(RxWiki News) They're no magic bullet, but injections might trump some pills for knee arthritis pain relief.
A new study found that injection treatments — whether they contained corticosteroids, hyaluronic acid or a placebo — better relieved pain from knee osteoarthritis than the most common treatment, acetaminophen (brand name Tylenol).
Raveendhara Bannuru, MD, of the Tufts Medical Center in Boston, led this study.
Lisa A. Mandl, MD, MPH, of Weill Cornell Medical School in New York City, and Elena Losina, PhD, of Harvard Medical School in Boston, wrote in an editorial about the current study that the work of Dr. Bannuru and team helps ensure that patients are getting the best pain relief for knee osteoarthritis.
Drs. Mandl and Losina wrote that "it will become increasingly important to create innovative research models to better understand how to optimize pain control and provide a road map for a rational approach to effective treatment."
Knee osteoarthritis is a common form of arthritis in which the knee bone cartilage wears down over time.
Dr. Bannuru and team looked at 137 past studies on knee osteoarthritis treatments that compared two or more treatments at a time. These studies were published between 1980 and 2014 and involved a total of 33,243 patients.
These researchers looked at several treatments for knee osteoarthritis, such as diclofenac (Voltaren), ibuprofen (Advil), naproxen (Aleve), celecoxib (Celebrex), corticosteroid injections (a shot of steroids to lessen inflammation), hyaluronic acid injections (a shot of natural fluid found in the body), an oral placebo (fake treatment) and placebo injections. Patients reported their level of pain with each treatment.
Dr. Bannuru and team found that acetaminophen did not offer significant pain relief over the long run. They found that corticosteroid injections and hyaluronic injections each offered better pain relief than acetaminophen.
All the injection treatments — even placebo injections — worked better than oral treatments, Dr. Bannuru and colleagues found. This may be due to the placebo effect, these researchers noted.
In the placebo effect, a patient may think that a certain treatment works better than the other when that may not necessarily be true. In this case, patients getting a shot might have thought that it worked faster than taking pills since it went directly to the bloodstream.
“One striking aspect of our results is that [injection] therapies were the most effective treatments for knee osteoarthritis pain,” Dr. Bannuru and team wrote. “This result is especially [true of] hyaluronic acid, which is a treatment generally considered by expert panels to be minimally effective.”
Dr. Bannuru and colleagues concluded that “This information, along with the safety profiles and relative costs of included treatments, will be helpful for individualized patient care decisions."
This study was published Jan. 5 in the Annals of Internal Medicine.
The Agency for Healthcare Research and Quality (AHRQ) funded this study. Dr. Bannuru received grants from the AHRQ. Dr. John B. Wong received grants from the Patient-Centered Outcomes Research Institute and the National Institutes of Health National Center for Complementary and Alternative Medicine. Dr. Timothy E. McAlindon received grants from Croma, Flexion Therapeutics, the National Institutes of Health, the AHRQ and Bioventus.