McPherson, who has performed the procedure 30 times during the last three years, praises it for its simplicity and effectiveness. It is used in the treatment of select cases of lumbar spinal stenosis, a narrowing of the boney spinal canal, which can cause crowding of the nerve roots and a variety of symptoms, including pain in the leg or lower back and numbness or tingling in the lower back and legs.
The procedure, which utilizes the X-Stop Spacer, a small titanium implant, can be an alternative to the more traditional laminectomy, a more complicated procedure that involves the removal of a small amount of bone. Both procedures work by enlarging the space between the bones in the back and reducing pressure on the spinal nerves.
“The X-Stop is essentially a smaller surgery than the laminectomy,” McPherson says. “It’s a 15- to 30-minute outpatient operation.”
The X-Stop, a device manufactured by Medtronic, is designed to accomplish what people with spinal stenosis often attempt to do for themselves.
“People with stenosis lean forward when they walk,” McPherson explains. “I can spot them in the grocery store because they’re leaning forward on their carts. When they flex forward, they open up the space in the spine for the nerves. People with stenosis are self-treating by flexing forward. The idea behind the X-Stop device is to recreate that flexion inside the body.”
The procedure is usually done under general anesthesia, although local anesthesia is an option. McPherson begins by making a small incision in the lower back. He then places the X-Stop between the spinous processes, the thin projections from the back of the spinal bones, in the affected area. The implant opens up space and prevents the patient from extending his or her back and putting pressure on the spinal nerves. Patients go home the same day.
McPherson says the procedure is suited to individuals with stenosis who experience pain relief when they lean forward and who are either unable to undergo a more involved surgical procedure or prefer to try a less invasive option.
Unlike the traditional laminectomy, which requires the cutting away of a small amount of bone, the X-Stop does not result in the destruction of any bone. “With a laminectomy, there is a small risk of creating instability, and fusion may be required to correct that instability,” McPherson says. “With the X-Stop, there is no risk of instability or the need for subsequent fusion.”
Published studies have shown that 70 to 80 percent of patients with lumbar stenosis who undergo the X-Stop procedure experience significant improvement of symptoms. If the procedure does not provide relief, a laminectomy remains an option.
The procedure, approved by the U.S. Food and Drug Administration in 2005, is covered by Medicare, and more than 10,000 of the procedures have been performed. Nevertheless, private insurers continue to regard it as experimental, which means that younger patients who wish to have the procedure must pay the expense out of pocket.
McPherson reports no conflicts with Medtronic.
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