contributing to formation of Sciatic nerve. The sciatic nerve is the longest and widest nerve in the body, running from the lower back, down to the back of each leg. The pain can occur in the lower back and spread to the hips, buttocks and leg. Sciatica generally affects one side of the body. There are numerous causes of irritation of the sciatic nerve and sciatica.
Some of them are:
- Spinal Stenosis: The narrowing of the spinal canal caused by natural wear and tear of the vertebrae (individual bones in the spine protecting underlying nerves) of the spine is known as spinal stenosis. The narrowing may put pressure on the roots of the sciatic nerve, causing pain.
- Herniated Disc: A disc is made up of cartilage and acts as a cushion between vertebrae, allowing flexibility of the spine. A herniated or slipped disc occurs when a disc is temporarily pushed out of place, putting pressure on the sciatic nerve.
- Spondylolisthesis: It is a condition where one of the lower vertebrae slips forward over another. This also causes a collapse of the disc space between both, causing the nerve to get pinched. This may cause sciatica.
- Piriformis Syndrome: Piriformis is a muscle found deep inside the buttocks, which connects the lower spine to the upper thighbone, running directly over the sciatic nerve. Spasming of this muscle can pressurize the sciatic nerve, triggering symptoms of sciatica.
- Sacroilitis: Sacroillac joints are the place where the lower spine meets the pelvis and inflammation of one or both of these joints causes sacroilitis. This can give rise to symptoms of sciatica as it causes pain in the lower back, buttocks and legs.
- Spinal tumors: Very rarely, tumors growing inside or along the spine may put pressure on the sciatic nerve.
- Infection or injury: Muscle inflammation, infections, fractures or any other spinal injury may lead to irritation or compression of the sciatic nerve.
- Pregnancy: Pregnant women may suffer from sciatica due to weight gain, expansion of the uterus or increased fluid retention or other changes occurring in the body, which put pressure on the sciatic nerve.
- Other causes: Osteoarthritis and fractures caused by osteoporosis may also affect the sciatic nerve, producing symptoms of sciatica.