Spine MRIs Often Show Harmless 'Defects': Study
After treatment, many people have visible evidence of a herniated disc without any symptoms
When sciatic pain doesn't go away, doctors often recommend imaging tests, such as MRIs, to rule out serious causes of the pain, such as a tumor, said Dr. Devon Klein, chief of musculoskeletal radiology at Lenox Hill Hospital in New York City.
The problem is that many people have herniated discs, often without any symptoms. Previous research has found that between 20 percent and 76 percent of people who don't have symptoms will show signs of disk herniation on an MRI, the study found.
Klein confirmed this. "If you take all comers and give them an MRI, you will see disc disease in most of them," he said. "Everyone hurts their back at some point."
Another issue is cost. MRIs can run from hundreds to thousands of dollars per scan, depending on where the test is conducted and whether the patient's insurance covers the expense.
The current study included nearly 300 people randomly assigned to receive either surgery or conservative care for their sciatic pain, all of whom had signs of disc herniation on their initial MRI. A follow-up MRI was done one year later, and the two MRIs were compared with patient results.
After a year, 84 percent of those in the study reported successful treatment. Follow-up MRIs showed that 35 percent of those with a favorable result still had disc herniation compared to 33 percent of those with an unfavorable result.
Favorable outcomes were reported in 85 percent of those with disc herniation on their follow-up MRI and in 83 percent of those without disc herniation, according to the study.
"I was shocked myself by the findings, as I do see a lot of patients with repeated MRI scanning, and I was a firm believer that a herniated disc with nerve root compression was causing the problems," said Peul.
"Now that we have proven that these recurrent or persistent sciatica and low-back complaints are less likely to be one-on-one related [to MRI findings], we should be more careful in our conclusions and promises about the outcomes of repeat surgery," Peul said.
Klein agreed. "Seeing a problem on an MRI doesn't necessarily ... confirm that that's where the pain is coming from," he said. "We see a fair percentage of patients with disc herniation who don't have symptoms. You can't treat the MRI. You have to treat the patient."