Between the neck and hips are 24 vertebral, between each vertebra is a disc that allows motion, acts as a shock absorber to the spine, and allows room for nerves to exit the spine. 90% of all spinal related pain is a result of problems with the vertebral disc, and most of these spinal problems are associated with a form of disc degeneration or weakening of the disc.
The other 10% of low back pain results in problems with the facet joints in the vertebra and all facet joint problems are also related to problems with the disc.
Vertebral discs are like a jelly donut, the outside part is a thick cartilage called the annulus, the inside is a jelly called the nucleus. As people age, the discs in their spine begin to wear and tear. Poor posture, incorrect movement and bending, and injuries, even from years earlier, can also weaken and tear the annulus.
If the annulus is damaged or the jelly-like nucleus dries out, the disc becomes unstable causing back and neck pain. If the disc becomes herniated, the nucleus breaks through the annulus compressing the nerves in the spinal canal also causing extreme pain.