December 28, 2008
The Wall Street Journal
Spinal Surgery to Get You on Your Feet Faster
A new minimally invasive spinal surgery trims hospital stays and affords a shorter recovery time than traditional methods, says a company that sells equipment used in the procedure. Physicians say the surgery trims recovery times but say more research is needed on its efficacy. * * * When degenerated discs in the spine cause chronic back pain, surgeons sometimes do a procedure called lumbar fusion, in which two or more vertebrae of the spine are fused to each other. The procedure, which typically involves screws, rods and a bone graft, is designed to cut down on unwanted abnormal motion and realign the spine. Lumbar fusion does a good job of relieving pain for some patients, but not for others, for reasons that aren't fully understood. A major downside is a long recovery period. Patients typically stay in the hospital two to five days, and it can take six to 12 weeks before they can return to sedentary work. The new surgery, called AxiaLIF, cuts the hospital stay down to one night or less in most cases, according to TranS1 Inc., a Wilmington, N.C., company that sells equipment used in the surgery. The surgery has been approved by the Food and Drug Administration since 2005 to fuse the lowest two vertebrae of the spine, and was approved earlier this year to treat the third-lowest vertebra, known as L4. While traditional surgery involves cutting through muscle tissue in the abdomen or back to get to the spine, the AxiaLIF procedure involves a one-inch incision near the tailbone. The cut goes into the "presacral space," a cavity in the pelvis that is generally empty except for fat. A titanium rod is used to attach two vertebrae, and bone-grafting material is added. Often screws are added for stability. Since muscle isn't cut -- except sometimes small cuts to put in screws -- says Cincinnati surgeon William Tobler, patients have less pain and a faster recovery. They are often able to return to sedentary work in two or three weeks, though he recommends they take it easy for a month. Dr. Tobler, a consultant to TranS1, says he owns a small stock position in the company. In results presented in a poster at the Congress of Neurological Surgeons meeting in October in Orlando, Fla., Dr. Tobler found that among 50 patients, pain and disability on standard rating scales was reduced by about 50% one year after the surgery. Of the total, 88% had achieved "fusion" -- a successful result in which added bone bridges two vertebrae. Dr. Tobler says the results are comparable to standard surgery, but so far there have been no large head-to-head trials. Many surgeons question whether AxiaLIF is really as effective as traditional spinal surgery. Alexander R. Vacarro, professor of orthopedic surgery and neurosurgery at Thomas Jefferson University's Rothman Institute in Philadelphia, says more efficacy data from independent surgeons not connected with the company is needed. Complications of the AxiaLIF surgery are few, but can include damage to the bowel. Out of the 5,400 AxiaLIF surgeries done world-wide since 2003, 30 patients have had injury during the procedure to the bowel, which can be anything from a small pinch to a tear causing a serious infection, the company says. While the complication is rare, it can be extremely unpleasant, involving a "diverting colostomy," in which waste is diverted to an externally worn bag for a month or two while the bowel recovers.