“…The description and standardization of knee flexion measurements have been neglected in many experiments, and only a few studies have provided detailed methodology [1][2][3][4]6,13,19,21,[24][25][26][27][28][29][30][31][32][33][34] . A review of the literature revealed that three types in position have been used in measurements of knee flexion of patients with TKA, including supine [1][2][3]6,13,[24][25][26][27] , prone 28) , and sitting 19,29,30) , although some studies/ r e p o r t s g a v e n o i n f o r m a t i o n a b o u t t h e position 4,21,[31][32][33][34] .…”