Surgeons in some areas are more likely to recommend surgery for low back problems and those differences in "surgeon enthusiasm" are a major factor driving regional variations in spinal surgery rates, suggests a study in the March 14 issue of Spine. The journal is published by Lippincott Williams & Wilkins, a part of Wolters Kluwer Health.

In contrast, variations in spinal surgery are unrelated to enthusiasm among patients and primary care doctors, according to the study, led by Dr. S. Samuel Bederman of University of California Irvine. The researchers write, "Strategies targeting surgeon practices may reduce regional variation in care and improve access disparities."

High Surgeon Enthusiasm Linked to Higher Surgery Rates

Using Ontario healthcare databases, Dr. Bederman and colleagues analyzed data on more than 50,000 surgeries performed for degenerative disease of the lumbar spine (lower back) from 2002 to 2006. In Ontario as in the United States, there are significant, unexplained "small-area variations" in the spinal surgery rate (although surgery rates in Ontario aren't as high as in the United States).

Differences in the back surgery rate between Ontario counties were compared with a previous survey in which surgeons, family physicians, and patients with back pain were asked about their preferences for spinal surgery. In that study, presented with different scenarios, surgeons were asked were asked whether they would recommend surgery, family doctors whether they would rate surgery appropriate, and patients whether they would consider surgery.

The results showed that surgeons were more likely to recommend surgery that is, had higher enthusiasm in counties with higher rates of spinal surgery. Comparing the top fourth with the bottom fourth of surgeon enthusiasm, there was a 20 percent difference in surgery rates.

In contrast, enthusiasm on the part of family physicians and patients with back pain were unrelated to variations in surgery rates. The variations were also unrelated to local differences in the rate of degenerative spine disease.

Surgeon Enthusiasm Is Key Modifiable Factor

Other factors affecting surgery rates included demographic factors like age, sex, and income, along with the presence of magnetic resonance imaging (MRI) scanners in the county. "Surgeon enthusiasm was found to be the dominant potentially modifiable factor influencing surgical rates," according to the authors.

Previous studies using Medicare data have found large variations in the rates of lumbar spine surgery across U.S. counties. These variations raise important concerns: If surgery rates are too high, then some patients are receiving unnecessary surgery and health care resources are being wasted. If surgery rates are too low, then some patients who could benefit from spinal surgery aren't receiving it.

Surgeon enthusiasm is one of the main factors driving regional variations in lumbar spine surgery, the new study suggests. Although they aren't the only factor driving the differences in surgery rates, surgeon preferences may be the factor most amenable to change.

Dr. Bederman and colleagues call for further research to understand why surgeons vary in their enthusiasm for surgery especially for conditions where there's strong scientific evidence for effectiveness, like "slipped" vertebrae caused by bone degeneration (spondylolisthesis) and narrowing (stenosis) of the spinal canal. They conclude, "With a better understanding of reasons for practice variation, we may be able to modify variation, reduce costs, and improve access to care."

Source: Lippincott Williams & Wilkins