Adults suffering from pain, loss of function, and poor quality of life have three basic treatment options: conservative care and rehabilitation, spinal fusion, or the newer option of disc replacement. In order to find out how to advise their patients, surgeons from The Netherlands conducted an extensive survey of the published studies comparing these three approaches.
Current clinical practice seems to be moving away from spinal fusion and more toward lumbar disc replacement for symptomatic degenerative disc disease. The implants were first invented and designed to help with the problem of adjacent spinal disease that often occurs at the level above or below a fused segment.
But do they really protect the spine as intended? That’s one question that needs to be answered. They are expensive and long-term results are limited. So before surgeons shift completely from fusion to disc replacement, it’s a good idea to take a look at the current evidence.
After an extensive search on-line, the authors found seven studies that compared results of disc replacement, fusion, or rehabilitation. Combining all the patients in all seven studies, there was a total of 1301 people included. Only one of those studies really looked at rehabilitation.
Analysis of findings showed that patients improved no matter what type of treatment was applied. Patient satisfaction was greater in the group who had a total disc replacement. As intended, these implants did allow patients more natural motion.
But using a five-point criteria for assessing these studies, they found all had low quality evidence. None of the studies looked at subsequent adjacent segment disease, which is the main reason the implants were developed in the first place. The follow-up was two years or less, so long-term results aren’t really available. And many of the studies are funded by disc manufacturers, so there is a need for unbiased research without conflicts of interest.
The authors suggest strongly to orthopedic surgeons: be prudent in your use of disc replacements. Watch the reported results with a critical eye. Until high-quality studies with long-term results are available, it should not be assumed that “newer is better.” In other words, this new direction away from spinal fusion toward disc replacement hasn’t been adequately proven as the best approach.