Are glucocorticoid injections still necessary for osteoarthritis knee pain?

In patients with knee osteoarthritis, physical therapy may improve pain and functional disability more so than intraarticular glucocorticoid injections, at one year, according to a head-to-head study published in the New England Journal of Medicine.

The management of knee osteoarthritis, which is a leading cause of disability, is limited to the treatment of symptoms, commonly with glucocorticoid injections, until joint replacement in the late stages of disease. Practice guidelines vary regarding the use of glucocorticoid injections for knee osteoarthritis, and there are inconsistent reports regarding the extent and duration of symptom relief with this therapy. While complications with glucocorticoid injections are rare, they include joint infection, enhanced degradation of articular cartilage, and subchondral insufficiency fractures.

Physical therapy has shown short-term and long-term symptom relief, functional improvement, and pain reduction in knee osteoarthritis. However, the use of physical therapy for knee osteoarthritis declined between 2007 and 2015, and no practice guidelines recommend using these two treatments together.

While glucocorticoid injections are used more frequently than physical therapy, the difference between these two treatments in regard to pain relief and improved physical function is uncertain.

Gail Deyle, D.P.T, of Brooke Army Medical Center, in Fort Sam Houston, Texas, and colleagues undertook a randomized trial to compare physical therapy with glucocorticoid injections in 156 patients, mean age of 56 years, with osteoarthritis in one or both knees.

In the glucocorticoid injection group, the mean Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores were 108 at baseline and 55.8 at one year. The respective scores for the physical therapy group were 107 and 37.0. Physical therapy was also favored in the secondary outcomes that measured functional tasks and patient assessment of improvement.

Previous studies of physical therapy for knee osteoarthritis have shown large short-term benefits, but by one-year WOMAC scores have regressed toward baseline values.

“In our trial, we found a similar effect size for short-term improvement with physical therapy but an even greater reduction from baseline in the mean WOMAC score at one year,” the authors wrote. “This difference seen in our trial at one year may have been the result of the educational sessions, additional provider contact at four months and nine months, and the use of interim treatment visits as needed.”

REFERENCE

Gail D. Deyle, Chris S. Allen, Stephen C. Allison, et al. “Physical Therapy versus Glucocorticoid Injection for Osteoarthritis of the Knee.”New England Journal of Medicine. April 9, 2020. DOI: 10.1056/NEJMoa1905877