By Mukund I. Gundanna, MD
My doctor says I need a fusion. What does that mean?
There are many different kinds of surgeries for the spine. Typically when our nerves – which travel down the center of the spine – get pressure on them, the nerves get irritated and cause pain that radiates down the arm or leg, to the area where the nerves go. This is called “radiculopathy.”
The main question is: Why are your nerves getting pressurized? That answer determines what surgeries should be done.
The back rim of a disc in the spine can buckle or rupture, or the spinal joints can overgrow from arthritis. Therapy, medications, and spinal anti-inflammatory injections don’t relieve enough pain. Your surgeon will then get two imaging studies: an MRI, and x-rays, ideally with you standing. If the spinal column has a good alignment, you may not need a fusion at all, and might do well with a decompression where your surgeon removes the offending portions of disc and joints.
In other situations, which show up on weight-bearing x-rays, your spine might be collapsing to the side (scoliosis) or one vertebra might be shifted forward (spondylolisthesis). This is like an earthquake that cuts and shifts the road lanes.
In these cases, if “pressure” is removed from your nerves, your spine might become even more unstable, and your problem might worsen. You need more than a decompression – you need a fusion. This means that your surgeon will surgically move your bones back into proper alignment. Next, the bones have to be permanently held in that correct position. Your surgeon will use a combination of metal and plastic implants to lock those bones together so they cannot re-shift. This is called “fusion.”
Not all fusions are equal
There are so many ways to fuse. Though the technical details are complicated, techniques can be split into two general categories: open and Minimally Invasive Surgery. Both try to accomplish the same thing: restore spinal alignment and nerve canal integrity, and solidly hold it together so that the repair can heal.
The difference is in open surgery, incisions are large and a lot of the muscle is detached and retracted to access the spine. When the work is done, the muscle is reattached, if possible. This healing can be long and painful, and the muscles do not recover fully.
In MIS, attention is directed to minimizing retraction and injury by choosing less invasive techniques that conform to natural anatomy. There still is some injury, but the MIS surgeon will try to keep this to a minimum. The MIS surgeon will try to keep bone intact to allow muscles to maintain their attachments.
If you need a fusion, it is important to remember that your recovery is extremely dependent on the amount of muscle injury. MIS is not a type of surgery, but a philosophy to keep the patient’s anatomy as intact while still getting the work done. As technology improves, surgical techniques also improve. When considering spine surgery, it is important to discuss the options for MIS techniques with your surgeon.
Mukund I. Gundanna, MD, is the founder of Brazos Spine and is a Board Certified surgeon with advanced Fellowship training in spine surgery.