Associations amongst dynamic knee stiffness during gait, quadriceps stiffness, and the incidence of knee osteoarthritis over 24 months: a cohort study with a mediation analysis oleh Zongpan Li, Kam-Lun Leung, Chen Huang, Xiuping Huang, Shan Su, Raymond CK Chung, Changhai Ding, Siu-Ngor Fu