Knee kinematics during walking at different speeds in people who have undergone total knee replacement

People who have undergone total knee replacement (TKR) experience difficulties in some daily activities including walking. Walking at faster speeds requires more knee flexion and may therefore present a greater challenge following TKR. The aim of this study was to compare the knee kinematics of patients following TKR and unimpaired controls during comfortable and fast walking speeds. Forty patients (22 women, 18 men) 12 months following TKR and 40 control participants (matched for age and sex) were assessed during walking at self-selected comfortable and fast speeds using three dimensional motion analysis. The group averages of spatiotemporal and peak kinematic characteristics in the sagittal, coronal and transverse movement planes were compared using univariate analysis of variance with walking speed as a co-variate. The TKR group walked with significantly reduced cadence (p < 0.001 at both speeds) and reduced stride length (p < 0.001 at both speeds), less knee flexion during stance and swing phases (p < 0.001 for both speeds) and less knee extension during stance phase (p < 0.024 for comfortable speed; p < 0.042 for fast speed). The TKR group also walked with less peak knee external rotation than controls at both speeds (p < 0.001 for both speeds). Both groups increased their velocity, cadence and stride length by a similar proportion when walking at fast speed. When walking at a faster speed, spatiotemporal gait parameters and knee motion are altered in a similar manner for both TKR patients and controls. However, at both walking speeds, TKR patients exhibit residual deficits 12 months following surgery.