Lumbar disc herniation & sciatica

What it is

Each disc in the spine has a tough outer ring and a softer centre. When the outer ring tears, some of that centre can push out and press against a nerve root as it leaves the spinal canal. That pressure — and the inflammation that comes with it — is what produces sciatica.

Herniations are common, and a great many are found incidentally on scans of people with no symptoms at all. What matters is whether the herniation matches the pattern of pain you actually have.

What it feels like

• Pain travelling from the buttock down the back or side of the leg, often below the knee.
• Numbness or pins and needles in a specific band of the leg or foot.
• Weakness — a foot that drags or catches, or difficulty rising onto the toes or heel.
• Leg pain that is worse than the back pain, and worse with sitting, coughing, or sneezing.

How it is assessed

Your symptoms and examination help identify which nerve may be affected. An MRI may be used to confirm the location of a disc herniation when the result will guide treatment.

Disc changes are common on scans, including in people without pain. Your scan needs to be interpreted alongside your symptoms and examination.

Treatment

The majority of disc herniations improve without surgery. The fragment shrinks over weeks to months and the inflammation settles. Initial management is time, activity modification, physiotherapy, and appropriate pain control, sometimes with a targeted injection to settle a severe flare.

Surgery — usually a microdiscectomy, or an endoscopic decompression in selected cases — is considered when severe leg pain persists despite adequate conservative care, or earlier if there is significant or progressive weakness.