A procedure that "stuns" pain-sensing nerves might offer relief to people with severe arthritis of the hip or shoulder, a small, preliminary study suggests.
The procedure is a form of radiofrequency ablation, where doctors use needles to send a low-grade electrical current to nerves that are transmitting pain signals from the arthritic joint to the brain. The current heats and damages the nerve fibers, rendering them unable to deliver those pain messages.
In the United States, a number of ablation devices are cleared for treating low back pain and knee osteoarthritis.
At this point, the procedure is slowly becoming a more established treatment, said Dr. Felix Gonzalez, a radiologist at Emory University School of Medicine in Atlanta.
But whether ablation can help patients with severe hip or shoulder arthritis is unclear.
To find out, Gonzalez and his colleagues treated 23 patients whose hip or shoulder pain had become so bad that anti-inflammatory painkillers and cortisone injections -- two standard treatments -- were no longer helping.
Before undergoing ablation, and again three months later, patients answered standard questionnaires gauging their pain and daily function.
In the end, the study found, patients with shoulder arthritis reported an 85% drop in their pain ratings, on average. Among hip arthritis patients, pain declined by an average of 70%.
Gonzalez called the results "promising" and said, in his experience, there have been no major complications from the procedure, such as bleeding or infections -- though those are potential risks.
And before the ablation is done, Gonzalez explained, patients go through what is basically a trial run. They are given an injection of numbing medication near the nerves believed to be generating the pain signals. If the pain abates, that means targeting the same nerves with ablation will likely work, too -- longer term.
It's too soon, however, to judge the effectiveness of the approach for shoulder and hip pain, according to Dr. Rajat Bhatt, a rheumatologist who was not involved in the study.
None of the study patients received a placebo (inactive treatment) to serve as a comparison, said Bhatt, of Prime Rheumatology in Katy, Texas. So it's possible at least some of the pain relief came from the fact that patients received a novel therapy.
"With pain, there's generally a large placebo effect," Bhatt pointed out.
Larger studies, with a comparison group, are still needed, he said.
Gonzalez is scheduled to present the findings at the annual meeting of the Radiological Society of North America, being held online Nov. 29 to Dec. 5. Studies reported at meetings are generally considered preliminary until they are published in a peer-reviewed journal.
Osteoarthritis is exceedingly common, affecting more than 32.5 million Americans, according to the U.S. Centers for Disease Control and Prevention.
The condition arises when the cartilage cushioning the joint breaks down over time, leading to pain, stiffness and decreased range of motion.
People with osteoarthritis often take over-the-counter painkillers, such as ibuprofen (Advil, Motrin) and naproxen (Aleve). But besides being only moderately effective, the drugs are not without risks: Prolonged use is linked to increased risks of heart disease and kidney damage.
Corticosteroid injections, which reduce inflammation, are the next option. But their effectiveness wanes over time, Bhatt said, and there are long-term safety issues, including a risk of cartilage damage.
Beyond that, Gonzalez said, there are essentially two options for more severe pain: joint replacement surgery or opioid painkillers.
"But not everyone is a candidate for surgery, because of health reasons," Gonzalez said. "And some patients don't want it."
Opioids, meanwhile, carry their own well-documented problems, including the potential for addiction.
"So we need something to fill the gap," Gonzalez said.
Ablation stands as an additional therapy, he said, but it's not a "cure." For one, it addresses pain -- not the underlying joint damage of arthritis. And the pain is not banished forever: The nerve fibers eventually grow back.
When ablation is used for knee osteoarthritis, Gonzalez said, the pain relief typically lasts 6 months or more -- and up to two years in some patients. The procedure can be repeated.
In this early study, patients were only followed for three months. So it's not clear how long the pain relief will last, Gonzalez said.
And while ablation is coming into wider use for certain pain conditions, people may not be able to find it locally. Gonzalez said some of his patients come from hours away to get the treatment.
The Arthritis Foundation has more on osteoarthritis.
SOURCES: Felix Gonzalez, MD, assistant professor, department of radiology and imaging sciences, Emory University School of Medicine, Atlanta; Rajat Bhatt, MD, Prime Rheumatology, Katy, Texas; presentation, Radiological Society of North America virtual annual meeting, Nov. 29 to Dec. 5, 2020