The device described here has not been used for several years, but I have a page on this device here since it was used more commonly at one point. I might occasionally see a patient who has had one of these devices inserted. As I don't do this procedure, this page is for informational purposes only.
The device was known as an X-Stop, from a company called Kyphon, and it involved putting a spacer between the spinous processes to create more room for the nerve roots. The idea behind this device was to separate the space between the spinal bones, to counteract the loss of space from the degeneration and loss of disc height.
With the X-stop spreader, the space between the spinous processes can be increased, making more room for the nerves.
This procedure can often be done through a small incision.
To see an animation about this procedure, click here.
Though it can be done with a small incision, I don't believe the decompression is as much as can be done by directly removing some of the compressing overgrown soft tissue (ligament), and can also be associated with later collapse of the space between the bones. Additionally, it causes a forward bend at the treated site which means the other sites have to compensate by bending back more, and can result in narrowing of the adjacent levels. However, the device has some use in patients who could not tolerate a longer surgery and anesthetic.