Long-Term Benefits of Cervical Artificial Disc Technology Now AvailableIt's been 10 years since the first artificial disc was implanted in the cervical spine (neck). That event took place in Europe and quickly caught on in the United States. Now we have the four- and six-year results from a multicenter study looking at patients with degenerative disc disease who were treated with the Bryan Cervical Disc Prosthesis. The Bryan implant is made by a well-known company (Medtronic).
Anyone who is thinking about having a disc replacement in the cervical spine will be interested in the outcomes from this study. Everyone in the study had radiculopathy (nerve pain down the arm) or myelopathy (pressure on the spinal cord). The underlying problem was usually a disc protrusion or herniation. Most of the 89 patients involved had a single-level disc replacement. But a few (nine) had implants placed at two levels. Conservative (nonoperative) care was tried first but without success. Cervical disc replacement is a fairly new procedure; so understandably, it's not the first treatment choice for patients with these kinds of problems.
So, how successful has it been for these patients so far? Early results were reported as very positive after the first two years. The researchers have continued recording any adverse responses as well as any out right failures. X-rays were used to view the neck, discs, and motion at each involved level. The patients filled out several valid and reliable surveys to indicate how well they are doing (motion, function, neck and arm pain or other neurologic symptoms).
Now after six years, the results have been tallied once again. There was a high incidence of adverse events -- things like pain in the neck and arm (shoulder to wrist), numbness and tingling in the arm, and hoarseness of the voice. A few odd events were reported such as low back pain and a soft tissue tumor in the neck. Those problems weren't likely caused by the implant but all complications are being investigated. The real area of interest (used as a measure of success or failure of the implants) was the number of second surgeries (reoperations).
Any time the device migrated (moved or shifted), put pressure on the spinal cord, or had to be removed for any reason, it was counted as a failure. Once removed, the neck was fused rather than trying another disc replacement. Some patients had a second surgery but it wasn't to remove the implant or correct problems related to the first procedure. These additional surgeries were to treat disc problems at other levels in the cervical spine. Overall, the number of second surgeries was low and the success rate reported as 93.9 per cent.
Comparing the results after six years with the early two-year outcomes, it looks like most patients were still doing well. Any reports of pain or discomfort at the end of two years were even better after six years. There were some changes in sensation noted around the end of the fourth year. No one was quite sure what that was all about or why it resolved over time, so it's something they will continue to investigate in future studies.
By continuing to follow this group for a full 10 years, it will be possible to observe any late complications and/or late surgical reoperations. Since all patients receiving a disc replacement hope to keep it for the rest of their lives, these long-term studies are important. Surgeons will continue to compare results of disc replacement against the more traditional approach to this problem (fusion).
Although disc replacement allows continued motion at the involved segment, no one wants to face serious problems with this procedure if they can be avoided. And, if in the end, motion is lost, then perhaps a fusion is still the best way to go. These are all things researchers are looking at and will continue to follow for the next 10 years at least.
Jan Goffin, MD, PhD, et al. A Clinical Analysis of 4- and 6-Year Follow-up Results After Cervical Disc Replacement Surgery Using Bryan Cervical Disc Prosthesis. A Clinical Article. In Journal of Neurosurgery: Spine. March 2010. Vol. 12. No. 3. Pp. 261-269.
|*Disclaimer:* The information contained herein is compiled from a variety of sources. It may not be complete or timely. It does not cover all diseases, physical conditions, ailments or treatments. The information should NOT be used in place of visit with your healthcare provider, nor should you disregard the advice of your health care provider because of any information you read in this topic.|
|All content provided by eORTHOPOD® is a registered trademark of Medical Multimedia Group, L.L.C.. Content is the sole property of Medical Multimedia Group, LLC and used herein by permission.|