Role of physical activity in cartilage damage progression of subjects with baseline full-thickness cartilage defects in medial tibiofemoral compartment: data from the Osteoarthritis Initiative

Abstract

To assess the association between physical activity and cartilage damage progression in medial tibiofemoral compartment (MTFC) using 2-year follow-up magnetic resonance imaging (MRI) in subjects with denuded areas of subchondral bone (dABs) at the central weight-bearing medial femur (cMF) at baseline MRI examination. One hundred subjects from the Osteoarthritis Initiative (OAI) progression cohort with dABs at the cMF at 3T MRI at baseline (51% men; mean age 62.2 years, range 45-79) were included. Sagittal 3D dual-echo steady-state with water excitation images were used to assess 2-year MTFC cartilage change. Associations between 2-year average Physical Activity Scale for the Elderly (PASE) and 2-year MTFC cartilage change were assessed by linear regression analysis. Subgroup analyses were performed. No associations between PASE and 2-year MTFC cartilage change were observed in the entire cohort. Similarly, in the subgroup with cartilage loss during the 2 years, the non-refuted confidence intervals for the regression coefficients were tightly clustered around the null value (regression coefficients for: mean cMF.ThCtAB=-0.00059; 98.75% CI:-0.00130 to 0.00012), cMF.dAB%=0.02176; 98.75% CI:-0.02514 to 0.06865, Mean MT.ThCtAB=-0.00013; 98.75% CI:-0.00064 to 0.00038, MT.dAB%=0.02543; 98.75% CI:-0.01485 to 0.06571. In the entire group of subjects with dABs at the cMF at baseline, no association between physical activity and 2-year MTFC cartilage change was detected. Due to the limited sample size of our study, small-sized effects may not have been detected in our study.