It's the no. 2 reason Americans visit the doctor and the No. 3 cause of surgeries. Back pain is almost as common as, well, the common cold.
Until now, patients with debilitating back pain might have been diagnosed with a torn disc and advised to have corrective surgery. But a new Stanford study suggests that the problem may be as much mental as it is physical.
Researchers found that torn discs are common even in people who have no trouble twisting, turning and bending. But these people don't experience symptoms. The difference? Patients with severe, ongoing pain were much more likely to be struggling with emotional problems. "Basically, what we showed is that the amount of discomfort that people have . . . is, in many patients, most closely related to psychological and social issues," says Eugene Carragee, MD '82, an associate professor of functional restoration and lead author of the study.
Tears in the discs can appear as high-intensity zones on an MRI scan. In a process called discography, doctors confirm the presence of a tear by injecting the disc with dye. Until now, physicians have thought that the identification of a high-intensity zone coupled with discomfort from dye leaking out after the injection meant that the damaged disc was the source of the patient's back problems.
But when Carragee compared the MRI and discography results of 96 patients, he found that people whose discs had high-intensity zones were only slightly more likely to experience back pain during normal activity than those without obvious disc problems. And high-intensity zones showed up in 25 percent of people who had no symptoms of low back pain. This suggests that not every disc tear is painful, and not all low back pain results from a damaged disc.
A better predictor of pain, he found, is an abnormal result on a psychological screening given to all study participants before the back examinations. He theorizes that emotional factors may influence people's perceptions of pain. Carragee's prescription? Reassurance and gentle exercise, which can improve both the back pain and the patient's sense of well-being. It's a cheap and simple treatment if it works -- and in any case, it can't hurt.
