Effect of shoe insole on the dynamics of lower extremities in individuals with leg length discrepancy during walking

Abstract

Introduction: The aim of the present study was to investigate the effect of Internal and External Heel Lift Insoles (IHLI, EHLI) on pelvic kinematics and lower extremity joint moments in subject with mild leg length discrepancy (LLD) during the Stance Phase of walking.

Methods: From twenty-eight men with mild LLD, kinematic and kinetic data were collected while they walked under each of three conditions (IHLI, EHLI and shoe). Data were collected for both limbs using a six-camera system synchronized with a force platform. For comparisons the dependent variables among the conditions, repeated measures ANCOVA and Bonferroni's post hoc test were used (P ≤ 0.05).

Results: For both IHLI and EHLI, there were significant decreases in peak long leg lateral and anterior pelvic tilt, long leg hip and knee abduction moments, and short leg ankle plantar flexor moment (P ≤ 0.001). Furthermore, significant increases in peak lateral and anterior pelvic tilt of the short leg were observed in the IHLI and EHLI conditions as compared to the shoe (SH) condition (p ≤ 0.01). In addition, a significant difference was observed between the IHLI and EHLI conditions in the peak values of anterior pelvic tilt of the long leg (p = 0.043) and ankle plantar flexor moment of the short leg (p = 0.044).

Conclusion: Findings suggest that the use of IHLI and EHLI may be effective in improving pelvic movements (lateral and anterior tilt) and gait dynamics in individuals with LLD. The EHLI could reduce more the peak plantar flexor moment of the short leg and peak anterior pelvic tilt of the long leg than IHLI during stance phase of walking.

Keywords: Kinematics; Leg length discrepancy; Moment; Shoe insole; Walking.