Knee Arthritis Made Worse by Steroid Injections
/By Pat Anson
Corticosteroid injections are often given to patients with osteoarthritis to reduce pain and inflammation in the knee joint, with the relief sometimes lasting for days, weeks or even months. A new study, however, found that steroid injections in the knee may only make arthritis worse in the long run.
The study by researchers at the University of California, San Francisco (UCSF) compared the long-term effects of corticosteroid injections to patients who received injections of hyaluronic acid, a polymer gel that acts as a lubricant and shock absorber.
The research, recently published in the journal Radiology, found that a single hyaluronic acid injection was associated with decreased progression of knee osteoarthritis up to two years later. Just one corticosteroid injection led to more knee joint damage.
“Our study directly challenges a common clinical practice: the use of corticosteroid injections for knee osteoarthritis symptom relief,” said lead author Upasana Bharadwaj, MD, who was a research fellow in the Department of Radiology at UCSF at the time of the research. “It presents robust evidence that corticosteroids accelerate structural knee degeneration, even after a single injection.”
Osteoarthritis (OA) is the most common form of arthritis, with the knee being the most frequently affected joint. Over 32 million U.S. adults have knee OA, and about 10% of them receive corticosteroid or hyaluronic injections.
UCSF researchers followed 70 patients with knee OA who had one injection -- 44 were injected with corticosteroids and 26 were given hyaluronic acid. MRI images were taken before, at the time of, and two years after the injection to assess how much damage and OA progression occurred in the knee joint over time. The scores were then compared to a control group of 140 patients who did not receive any injection.
The researcher team found that both types of injections helped reduce knee pain, but the corticosteroid injections were associated with more joint damage than both the control group and those who received hyaluronic acid injections. In contrast, the hyaluronic acid injections appeared to slow the progression of joint damage.
“The most striking finding is that a single corticosteroid injection led to significantly greater structural damage in the knee joint over two years, especially in cartilage, while hyaluronic acid injections not only avoided this damage but actually showed reduced joint deterioration post-injection,” Bharadwaj said. “Corticosteroids are known to reduce inflammation but also impair the repair mechanisms of cartilage.
“This study could lead to more judicious use of corticosteroid injections, especially for patients with mild to moderate osteoarthritis who are not yet surgical candidates.”
Current guidelines for knee OA often recommend corticosteroid injections for short-term pain relief, but limit the injections to one every three months or no more than three injections per year. Bharadwaj hopes the new research will persuade clinicians to opt for hyaluronic acid injections more frequently and stop the routine use of corticosteroids for knee OA.
“Given their widespread use, these findings could influence clinical guidelines and patient care decisions, encouraging more cautious use and stronger consideration of alternatives like hyaluronic acid,” she said. “The public impact is significant, as osteoarthritis is a major global cause of disability, and millions receive such injections annually.”
A 2022 study by researchers at the Chicago Medical School also compared corticosteroid injections for knee OA to hyaluronic acid injections. That study used X-ray images to evaluate patients after two years and came to the same conclusion that corticosteroids worsened osteoarthritis progression.
