Is it Justified Based on Available Medical Evidence, Dartmouth Researchers Ask Rates of lumbar fusion in the United States have increased more than 250 percent over the past decade, according to a study appearing in the Nov. 1 edition of the journal, Spine. Yet, study authors from Dartmouth Medical School (DMS) and Dartmouth-Hitchcock Medical Centre (DHMC) raise concerns that without scientific or clinical evidence to prove such procedures are effective for most low back conditions, there is no way of knowing if the increase is warranted. And, with variations in rates of the surgery as much as 20 times greater in some regions of the US than in others, they call on the medical, academic, corporate and governmental communities to come together to support the necessary research into these conditions that affect millions of people each day.
The cost increase in spinal fusion has been more than 500 percent among Medicare patients alone, rising from $75 million in 1992 to $482 million in 2003. While other common procedures such as laminectomy and disectomy have actually decreased slightly in recent years, rates of lumbar fusion rose from 0.3 per 1,000 Medicare enrollees in 1992 to 1.1 per 1,000 in 2003. Lumbar or spinal fusion is a procedure designed to stabilize the spine by fusing bones together and theoretically providing protection and relief of back pain for degenerative joints in the back. "What's most disquieting about these findings is that we really haven't advanced our knowledge as to whether fusion, for several back conditions, works for our patients," said lead author Dr. James N. Weinstein. "Lumbar fusion now accounts from almost 50 percent of all back surgery performed in the US. Clearly, we are doing more and more of it, but we have not provided the scientific or clinical evidence to support these procedures." Weinstein, a surgeon who is professor and chair of orthopaedics at DMS and DHMC and a member of the Centre for the Evaluative Clinical Sciences at DMS. He and his co-authors point to the lack of randomized clinical trials as the reason for the uncertainty about the procedure's efficacy and effectiveness. "Left alone, practice variations will not go away. Expansion of the research agenda will require not only the early evaluation of new technologies and new theories about the use of current technologies, but also the ongoing evaluation of existing practice," they write. Addressing this problem will require the work of academic medical centres, physicians, and national funding and regulatory agencies, such as the NIH, CMS and FDA, they argue. In addition to variation between rates in the US and the rest of the world, the study shows "striking" variation in regions within the US. For example, in 2002, lumbar fusion was performed on 4.6 out of 1,000 Medicare patients in Idaho Falls, ID, while in cities such as Bangor, ME, Covington, KY, and Terre Haute, IN, an average of 1.0 patients per 1,000 underwent the procedure. Other regions with unusually high rates of the surgery included Missoula, MT, Mason City, IA, Bradenton, FL, and Casper, WY. Reasons for the geographic variations internationally and nationally are not fully understood, but the authors suggest that "lack of scientific evidence, financial incentives and disincentives to surgical intervention, and difference in clinical training and professional opinion" are underlying causes. (Source: Spine : Dartmouth-Hitchcock Medical Centre: November 2006.)