No single physical therapy treatment improved all of the outcomes researchers were looking at – disability, pain and function – at the same time.

However, this is not the final word on nondrug interventions for knee OA. In their paper, the researchers acknowledge several key shortcomings of the evidence they analyzed: Study quality varied, many of the therapies are not used alone, some didn’t consider or document whether people were taking medications for OA, and some didn’t take weight loss into account.

What’s more, the American College of Rheumatology (ACR) this year released updated recommendations for the management of hip and knee OA. For knee OA specifically, tai chi, acupuncture and TENS (transcutaneous electrical nerve stimulation) were conditionally recommended.

Despite the study’s limitations, experts say the results are useful.

“Studies that use a large amount of literature to determine which treatments are beneficial are very important,” says Julie Keysor, PhD, director of the Center for Enhancing Activity and Participation Among Persons with Arthritis, and an associate professor of physical therapy at Boston University. “There are numerous therapies – exercise, modalities and education – for arthritis, and it’s critical that doctors and consumers know what works and what doesn’t.”

In the case of this review, the strongest conclusions were in line with established guidelines from ACR and the Osteoarthritis Research Society International, which state that interventions empowering people to actively self-manage knee OA (such as aerobic, aquatic and strength exercise) can improve outcomes.

“If people with knee OA don’t exercise or engage in strength-training activities, they should talk with their doctor about getting started,” Keysor says. “Many doctors won’t bring it up, so it’s important that people initiate the conversation. In addition, people should consider seeing a physical therapist if they are having difficulty engaging in an exercise program.”