The Effects of Different Walking Inclinations on Knee Angle in the Frontal Plane of Patients with Varus Malalignment

Purpose: Given the high prevalence of varus malalignment of the knee and the consequences of walking on different surfaces on this malalignment, the aim of the present study was to investigate the effect of walking inclination on knee angle in the frontal plane of patients with varus malalignment. Methods: 18 male subjects with varus malalignment classified at grade 3 bowleg, within the age range of 19-24 years, volunteered to participate in this study. The parameters of knee angle in the frontal plane at the moments of heel contact, midstance and toe off when walking on -7.5, zero, +5 and +10 percent of treadmill inclination were calculated using three-dimensional motion analysis system with six optoelectronic cameras. Repeated measures of variance and non-parametric Friedman test were used for data analysis. Results: The results of the present study showed that as walking inclination increases, knee angle in the frontal plane decreases. The only significant differences were related to varus angle between +10 and zero percent inclinations at the moment of midstance (P<0.001) and between -7.5 and zero percent inclinations at the moment of toe off (P<0.001) and in case of other parameters, no significant differences were observed. Conclusion: According to the obtained results, walking on upslope surfaces, probably is a suitable solution to reduce the load exerted on the knee and prevent premature osteoarthritis in young individuals with varus malalignment.