Exercise alone insufficient to protect knees from osteoarthritis

Exercise alone was not enough to prevent cartilage degeneration among patients who were obese or overweight and trying to lose weight, according to findings recently presented at the Radiological Society of North America Annual Meeting.

“Once cartilage is lost in osteoarthritis, the disease cannot be reversed,” Alexandra Gersing, MD, a postdoctoral scholar in the department of radiology and biomedical imaging at the University of California, San Francisco, said in a press release.

Participants from the Osteoarthritis Initiative with a BMI greater than 25 kg/m² who were at risk for radiographic mild-to-moderate osteoarthritis and who lost more than 5% of their baseline BMI (n = 380) were matched in a 1:1 ratio to controls with stable weight. They were grouped based on their weight loss method (exercise only, diet only, diet and exercise). MRIs were performed on the right knee at baseline, 48 and 96 months. T2 relaxation time changes of cartilage composition was assessed.

Gersing and colleagues found that after 96 months, weight loss through exercise alone showed no significant difference in change of T2 vs. controls with stable weight (P = .56), but morphological knee abnormalities were significantly lower in the weight loss group overall vs. controls (P < .001). Patients with weight loss showed a significantly less T2value increase in the bone layer of all sections (P < .03 for each) vs. controls with stable weight. In addition, rates of increase in cartilage T2 averaged over all sections were lowest in the diet (P = .042) and diet and exercise (P = .003) groups.

“These results add to the hypothesis that solely exercise as a regimen in order to lose weight in overweight and obese adults may not be as beneficial to the knee joint as weight loss regimens involving diet," Gersing said in the release. - by Janel Miller

Reference: Gersing A, et al. Abstract SSJ16-03. Presented at: Radiological Society of North America Annual Meeting. Nov. 26–Dec. 1, 2017; Chicago.

Disclosures: Healio Family Medicine was unable to determine the authors’relevant financial disclosures prior to publication.