Pain comes from inflammation and irritation of local nerve endings. Before suggesting a treatment, doctors do a special test to be certain that the problem is a degenerated disc at a specific level. During the so-called discogram, dye is injected into the suspect disc. If the dye spreads diffusely, the pressures within the disc measure lower than normal and the procedure elicits the same pain the patient typically feels, a treatment at that level stands a good chance of improving symptoms. Discs at other levels are tested also to be sure that the problem is limited.
Limited damage is treated more successfully than widespread damage.
Privett's problem was confined to one severely narrowed disc, which put pressure on the sciatic nerve and triggered his leg symptoms. At the time, his choices were to either continue living with the pain or have the degenerated disc removed and the vertebrae fused together. In traditional surgery, the back is opened and bone from the spinal column is taken off to expose the problem disc. The disc is then removed and bone grafts, usually from the hip crest, take its space. Titanium screws and rods provide additional structural support.