"You can miss a very high percentage," Cohen suggested.

Both procedures have similar complication rates, Cohen said, which are caused by inserting the needle into the spine.


"The chance of serious complications is incredibly low, much, much less than 1 percent," he said. The most common side effect of the RF ablation therapy is temporary, increased pain from inflamed nerves, which can occur in 10 percent of patients, Cohen said.

In the study, the researchers looked at 151 patients, largely from the military, at Johns Hopkins, Walter Reed and other affiliated sites.

The patients were randomly separated into three groups of about 50 people each. One group got radiofrequency ablation based on clinical findings, another got the treatment after only one diagnostic block, and the last after two blocks -- the standard of care.

The researchers found that of all the patients in each group, one-third in the first group had relief lasting at least three months, compared with 16 percent in the second and 22 percent in the third group. Drilling down, though, the researchers found those in the group getting two nerve blocks before treatment had one of the best treatment success rates. Of the 14 patients who ultimately got the radiofrequency procedure in that group, nine successfully had their pain relieved, Cohen pointed out.

"So it's very successful for those people," Cohen said. "They really probably had arthritis causing their pain."

But overall, going straight to the RF ablation was the most cost-effective, according to the researchers' models.

The team calculated the cost of successful treatment by taking the total cost of all procedures, a missed work day, and a decrease in monthly medication expenses due to pain relief. According to the model, the costs of going straight for radiofrequency therapy without nerve blocks was $6,286; for only one block before the therapy, $17,142; and for two blocks before RF, $15,241.

Inspired by the military

Cohen got involved in the study after his experience in the military, he said. Soldiers in Iraq or Afghanistan needing treatment have to be flown into camp by helicopter, which is always risky, and generally have less than a week to get mended before being sent back to duty, hardly enough time for the many days it takes for two nerve blocks and then the radiofrequency ablation treatment.

"You're transporting people around in Blackhawk helicopters," Cohen said. "These things crash; it's expensive and dangerous."

Still, Cohen notes that nerve blocks will remain necessary for some patients, especially ones who are candidates for surgery.

More Industry Headlines