30/04/2026
This is an anatomical model of a lumbar disc herniation, also called a slipped disc or herniated disc in the lower spine.
What you’re seeing:
The bone structures are two lumbar vertebrae, stacked with an intervertebral disc between them.
The gel-like material bulging out from the disc is the nucleus pulposus — the soft inner part of the disc that has pushed through the tougher outer ring [annulus fibrosus].
The yellow structure next to it is a spinal nerve root. You can see the red inflammation where the bulging disc is pressing against or irritating the nerve. That’s what causes the sharp, radiating pain, numbness, or tingling you get with sciatica.
In simple terms: The cushion between the spine bones has ruptured and is pinching the nerve.