Mobile-bearing insert used with total knee arthroplasty does not rotate on the tibial tray during a squatting activity: a cross-sectional study

Table 3 Rotation excursions during squatting activity

	10 weeks postoperatively	1 year postoperatively	p values
Knee extension angle (degrees)	− 2.0 [− 5.5, 1.6]	− 3.2 [− 10.9, 4.4]	0.709
Knee flexion angle (degrees)	55.3 [44.6, 66.0]	57.1 [46.7, 67.6]	0.760
FEM/TIB (degrees)	5.7 [4.2, 7.3]	6.3 [4.3, 7.8]	0.702
FEM/INS (degrees)	5.9 [4.5, 7.2] ※	5.5 [3.8, 7.2] †	0.547
INS/TIB (degrees)	1.8 [1.4, 2.2] ※	1.6 [1.1, 2.2] †	0.517
p value (FEM/INS with INS/TIB)	< 0.001	< 0.001

Mean [95% CI]
※FEM/INS was significantly greater than that of INS/TIB at 10 weeks postoperatively
† FEM/INS was significantly greater than that of INS/TIB at 1 year postoperatively
FEM/TIB rotation of the femoral component relative to the tibial component, FEM/INS rotation of the femoral component relative to the polyethylene insert, INS/TIB: rotation of the polyethylene insert relative to the tibial component, p value probability value, 95% CI 95% confidence interval

ISSN: 1749-799X