Americans are spending more money than ever to treat spine problems, but their backs are not getting any better.

Those are the findings of a report in The Journal of the American Medical Association, which found that spending on spine treatments in the United States totaled nearly $86 billion in 2005, a rise of 65 percent from 1997, after adjusting for inflation. Even so, the proportion of people with impaired function because of spine problems increased during the period, even after controlling for an aging population.

“You’d think if you’re putting a lot of money into a problem, you’d see some improvements in health status,” said Brook I. Martin, research scientist at the Department of Orthopedics and Sports Medicine at the University of Washington and lead author on the study, published Wednesday. “We’re putting a lot of money into this problem, and it’s a big investment in health care expenditures, but we’re not seeing health status commensurate with those investments.”

The report is the latest to suggest that the nation is losing its battle against back pain, and that many popular treatments may be ineffective or overused. Researchers have produced conflicting data about the effectiveness of spinal surgery for back pain, although one major clinical trial, known by the acronym Sport, showed that spinal surgery patients did better than patients receiving more conservative care, which included medications or physical therapy. However, some doctors have questioned whether surgeries, injections and narcotic pain medications are being used appropriately.