This procedure is also known as Total Disc Arthroplasty. Total disc replacement replaces a severely degenerated disc with one made of a prosthetic, or artificial one. The artificial version is designed to duplicate the function of a normal disc.
In traditional spine surgery, occasionally there is a need to "Fuse" the vertebrae together to obtain stability of the spine. Fusing the disc space eliminates movement of that segment and places more stress on the disc levels above & below the fusion. The added stress to these levels is thought to accelerate premature degeneration and pain of the nondegenerative discs. In addition, spinal fusion often requires a bone graft with spinal hardware and the need to wear a brace after surgery.
An artificial disc replacement avoids the need to fuse the vertebrae, thus preserving spinal mobility. This helps prevent additional stress to the levels above & below the fusion, avoids bone grafting/spinal hardware & the need to wear a brace postoperatively. All of these benefits allow early movement & reduced pain after surgery.