There were only five patients in the study. Although the results were moderately successful, this procedure is not available for everyone just yet. Much more study is needed. But scientists are cautiously optimistic that this type of transplantation is possible.

The patients receiving donor tissue were followed for up to five years. X-rays at the end of that time showed some mild loss of disc space. This suggests there are some degenerative changes occurring in the donated segments.

One patient had a natural neck fusion. The two vertebrae adjacent (next to) the transplanted disc formed a solid union. MRI showed the disc signal was still preserved but there was no movement at that level.

It's still too early to tell what the long-term effects of transplanted discs may be. Animal studies have been successful enough to conduct trials in humans. There are still many questions about how long the discs will remain alive and if the mechanical stability will last.