Posterior dynamic stabilization systems for use in spine surgery can be roughly divided into interspinous fixation devices and transpedicular fixation devices. Both categories include some devices that have been on the market (sometimes only in the EU) for some time, as well as new devices either still under development or under clinical testing in the US.
Interspinous fixation devices include the X-Stop (Kyphon, now owned by Medtronic), the Wallis (second generation), the DIAM Spinal Stabilization System (Medtronic Sofamor Danek), the coflex (from Paradigm Spine, not yet FDA approved), and the ExtenSure and CoRoent devices (NuVasive).
Interspinous process spacers fall under this category. These devices relieve stress and loading on the intervertebral disc and thus hopefully relieve pain. The spinous processes are the small prominences that are on the very back edge of the spinal column, just under the skin. Because the spinous processes are so close to the skin, interspinous process spacers may be inserted with `minimal cutting and dissection of tissues. The spacers are designed to distract (open up) the foramen, thus giving the nerves more room and relieving painful pinching of the nerves.
Developers of Interspinous Process Spacers
(note: see report #M510 for product status.)
Source: MedMarket Diligence, LLC; Report #M510, "Worldwide Spine Surgery."
These spacers may be inserted under only a mild sedative and local anesthesia, with the patient returning home the same day. The same-day surgery procedure makes this especially attractive to elderly patients, who may not be able to tolerate a longer, more extensive surgery performed under general anesthesia.