issue Summer 2023

The Injection Question

By Dawn Rhodes
Dr. Darbandi studying images in a lab at RFU. His team's findings have appeared on popular health news sites, including Medscape and WebMD.
Photo by Michael R. Schmidt

Corticosteroids or Hyaluronic Acid for Knee Osteoarthritis?

Research teams from both RFU and the University of California, San Francisco are shedding light on two popular noninvasive treatments for knee osteoarthritis, uncovering results that suggest hyaluronic acid injections should be further explored, while the common approach of corticosteroid injections should be used more cautiously.

For the millions who struggle with constant knee pain because of osteoarthritis, doctors might consider a corticosteroid injection to provide temporary relief. But recent studies, including one authored by Azad Darbandi, MD ’23, show that common treatment may actually worsen your joints long-term.

RFU researchers used radiographic images to analyze the progression of osteoarthritis in 150 people. Pulling data from the Osteoarthritis Initiative sponsored by the National Institutes of Health, Dr. Darbandi and fellow researchers split patients into three groups: people who received no injections for treatment, patients who got corticosteroid shots and patients who got hyaluronic acid injections over a three-year period.

Researchers also matched the patients based on other conditions shown to contribute to osteoarthritis, like smoking, diabetes and rheumatoid arthritis. According to Dr. Darbandi, they excluded patients who previously had surgery, or who had received corticosteroid and hyaluronic acid injections.

X-rays were examined for factors like medial joint space, a common indicator of arthritis, and the researchers found that osteoarthritis worsened faster in patients who received corticosteroid injections, Dr. Darbandi said.

Researchers at the University of California, San Francisco, did similar research that revealed similar conclusions. Both studies were presented in November at the Radiological Society of North America.

Dr. Darbandi said the results weren’t surprising, because there are limits to the use of corticosteroid injections.

“The main surprise was the hyaluronic acid data and the comparison with corticosteroids,” he said. “I was surprised that the hyaluronic acid injections had better outcomes than the corticosteroid injections, which suggests more research needs to be done into that type of injection.”

Dr. Darbandi said he previously found research showing that corticosteroids could contribute to poor postoperative outcomes, like in rotator cuff surgery. He added that he wanted to use radiology and clinical findings to explore impacts of the drug on osteoarthritis treatment before surgery.

There’s long been evidence that such injections aren’t always the best option, Dr. Darbandi said. He added that physicians usually recommend weight loss, exercise, physical therapy and nonsteroidal anti-inflammatory drugs before considering corticosteroids, which can reduce inflammation and relieve pain for one to three months.

But according to Dr. Darbandi, there isn’t much research scrutinizing the long-term effects of steroids on joint health.

Does this new research mean doctors should eschew corticosteroids? Not necessarily.

It’s not fair to say corticosteroids have no benefit, Dr. Darbandi said. For some patients, he added, physicians may decide that short-term pain relief is needed to help a patient jump-start exercise and physical therapy.

“You have to look at the demographic of a patient receiving these injections,” Dr. Darbandi said. “Sometimes they’re a little older. Are they more concerned about the disease progression of their osteoarthritis or pain management? If they’re younger, their joints have more life to live, so a more conservative approach may be preferred.”

“I was surprised that the hyaluronic acid injections had better outcomes than the corticosteroid injections, which suggests more research needs to be done into that type of injection.”

He added that it’s also important to note that findings on a patient’s X-rays don’t always match up to clinical exams and the pain a patient is having.

“You might take an X-ray of someone’s knee and it looks fine, but they’re having severe pain,” Dr. Darbandi said. “Or you might take an image of someone’s knee and it looks bad, but they’re not experiencing much pain.”

It does mean providers and patients need to be more wary of when and how to use corticosteroids, and what the risks are, Dr. Darbandi added.

The results also don’t necessarily mean hyaluronic acid is a viable swap for corticosteroids, said Dr. Darbandi, adding that for one thing, there is insufficient research into hyaluronic acid injections. That type of injection typically is not covered by insurance like corticosteroids are, greatly limiting which patients could consider it as a treatment option.

For hyaluronic acid or other alternatives, the effects remain controversial, Dr. Darbandi said. For his research, it wasn’t necessarily feasible to control for a patient’s socioeconomic status. Dr. Darbandi also questions if there is a placebo effect from when a patient pays out of pocket for a less common form of treatment, versus something broadly covered by insurance.

“So if more studies are done looking at hyaluronic acid injections in a more objective lens, maybe over the course of time, it can be used as a form of standard of care,” Dr. Darbandi said.

Dawn Rhodes is a Chicago-based writer and editor. She’s worked in journalism for more than a decade.