I've clearly made up my mind to have a disc replacement in my neck instead of a fusion. Now I'm surfing the web for any information I can find about the best kind of implant device to use. Do you have any information that might help me?
Not all patients with neck and/or arm pain from degenerative disc disease are good candidates for disc replacement. So the first step is always to have a surgeon evaluate your situation and advise you regarding the best treatment. Since you have it in mind to pursue a disc replacement, we are assuming you have the go-ahead from your surgeon.
That being said, sometimes the choice of a specific implant (total disc replacement or TDR) is really up to the surgeon. Experience with a particular TDR, technical skill, and overall expertise may be more important than the specific type of device used.
Placing the implant with the right angle and position is very important in restoring normal kinematics (spinal motion). Even a small amount of asymmetry or being off center can result in uneven wear and tear on the spinal joints or increased load on the segment above or below the implant.
Studies show that adjacent segment disease (ASD) is a problem after spinal surgery of this type. ASD refers to degeneration or breakdown of disc and/or vertebra above or below a spinal segment that has been fused. ASD can also occur after a disc has been replaced with an implant. And although very limited at this time, there isn't strong evidence that one implant is better than another for preventing ASD.
In fact, there was a recent systematic review published with information you might find helpful. The researchers evaluated all the studies published so far comparing adjacent segment disease (ASD) after fusion and disc replacement. A subset of their study was to look at the difference in outcomes between two implant devices (Bryan and ProDisc-C).
Their conclusions? First and foremost, studies comparing fusion versus disc replacement for cervical spine degenerative disc disease come up short. Many of these studies are conducted by companies that make the disc replacement devices. So there is a clear need for independent research. Independent means the research isn't carried out by (or paid for) by companies manufacturing these implants.
There is a moderate amount of evidence that no difference exists in short-term or medium-length follow-up results between fusion and disc replacement. In other words, the development of adjacent segment disease is about the same after either type of treatment. But no specific recommendation can be made to guide the selection of treatment without further studies with stronger evidence.
Likewise, they were unable to offer any firm conclusions about the value or benefit of one disc replacement system over another. There just isn't enough evidence or enough strong evidence to make such a statement. They do point out that it is difficult to perform a blind study, which would be more objective.
In a blind study, the outcomes would be measured without patients or physicians knowing who had which treatment. Since X-rays are one of the main ways to assess results, it is always clear what type of treatment was provided each patient.
It is good to gather as much information as you can before making a final decision about surgery of this type. We hope what we have provided will help you formulate questions for your surgeon. Ultimately, your decision will be made in consultation with the surgeon and your resaerch will provide you with the answers you need.