With the introduction of total disc replacement (TDR) surgery, surgeons can offer their patients an alternative to spinal fusion surgery for the treatment of symptomatic degenerative disc disease (DDD). The TDR procedure is intended to relieve pain and preserve motion in the spine.

During both TDR surgery and spinal fusion surgery, the pain-generating disc is removed and the disc height is restored. During a fusion surgery, the spinal segment is stabilized with an implant and plate and/or rods and screws. Bone graft may be used to promote osseous fusion of the vertebrae.  Conversely, during a TDR surgery, an implant that allows motion is inserted into the disc space.

Both treatments are usually effective for relieving pain. However, preserving motion at the treated vertebral segment may enable the spine to restore its sagittal balance and maintain more natural mechanics after surgery than fusing the vertebral segment. This may potentially decelerate degeneration in adjacent levels in the spine.