Once Shull and his colleagues established that the technology could help healthy people learn new walking patterns, they decided to test it on people with symptomatic knee osteoarthritis.

In a 2013 study published in the Journal of Orthopaedic Research, the researchers had 10 people with medial compartment knee OA and self-reported pain participate in weekly gait retraining sessions for six weeks. The participants’ walking motions, knee loading, pain and function were evaluated prior to beginning the weekly sessions and one month after completing them. 

Using the WOMAC index for the post-training evaluation, participants’ scores for pain and function improved by 29 percent and 32 percent respectively – changes approximately 75 percent larger than the expected placebo effect, the researchers reported. WOMAC, the Western Ontario and McMaster Universities Osteoarthritis Index, is a questionnaire widely used by health professionals to evaluate the condition of patients with OA of the hip and knee.

Shull wants to know if these improvements can be sustained. “We are now working on long-term studies to determine the effect of this treatment several years after implementation,” he says.

Researchers at University of British Columbia and University of Melbourne have also been studying how changes in gait may lessen knee burden. In a 2012 study published in Arthritis Care and Research, researchers asked 22 participants with knee OA to shift the lean of their trunks sideways toward their damaged knee, guiding them to stick to the new walk through biofeedback

“The amount of trunk lean was measured and displayed in front of the participant as he walked toward a screen,” says study author Michael Hunt, PT, PhD, assistant professor in the Department of Physical Therapy, University of British Columbia in Vancouver. “A target area onscreen guided the amount of lean.”

Although the greater the lean, the less pressure on the inner joint, participants had a tough time learning the new walk and initially at least, found no pain reduction.

Similarly, a 2013 study by the same group, which examined the effects of altering foot progression angles in 22 patients with knee OA, showed no immediate change in knee pain or other symptoms.  

“We need three months or more to look at the effect on pain,” says Hunt. “And we also need to see what is going on in other joints. Are we taking the burden off the knee and putting it somewhere else?”

Nor is it clear how much lean is enough, says Hunt. And too much lean, even if terrific for the joint, may not be best for balance.