Backache sufferers who fear pain change movements

Aug 7 2007

People who fear aggravating a backache will change the way they move to prevent more pain, a new study finds.

But doing so may set the stage for further injury, researchers warn.

In a study published in the journal Spine, Ohio University researchers Jim Thomas and Christopher France examined 36 adults who recently had experienced lower back pain. They split them into two groups: one that confessed a high fear of aggravating the backache and another that was less afraid of reinjury.

The researchers next asked the participants to perform a series of three reaching tasks designed to simulate everyday activities, such as bending to open a mailbox or leaning to ring a doorbell. Sensors attached to the study subjects recorded their muscle movements.

The study confirmed what researchers have long suspected: People with a high fear of back pain will twist, bend and make other unusual moves to try to avoid more aches. It might be okay to baby sore muscles for a while, but protecting them for too long can cause them to weaken. When those muscles are called into play unexpectedly -- such as lurching forward to grab a bag of falling groceries -- more injury can occur, said Thomas, an associate professor of physical therapy whose study is funded by a four-year, $1.5 million grant from the National Institutes of Health.

"It's like if you run every day, and then a friend invites you to a game of racquetball," Thomas said, noting that the sports use different muscle groups. "The next day you suddenly feel like you've been run over by a bus."

The latest findings are part of a larger study that also is tracking 100 subjects in Athens and Columbus, Ohio, for a year after their recovery from a back pain injury. This second piece, which will wrap up in May 2008, aims to confirm whether pain avoiders are indeed more likely to reinjure their backs. About half of the data has been collected to date, in partnership with Ohio State University, Thomas said.

Researchers hope the study findings will help physicians create new treatments for backaches, a common ailment. Eight out of 10 adults will suffer from back pain at some point in their lives. While many of those aches go away on their own, about half of those people will experience a recurrence of pain within the following year. Medical expenses and work absenteeism due to back pain disability are estimated at $20 billion to $40 billion per year in the United States, according to the researchers.