The Skinny On Lumbar Artificial Disc Replacement

Effective treatment for recalcitrant degenerative disc disease (DDD) has been the holy grail of low back pain. It's not an easy problem to deal with. Replacing the degenerative intervertebral lumbar disc achieved FDA approval in 2004 with the SB Charite implant as the first one, and it was expected to be the holy grail for low back pain from DDD.

The theory was to replace the diseased or damaged disc with a prosthetic implant which would not only take away back pain, but also increase the height of the damaged disc area back to normal. This would then open up the areas where the nerve roots were coming out and potentially being pinched from the disc height being gone and subsequently indirectly causing a pinched nerve(s).

The implant is made of metal and polyethylene. The approach used to place the implant is done through the abdomen, and typically it's done in a retroperitoneal manner. This means the surgeon goes outside of the bowel cavity and just shifts it over during the approach. Once the front of the spine is reached, the big vessels are pulled out of the way so the spine surgeon may remove the damaged disc.

Once the disc is completely removed, the artificial disc is carefully placed, making sure to place it directly centered so that normal range of motion and loading can be achieved to try and replicate normal physiology and kinesiology of the new disc to what it's supposed to be with a native disc.

It's crucial to size the implants properly so they don't shift and "spit out". There are numerous styles of artificial discs now approved by the FDA, and there's also approval on one to implant at more than one level. So if there's degeneration at both L4-5 and L5-S1, the surgeon may work on both at the same time.

The results for artificial disc replacement have been so far the same as spinal fusion. All the FDA required is that the implant work just as well as the gold standard (spinal fusion) and not be inferior, and that's exactly what the artificial disc replacement did. It has not turned out to be the holy grail of spine surgery as hoped, but it does have its place in the treatment of degenerative disc disease.

As with any elective spine surgery, proper nonsurgical treatment should be attempted prior including physical therapy, pain management,and maybe chiropractic and/or spinal decompression treatment.