Changes in medial-to-lateral knee joint loading patterns assessed by Dual-Energy X-ray Absorptiometry following supervised neuromuscular exercise therapy and patient education in patients with knee osteoarthritis: an exploratory cohort study

Background: The mechanisms underlying pain reductions following exercise therapy in patients with knee osteoarthritis (OA) are poorly understood. One mechanism could be changes in mechanical knee joint loading.

Objective: To investigate if a neuromuscular exercise therapy and patient education intervention could alter knee joint loading assessed by Dual-Energy X-ray Absorptiometry (DXA) in people with knee OA.

Methods: Participants with symptomatic knee OA were evaluated before and 26 weeks after an 8-week supervised neuromuscular exercise therapy and patient education intervention (Good Life with OsteoArthritis in Denmark). DXA scans were used to estimate the medial-to-lateral tibial plateau bone mineral density (BMD) ratio. The Knee Injury and Osteoarthritis Outcome Score was used to assess improvements in knee pain, symptoms, physical function, and knee-related quality of life. Changes in physical function were assessed with the 30-second chair stand test and the 40-meter fast paced walk test.

Results: Of 42 participants recruited, 30 (21 females, mean age 64 � 7.9 years) had full data available. Medial-to-lateral tibial BMD ratio increased non-significantly by 0.02 (95% CI −0.01 to 0.06) (indicating higher medial load) from baseline to 26-weeks follow-up. Participants had statistically significant improvements of 21% in pain, 17% in symptoms, 14% in ADL, 17% in knee-related quality of life, 13% in chair stand ability, and 6% in walking speed.

Conclusions: In this exploratory cohort study, following an 8-weeks supervised exercise therapy and patient education intervention, the medial-to-lateral tibial BMD ratio did not seem to change.