The proposed prospective, multi-center, randomized, open label, active control, parallel assignment clinical trial is currently recruiting approximately 400 participants. The study endpoint is the rate of overall subject success at 24 months.

The Superion is a interspinous spacer titanium metal implant that is delivered through a small 12-15 millimeter incision in the patient’s back. The implant is placed percutaneously between the spinous processes without the need to cut paraspinal muscles. The interspinous spacer is designed to distract (open) the foramen, where the nerve endings pass away from the center of the spinal region and into the legs. These devices may also unload the intervertebral disc and they may limit spinal extension (the position the spine takes on when bending backward).

The study official title is A Prospective, Multi-Center, Randomized Study Comparing the VertiFlex Superion Interspinous Spacer (ISS) to the X-STOP Interspinous Process Decompression (IPD) System in Patients With Moderate Lumbar Spinal Stenosis.