ABSTRACT

EVOLUTION OF TECHNIQUE Since the late 1990s ISP process implants have been used for patients with mild to moderate intermittent neurogenic claudication. The X-Stop spacer (Medtronic Sofamor Danek, Minneapolis, MN) was approved for this use at one or two levels by the FDA in November 2006. A less invasive device called the Superion Interspinous Spacer System (VertiFlex, San Clemente, CA) is under clinical investigation in the United States and is being compared with the X-Stop device in the trial. A number of other companies have developed similar devices that produce local distraction of the spinous processes and lamina, similar to the X-Stop spacer.