Interspinous implants to treat spinal stenosis

Lumbar spinal stenosis has historically been treated with open decompressive surgery which is associated with significant morbidity and may give rise to various complications. Interspinous spacers (ISS) have been developed as a less invasive strategy which may serve to avoid many of these risks. The two current spacers that are FDA approved and commercially available are the Coflex and Superion devices. The goal is to review these two implants, their indications, and patient selection.

The Coflex device has been shown to be analogous to decompression and fusion when treating moderate spinal stenosis. It provides dynamic stability after a decompression is performed, without the rigidity of pedicle-screw instrumentation. Recent results show improved outcomes in Coflex patients at 3 years of follow-up, as compared to decompression and fusion. The Superion implant is placed percutaneously in the interspinous space with minimal disruption of spinal anatomy. When compared to the X-Stop device (which is no longer available), the Superion implant shows improved outcomes at 3 years of follow-up. ISS are lesser invasive options as compared to formal decompression and fusion for the treatment of lumbar spinal stenosis.