How are results of lumbar fusion, and lumbar total disc replacement comparing?

The authors of a recent literature review felt that there was a correlation between fusion and the development of adjacent segment degeneration compared to total disc replacement. The authors also felt there was a stronger correlation between fusion and the development of adjacent segment disease compared to total joint replacement. Because the studies that were available to review were not high in quality, they could only make a weak recommendation for the use of total disc replacement versus fusion.