Steroid injections worsen knee arthritis, studies find

Two recent studies found that corticosteroid knee injections were strongly linked to the overall progression of osteoarthritis in the knee.

The results of both studies were presented at the annual meeting of the Radiological Society of North America on Tuesday. Both studies focused on osteoarthritis, a chronic, degenerative, progressive condition that’s considered to be the most common form of arthritis, according to researchers.

More than 10 percent of those with osteoarthrosis in the knee use corticosteroid or hyaluronic acid injections to decrease pain, according to researchers. While the corticosteroids provide temporary relief, long-term effects of the steroids are not fully understood. For both studies, scientists compared the effects of hyaluronic injections, corticosteroid injections, and no injections on osteoarthritic progression in the knee.

The first study was conducted by researchers at the University of California, San Francisco. It included 210 patients from the Osteoarthritis Initiative. Of the participants, 70 received intraarticular injections, 44 were injected with corticosteroids and 26 were injected with hyaluronic acid. The remaining 140 participants served as the control group and received no injections.

The trial period lasted two years. Before and after the trial, magnetic resonance imaging (MRI) was performed on all patients. Researchers assessed the MRI scans with whole-organ magnetic resonance imaging score (WORMS), which graded the knee osteopathic by observing the meniscus, bone marrow lesions, cartilage, joint effusion, and ligaments. Researchers measured progression based on the differences between the patients’ WORMS before and after the trial.

Corticosteroid knee injections were significantly associated the overall progression of osteoarthritis in the knee. Areas of the knee with the greatest progression included the lateral meniscus, lateral cartilage, and medial cartilage.

 “While both corticosteroid and hyaluronic acid injections are reported to help with symptomatic pain relief for knee osteoarthritis, our results conclusively show that corticosteroids are associated with significant progression of knee osteoarthritis up to two years post-injection and must be administered with caution,” Upadhyay Bharadwaj, MD, of UC, San Francisco said in a statement. “Hyaluronic acid, on the other hand, may slow down progression of knee osteoarthritis and alleviate long-term effects while offering symptomatic relief.”

The second study was conducted by researchers from Chicago Medical School of Rosalind Franklin University of Medicine and Science. For this investigation, researchers used X-ray imaging on the knee to observe how hyaluronic acid injections and corticosteroid injections impacted the progression of osteoarthritis.

The study’s cohort included 150 patients, 50 of them received corticosteroid injections, another 50 received hyaluronic acid injections, and the final 50 received no injections. The trial period lasted for 36 months.

After comparing X-ray results from before and after the trial period, researchers found that corticosteroid injections were associated with worse imaging hallmarks of osteoarthritis. Hyaluronic acid, however, did not appear to worsen the progression of osteoarthritis in the knee.

According to the study’s authors, these findings suggest that corticosteroids may have harmful long-term effects on the progression of osteoarthritis in the knee, and hyaluronic acid may be a safer option that should be further researched.