As with any surgery, complications with spinal fusion surgery are possible. As a general rule of thumb, the more invasive a surgery is, the higher the risk of complications. It is estimated that at least 20 percent of individuals who undergo spinal fusion surgery experience the most common complication, which is that the surgery is not effective and fails to relieve neck or back pain. This, and similar long-term issues that may arise after spine surgery, is referred to as failed back surgery syndrome (FBSS).
FBSS can actually take many forms, ranging from increased pain after surgery to psychological manifestations like depression, insomnia and anxiety. In about five to 10 percent of patients, FBSS is caused by failure of the vertebrae to fully fuse after the surgery. This is a condition called pseudarthrosis.
Pseudarthrosis risk factors
There are a variety of reasons why vertebrae may not properly heal and fuse together following spinal fusion. Risk factors include:
- Smoking – The chemicals in nicotine decrease circulation and retard bone growth. Studies show that the rate of pseudarthrosis in smokers is nearly twice as high as in non-smokers.
- Pedicle screws – Small screws are implanted in adjacent vertebrae to hold them in place as the bones fuse, but these screws can break and prevent successful bone growth.
- Graft migration – A bone graft is placed between the adjacent vertebrae to facilitate the growth of new bone and fusion; the graft is usually placed in a small titanium cage, which can shift over time.
Pseudarthrosis can be one of the more painful spinal fusion complications because it causes symptoms similar to a bone fracture and can lead to nerve compression. A second surgery may be necessary to correct the problem.
Other possible spinal fusion complications
Other possible spinal fusion complications include nerve damage, scar tissue formation, pain above or below the level of fusion and bone graft rejection, among others. To learn more about these risks and find out about minimally invasive alternatives to spinal fusion, contact Laser Spine Institute for a complimentary review of your MRI or CT scan.