Selection of subjects. *pairwise matching by age, BMI, KL grade, subcohort and clinical site. Overall 200 subjects in 100 matched pairs were included in the analysis. Due to dropouts the data set contained 38 matched pairs with a complete MRIs at all time points. At month 72, the data of 45 individuals was available in each group including 38 complete pairs and seven individuals each, who lost their matching partner.