26. X-STOP ® Superior to Non-operative Care Differences between X-STOP and Control groups statistically significant (p < 0.001) at all follow-up intervals. (all 3 criteria) SOURCE: X-STOP ® IPD ® System Summary of Safety and Effectiveness (SSE); Includes all study sites.
27. Comparing X-STOP to Laminectomy SOURCE: Zucherman – Spine 2005 * Data from Zucherman – Spine 2005 cohort (n = 93) ** Data from Katz – Spine 1999 & Katz – Spinal Stenosis Data. Boston: Harvard Medical School, 2003:1-33 (n=197); These patients were worse at baseline than the X-STOP patients. (all 3 criteria)
Your spine consists of a column of 24 bones called vertebrae that extend from your skull down to your hips (Fig. 1). Between the vertebrae are discs of soft tissue. The spinous process are the bony structures that stick out of the vertebrae. Interspinous space is the area between the spinous process
The vertebrae are the building blocks, providing support for your head and body while the discs act as cushions, or “shock absorbers.” In addition to providing support, the spine encloses and protects a column of nerve tissues called the spinal cord. The spinal cord is surrounded by a bony channel called the spinal canal. In the lumbar spine, nerve roots pass out of the spinal canal through the intervertebral foramen, where they extend down into your back and legs. In the healthy spine, there is space between the spinal cord and the borders of the spinal canal so that the nerves are free and are not pinched. However, as we age the ligaments and bone that surround the spinal canal can thicken. This thickening results in narrowing of the spinal canal, which is called “spinal stenosis.” The spinal cord and nerve fibers that exit the spinal canal (nerve roots) become crowded and pinched due to this narrowing, resulting in pain and numbness in the back and legs.
Extension and Flexion are two “medical” terms that are challenging to remember but very important to understand if you suffer from lumbar spinal stenosis. For the purposes of this presentation, the easiest way to remember what each term means is to think of it this way: Extension happens when you stand and flexion happens when you sit or lean forward. This is important, because as you can see from the illustrations, the nerve area of the spine becomes more compact in extension and more open during flexion. Flexion occurs when you sit or bend forward. As you can see in the slide, bending forward opens up nerve area and may reduce symptoms.
When the patient stands straight up (extension), they extend their spines with the result being increased symptoms of stenosis. The best description that I’ve ever heard of these symptoms came from a patient who said to me “sometimes when I walk it feels like an electric storm shooting down my leg.” As the lumbar spine is in extension while standing, symptoms may be reduced by leaning forward and may be eliminated by sitting, which places the lumbar spine slightly into flexion.
Traditional LSS treatment options covered the extremes - ranging from non-operative care for mild symptoms to the invasive, open, tissue removing surgery such as laminectomy for more severe symptoms.
<Advance> X-STOP fills a need for a more moderate LSS treatment option X-STOP fills a gap in the continuum of care for patients who suffer from the symptoms of lumbar spinal stenosis that, until now, required patients to choose between conservative therapies, such as analgesics and injections, and traditional surgical decompression procedures, such as laminectomy
In the Pre-Op illustration we can see that the spinous processes (bony structures that stick out of the vertebra) are “kissing” and the nerve roots are compressed. The X-STOP implant is placed between the spinous processes separating then and relieving the pinched nerves of the symptomatic level during a minimally invasive surgical procedure
The X-STOP device relieves the symptoms of lumbar spinal stenosis by limiting extension without any significant restriction of flexion or lateral rotation. Additionally, the X-STOP Spacer addresses many of the traditional concerns about destabilization of the spine associated with invasive decompressive procedures such as laminectomy. The X-STOP procedure does not typically require removal of bony structures or the supraspinous ligament. Preserving the supraspinous ligament has the added benefit of working along with the device’s wings to prevent lateral and posterior migration.
The X-STOP Spacer was tested in a carefully controlled research study that took place in nine hospitals across the United States. In this study, 100 patients with lumbar spinal stenosis had surgery with the X-STOP Spacer. These patients were compared to 91 patients who did not have surgery, but were treated by their doctors with non-operative care (for example, with medications, physical therapy, etc.). In this study, the X-STOP Spacer was clinically proven to treat the major symptoms of lumbar spinal stenosis, by reducing pain and improving physical function, resulting in increased patient satisfaction, leading to overall treatment success.
How does X-STOP compare to decompressive laminectomy? To place the X-STOP outcomes in the spectrum of current treatments for LSS, you need to compare X-STOP outcomes to relevant literature regarding laminectomy outcomes. As reported in Zucherman – Spine 2005, this graph compares 2-year ZCQ outcomes for LSS patients treated with the X-STOP and decompressive laminectomy. X-STOP data is from Zucherman – Spine 2005 and includes all X-STOP patients, n = 93 Laminectomy data is from Katz – Spine 1999 and Katz – Spinal Stenosis Data. Harvard Medical School, 2003. Results from 197 patients. These patients were worse at baseline than the X-STOP patients.
Here we see the contraindications for the X-STOP implant.