The first lumbar artificial disc, Charite, was approved for use by the FDA in 2004, and the Synthes Pro Disc L was approved in August 2006. The first cervical artificial disc, Synthes ProDisc c, was approved in 2007, and the first two level artificial disc LDR Mobi-C was approved in August 2013.
The advantage of an artificial disc is the preservation of motion. Lumbar and Cervical Artificial Disc Replacement has the same safety as a fusion surgery, and the recovery from the disc replacement is somewhat faster. Current evidence supports that artificial discs put less stress on the adjacent un-operated discs above and below. By the artificial disc placing less stress on their neighbors, the evidence supports that these un-operated adjacent discs will wear out less often as with a fusion.
One disadvantage of an artificial disc is unhealthy facet joints. If your disc is replaced with an artificial one, and the remaining two facet joints are painful, then you will continue to have pain. Prior to considering artificial disc surgery it is important for us to carefully review all the diagnostic studies and symptoms of your facet joints, and maximize the chance of your surgery succeeding.
Another disadvantage of artificial disc replacement is obtaining insurance approval. Several insurance carriers consider artificial disc surgery experimental, and will not approve their use.
There are several conditions that may prevent you from receiving a disc replacement. These include spondylolisthesis (the slipping of one vertebral body across a lower one), osteoporosis, vertebral body fracture, allergy to metal in the device, spinal tumor, spinal infection, and morbid obesity.
The surgical treatment of both neck (cervical) and low back (lumbar) symptoms may include either a fusion or artificial disc replacement. With artificial disc replacement, pain relief is brought about by removal of the painful disc and motion is maintained with the use of a prosthetic implant made of metal plates with a plastic middle bearing. This is more similar in theory to the artificial hip, knee, and shoulder joints that orthopedic surgeons have been using for more than 35 years to maintain motion and relieve the pain of arthritic extremity joints. However, there is a significant difference in that only one of the three spine joints that are present at each vertebral level is being replaced, whereas in a hip or knee joint, the total joint is replaced. Since each spine level has three joints, and the artificial disc only replaces one, the remaining two facets joints have to be healthy for you to have relief of your symptoms after artificial disc surgery. Fusion surgery brings about symptom relief by taking all three spine joints (disc and two facet joints) and using bone graft to stimulate them all to weld together with bone so that they will never move again. The fusion with the bone graft works more reliably when metal instrumentation is inserted at the same time.
Fusion surgery has the advantage of addressing the source of pain in all three joints: the disc and both facets. When the facet joints are arthritic, they cannot be replaced, and the best surgical choice may be a fusion. Minimally invasive fusion surgery today is a much easier recovery today that previous open surgery techniques. Fusion surgery in the neck and low back brings excellent symptom improvement and return to activities to many.
Fusion surgery has the disadvantage taking away motion, and adding stress to the next adjacent level. The literature reports that at 10 years about 25% of people with a fusion will have a problem at the next level. Remember 75% do not have a problem at the next level at ten years. New next generation minimally invasive lumbar fusion surgeries have less surgical muscle injury, and are likely to have less adjacent level problems.