To fuse or not to fuse that is the question

 
The intervertebral disc, or the shock absorber between the vertebral bodies, can be a source of significant back pain. In patients who have longstanding back pain that does not respond to conservative care, fusing the disc, or welding the two vertebral bodies together, have been traditional approaches. An interbody fusion, which means fusing the disc space between the vertebral bodies, is a traditional means for eliminating the back pain by stopping the motion between the two vertebral bodies.

 
But recently, spine surgeons have asked the question, can we eliminate the pain but preserve the motion? The artificial disk replacement (ADR) is placed between the vertebra to eliminate pain but preserve motion. Sounds good, but is it? Although the artificial disc has been available in Europe and utilized more commonly in the 1990s, it is considered experimental in the United States. Currently, experimental trials comparing the traditional fusion to the artificial disc are being performed in the United States to try to answer the question, is an artificial disc as good as, or better than fusing the same area?

 
The artificial disc must meet many demands – the materials must provide motion and stability and last under normal wear and tear circumstances of daily life. Since human beings come in different sizes and shapes, different sizes of artificial discs must accommodate these differences in human dimensions. Currently four different mechanical configurations of artificial discs are being evaluated: composite, hydraulic, elastic and mechanical. Which design will prove superior to the others awaits the longer tem follow-up of patients who have had the artificial disc implanted.

 
Under current circumstances, the artificial disc remains an experiment waiting for a conclusion.