Spinal surgery devices questioned
The use of implanted hardware in spinal fusion surgeries for lower back pain does not improve the results and carries a higher risk of complications, researchers reported today.
The study published in the journal Spine was the latest to cast doubt on the increasingly common use of spinal screws and cages during surgeries in which vertebrae are fused to relieve pain.
The findings “should add to our level of skepticism about benefits of the hardware and the procedure itself,” said Dr. Richard A. Deyo, a professor of medicine at the University of Washington who was not involved in the study. Deyo has researched back pain treatments and his lab is partly supported with funds from a device maker.
More than 150,000 Americans undergo spinal fusions for lower back pain each year. The process involves using bone grafts with or without surgical implants to fuse two or more vertebrae.
The surgery is performed when the vertebrae or the cushioning disks between vertebrae become weakened or damaged by injury or disease. The procedure became popular with the introduction in 1996 of spinal cages, devices that hold bone grafts in place while keeping pressure off the disk.
Among Medicare recipients, spinal fusion surgeries quadrupled to a rate of 12 per 10,000 in 2003 from 3 per 10,000 in 1992, according to a report last month from researchers at Dartmouth Medical School.
Recent European studies have raised questions about the benefits of spinal fusion in general.
A head-to-head study in Britain last year found spinal surgery offered no clear advantages over intensive rehabilitation therapy for patients with chronic lower back pain. This year, a Norwegian study found spinal fusion was no better than physical therapy in patients who had undergone previous back surgery. Both studies involved the use of implants.
In the latest report, researchers from the University of Washington examined records from that state’s workers compensation system on 1,950 workers who had spinal fusion surgery for chronic lower back pain from 1994 to 2001.
Patients fell into four groups. Some received only cages; others received other devices, such as rods and screws; another group received cages plus other devices; the final group did not get implants.
Two years after surgery, about 60% of patients in each group remained disabled, researchers said. Patients with implants, however, had twice the risk of post-surgical complications.
Dr. Gary M. Franklin, medical director of the Washington Department of Labor and Industry, which funded the study, said it was clear that the devices did not benefit patients.
But he added that the high rate of long-term disability in all of the patients suggested that spinal fusion, regardless of whether hardware was used or not, was of little benefit.
“My view is that the data is pretty incontrovertible at this point. This procedure doesn’t do much to help people,” said Franklin, an author of the study.
Dr. James Wang, a spinal surgeon at UCLA, cautioned against applying the findings to the general population.
Wang said that workers’ compensation patients generally seem to do worse in studies than other patients.
Wang, a consultant to three companies that market spinal surgery devices, added that it looked as though many patients in the study were not candidates for spinal fusion surgery in the first place.
About 30% of patients in the study had a pinched nerve, and fusion surgery is “not appropriate” in such cases unless something else is wrong, Wang said.
*
