X STOP Device Gives Relief From Painful Neurogenic Claudication
Neurogenic intermittent claudication (NIC) is a condition that causes pain in the low back and legs when standing. The symptoms go away or get better when sitting or bending forward. Neurogenic refers to the nerves and spinal cord. Intermittent means it comes and goes. Claudication is the sensation of pain or discomfort that comes with this condition.

In this study, a small device called the X STOP was placed between two spinous processess of the spine. The procedure is called an interspinous process decompression (IPD). This oval spacer is designed to increase the width and diameter of the spinal canal. The spinal canal is the opening in the vertebral bone that allows the spinal cord to pass from the skull down to the bottom of the spine.

Two groups of patients were compared. Patients in both groups had NIC caused by a condition called degenerative spondylolisthesis. In spondylolisthesis, one vertebra moves forward over the vertebra below it. This movement has the effect of closing down the spinal canal. It also puts traction on the spinal cord or spinal nerves.

The first group of patients had an IPD with the X STOP inserted surgically. The second (control) group was treated conservatively without an operation. Conservative care included steroid injection, nonsteroidal antiinflammatory drugs (NSAIDs), pain relievers, and physical therapy as needed.

Results based on symptoms, function, and patient satisfaction was measured over two years. The authors report a 63 percent improvement in the IPD group compared to only 13 percent in the control group. The authors conclude the X STOP is safe and effective in the treatment of NIC caused by spondylolisthesis. Further study is needed to find out which patients are the best candidates for the X STOP.
Paul A. Anderson, MD, et al. Treatment of Neurogenic Claudication By Interspinous Decompression: Application of the X STOP Device in Patients with Lumbar Degenerative Spondylolisthesis. In Journal of Neurosurgery: Spine. June 2006. Vol. 4. No. 6. Pp. 464-471.