Your spine is built for movement, but it also has to be stable. In essence, it’s this duality that confuses many physicians and patients and often leads to a back fusion, which stops movement in patients with degenerative or painful back issues, such as degenerative disc disease, and spinal stenosis (arthritis that’s putting pressure on nerves). But fusing any level of your spine with hardware can overload other areas of the spine, weakening and damaging those areas as well and causing pain after back fusion. This is called adjacent segment disease (ASD).
The Basic Anatomy of the Back
To understand ASD, you first need to understand the basic anatomy of the back (watch my brief video above for illustrations of the spinal structures). The back is made up of 24 movable vertebrae, or back bones, that stack one of top of the other, stretching from the neck to the lower back. A disc sits between each vertebra, and the vertebrae come together in the back at the facet joint. Protected between the vertebrae and the facet joints, there is a canal that houses the spinal cord, a big bundle of nerves that transmits feeling and tells our muscles what to do.
This is all held together by ligaments and kept stable by a series of muscles called multifidus, and the spinal column has natural opposing curves to distribute our weight and provide stability.
Back Fusion Permanently “Locks” the Vertebrae, Leading to ASD
Fusion surgery is done when vertebrae become so unstable that movement affects the nerves or causes pain. A back fusion is a surgery that uses hardware and screws to permanently “lock” together two or more vertebrae, and the purpose is to indeed make the damaged section of spine immovable. Fusion surgeries are lengthy, risky, and painful.
The fact that a fusion takes a structure in our body that gives us flexibility in movement and makes a portion of it immovable is a big enough problem, but it gets worse. This forced lack of movement puts more stress on and overloads the vertebrae above and below the fused levels. This can cause significant pain after back fusion as bone spurs at those levels and degenerative arthritis in the facet joints can press on the nerves and lead to adjacent segment disease (ASD), that predictable breakdown in the neighboring unfused levels.
So I Have Pain After Back Fusion Due to ASD, Should I Get Another Fusion?
NO! The solution is certainly NOT to get another fusion. More fusions will simply create more problems and more ASD and more fusions—a never-ending cycle. Spinal fusion is not worth it.
In a New England Journal of Medicine study on back and neck fusion that I shared on the blog a couple of weeks ago, researchers concluded that fusion surgeries didn’t improve outcomes at two or five years after surgery!
So fusion patients are being exposed to higher surgical risks and are developing ASD (commonly enough that the condition was given a name—adjacent segment disease), and yet this high-level study supports the lack of any clinical value in the fusion surgery. I’ve personally seen more patients harmed than helped over the last two decades by back fusion surgery. So the fact that surgeons continue to do them is perplexing.
Even more concerning than the studies we do have is the studies we don’t have: we don’t have any high-level evidence that spinal fusions are effective to treat pain. There are low-level studies published by spine surgeons and fusion-device manufacturers that seem to show that fusion works. However, this doesn’t fit with the clinical experience of anyone who sees so many patients struggling with significant pain after back fusion. And it certainly doesn’t mesh with high-level studies such as the one in my article above.
ASD Isn’t the Only Problem Post-Fusion Patients Experience
While I have seen a few patients who have a severe instability that can only benefit from a fusion, it’s rare. More often than not, post-fusion patients require revision surgeries; need ongoing narcotics following surgery; experience complications due to their surgery, such as irrevocable damage to the multifidus muscle; and spend a lot of money on a serious surgery providing very little to no long-term returns. With results this poor and so much research showing reasons not to, why would you want to treat your ASD with another fusion?
In addition, in spinal stenosis, for example, spinal fusions are far more dangerous due to their complication rates than the decompression surgery they’ve gradually added to over the last 10–20 years.
ASD Can Be Treated Without Fusion Surgery
Unfortunately, we can’t reverse the original fusion, but in my experience, the resulting ASD can be treated with advanced Interventional Orthopedics. This involves precise placement of your body’s own stem cells and platelets to help the ligaments, muscles, joints, and nerves above and below the back fusion.
The upshot? Your spine is made for movement, and when part of it is forced into immobility, adjacent parts of your spine will compensate and try to keep you moving. Unfortunately, this stresses and overloads those vertebrae and can cause pain after back fusion and lead to adjacent segment disease. Once you’ve developed ASD, opt out of additional fusion surgery, and consider stem cells and/or platelet injections to treat your ASD.