Key takeaways
- Sciatica is pain, numbness, tingling or weakness running down the leg from an irritated nerve in the lower back.
- The nerves exiting between L4 and S1 are the ones most often involved.
- Bulging and herniated discs are the most common causes, but arthritis, disc thinning and synovial cysts can do it too.
- The right treatment depends on what is actually compressing the nerve.
Sciatica is an interesting condition, because so many people believe they have it and not all of them do. The most common description I hear is simply, "I have leg pain." Sciatica does cause leg pain, but the condition is more specific than that. To understand it, it helps to start with the anatomy of the lower back.
The anatomy
Your spine holds you upright and protects the spinal cord, which runs from your brain toward your tailbone inside the spinal canal. The lower back (lumbar spine) is made up of five vertebrae that connect to the sacrum.
Between each pair of vertebrae is a disc, made of cartilage that is flexible enough to let you bend and twist, yet strong enough to carry your weight. Each vertebra-disc-vertebra unit forms an opening on each side, called a foramen, where a nerve exits the spine. These nerves are where sciatica begins.
What is sciatica?
Focus on the lowest segments, between L4 and S1. The nerves exiting at L4-L5 and L5-S1 are the ones most often affected. After they leave the spine, they join with others to form the sciatic nerve, the largest nerve in the body.
When one of these nerve roots is compressed or "pinched," you can feel pain, numbness, tingling or weakness travelling down the leg. That is sciatica. It can affect one leg or both. The next question is why the nerve is compressed.
What compresses the nerve?
The most common causes are bulging and herniated discs. Other conditions can do it too:
- Disc degeneration and disc thinning
- Osteoarthritis and bone spurs
- Synovial cysts
- Spinal stenosis
- Tight muscles in the buttock, such as the piriformis
When a nerve is compressed, it interferes with the signals travelling between the brain and the leg, which is what produces the symptoms.
How is sciatica treated?
The best treatment depends on what is compressing the nerve. If the cause is a disc problem, creating more space between the vertebrae, so the openings the nerves pass through get larger, is often the most direct approach.
Other options include anti-inflammatory injections, and in some cases surgery to remove disc or bone material pressing on the nerve. For many disc-related cases, though, non-surgical spinal decompression such as the DRX9000 is an excellent conservative option. Decompression gently separates the vertebrae, which creates negative pressure within the disc. That can help draw disc material away from the nerve and improve the disc's hydration over time.
Do you have sciatica?
Now that you know what sciatica is, you can start to ask whether it fits what you're feeling. The most important step is finding the actual cause, because that determines the treatment. You don't have to keep living with it.
Seek emergency care right away if leg pain comes with loss of bladder or bowel control, numbness in the groin area, or rapidly worsening leg weakness.