Surgeons now have another option for treating patients with lumbar spinal stenosis. Before the recently approved X-Stop Interspinous Process Decompression (IPD®), the surgical treatment for lumbar spinal stenosis was a lumbar laminectomy, during which bone and ligamentous material are removed from the spinal canal to reduce narrowing. The X-Stop IPD is a titanium implant placed between the spinous processes of the symptomatic discs during a minimally invasive surgical procedure that can usually be performed on an outpatient basis.
Robert Ward, MD, with the Cullman Spine Institute, began performing the X-Stop procedure a little over a year ago, after studying the clinical trial results. "Essentially 90% of the patients were obtaining excellent pain relief," Ward said. "The gold standard operation for spinal stenosis is a lumbar laminectomy to decompress the spinal canal. This device (X-Stop) actually prevents many of the patients from having a lumbar laminectomy, which requires a bigger operation, with a longer, more painful recovery versus the X-Stop, which is minimally invasive."
Thomas Wilson, MD, with Neurosurgical Associates, did his first X-Stop implant a few months ago and finds it effective. "The traditional surgery involves essentially removing some of the bone and ligamentous elements at the back of the spine," Wilson said. "Sometimes that bony removal results in instability, in which case the vertebrae become progressively out of line, which necessitates going in and revising it with a big procedure called a fusion. The X-Stop avoids the removal of any of those structural elements, thereby alleviating these potential problems."
Both Ward and Wilson agree that trying the X-Stop before performing a lumbar laminectomy is the most conservative option for most patients. "You haven't burned any bridges," Wilson said. "If it doesn't work, you can always resort to the more traditional forms of surgical treatment. The two individuals that I've placed these devices in have had a condition that rendered them more susceptible to post-op instability. The vertebrae were already slightly out of line. It's an ideal opportunity to treat those patients without subjecting them to the increased risk of post-op instability."
"The X-Stop is much less invasive," Ward said. "And if it doesn't work, which is rare, then you can remove the device through the same incision and do the laminectomy."
Although the procedure is appropriate for most patients, there are some individuals who are not good candidates. "I've had several patients whose spinal canal was entirely too tight to do the X-Stop procedure," Ward said. "I didn't think I could give them enough relief with this procedure."
Patients who would not be candidates for this procedure are those in which there is demonstrable instability preoperatively and those with multilevel stenosis, or narrowing in more than just one area. If either of these conditions exists, a lumbar laminectomy would be needed.
Thus far, Wilson has done two patients with good results. "I talked to my first X-Stop patient, a retired physician, yesterday and he was thrilled," Wilson said. "He couldn't even walk before the operation. He wasn't able to play golf, and now he's playing four times a week.
Over the past year, Ward has done nearly 40 X-Stop procedures. "I've only had one patient who has begun to experience leg pain to the point that I may have to take her back and perform a laminectomy, which, if this procedure fails, would be the definitive treatment."
"I generally treat patients conservatively as long as I can with medication, physical therapy, home exercises, and epidural steroid injections," Ward said. "None of these treatments will actually alleviate the spinal stenosis. They will alleviate some of the symptoms. I have some patients who receive epidural steroids that go many months, sometimes years, before they eventually have to have surgery. Those patients who fail this sort of treatment are then candidates for the X-Stop or laminectomy."
Depending on the severity of the stenosis, if X-Stop or laminectomy is not performed, the patient may "continue to experience severe leg pain that will become worse with time to the point that they are unable to ambulate," Ward said. "I have seen a few patients who couldn't have surgery or refused to have surgery who had to use a wheelchair for ambulation."
The signs that would indicate that a patient may be a candidate for this procedure are pain in the back, buttocks, and sometimes the legs when the patient is standing or walking.
"I would encourage physicians to look more at the clinical history," Ward said. "The physical exam is often normal in patients with spinal stenosis, as far as reflexes, sensation, and strength in their extremities, but their pain is particularly bad with standing or walking. Put more emphasis on the clinical history of the patient versus the imaging studies." Dr. Ward said that often x-rays and even MRIs may appear normal or show only mild narrowing when the patients are actually experiencing severe pain.
"It's an excellent alternative to a lumbar laminectomy," Ward said. "It's minimally invasive with less postoperative pain, less blood loss, less perioperative problems—including the risk of infection—and quicker recovery. If the procedure does not fail (which is less than 10%), patients can return to normal. Spinal surgery is definitely headed toward minimally invasive techniques."
