Science today isn't the same as the science 2000 years ago was but some principles remain the same. The human knowledge constantly grows but with more knowledge there comes even more mysteries and unsolved questions, so science is always going forward.
Causes. The most common cause of a cervical herniated nucleus pulposus is gradual degeneration of the disc, attenuation (weakening) of the posterior annulus fibrosis, and subsequent protrusion of the nucleus pulposus into the spinal canal causing compression of the nerve root.
A needle is first inserted into the nucleus pulposus under local anesthesia. A small amount of the nucleus pulposus is vaporized with the laser energy. As a result there is a sharp decline in pressure within the disc and the herniation moves away from the nerve root.