The mean changes ( improvements ) in the primary outcome measures were as follows : Lysholm score , 21.7 points in the partial-meniscectomy group as compared with 23.3 points in the sham-surgery group ( between-group difference , -1.6 points ; 95 % confidence interval [ CI ] , -7.2 to 4.0 ) ; WOMET score , 24.6 and 27.1 points , respectively ( between-group difference , -2.5 points ; 95 % CI , -9.2 to 4.1 ) ; and score for knee pain after exercise , 3.1 and 3.3 points , respectively ( between-group difference , -0.1 ; 95 % CI , -0.9 to 0.7 ) .