Tailored exercise program improves function and reduces pain due to knee osteoarthritis

Reference

Torstensen TA, Østerås H, LoMartire R, Rugelbak GM, Grooten WJA, Äng BO. High- versus low-dose exercise therapy for knee osteoarthritis: a randomized controlled multicenter trial. Ann Intern Med 2023;176(2):154-165.

Synopsis

For this study, conducted in Norway and Sweden, the researchers enrolled 189 patients between the ages of 45 and 85 years with knee osteoarthritis and a history of pain and decreased knee function. The patients did not have previous therapy. Using concealed allocation, the authors assigned participants to either 20 to 30 minutes of low-dose exercise therapy (2 sets of 10 repetitions) or 70 to 90 minutes of high-dose exercise therapy (3 sets of 30 repetitions), tailored to their specific needs by a physical therapist. Both groups were given instruction on how to perform the exercises and how to adjust the weight to perform without pain. The participants were asked to perform the exercises, on their own, 3 times a week for 12 weeks. Both groups improved over time to a similar extent for most outcomes of pain and function using the Knee Injury and Osteoarthritis Outcome Score, with approximately half the participants experiencing a clinically meaningful improvement in all outcome categories. High-dose exercise was associated with approximately 20% more participants achieving a clinically important improvement on the Function in Sport and Recreation score, which lasted for 3 months after the end of the study. A few quibbles: The study may have been underpowered to find the minimally clinically important difference between treatments, if one existed. As one might expect, 23% of participants dropped out of the study over the 3 months. Given a possible placebo response in this unmasked study, I would have suggested the authors include a "usual care" group as the third comparator.