Effects of orthotic insole on gait patterns in children with mild leg length discrepancy

Leg length discrepancy (LLD) is commonly associated with compensatory gait strategies leading to musculoskeletal disorders of the lower extremity and lumbar spine. Orthotic insole (OI) is considered as a conservative treatment for patients with mild LLD, especially for children. However, the restoration of normal gait when wearing OI with foot lift are still poorly understood. What are the immediate effects of OI on the gait patterns in children with mild LLD? Gait data and plantar pressure data were collected for 12 children with mild anatomical LLD in barefoot and OI conditions. Paired t-test was performed to determine the changes in gait between these two conditions, and also the symmetry between limbs in the same condition for spatiotemporal, kinematic, and kinetic variables. Children with mild LLD showed an immediate gait improvement confirmed by increased step length and velocity, decreased peak plantar pressure in both limbs with OI. Additionally, the significant between-limb differences disappeared for peak ankle dorsiflexion, hip adduction, pelvis upward obliquity and also second peak plantar pressure with OI, which improved gait symmetry. This study provides a better understanding of the immediate effect of OI with foot lift on biomechanical changes in gait, which identify that OI with foot lift could be a potential therapeutic option for children with mild structural LLD to improve gait metrics. •Children with mild LLD increased step length and velocity in both limbs with OI.•The peak plantar pressure decreased with OI compared with barefoot walking.•The differences of peak ankle dorsiflexion between limbs disappeared with OI.•The gait symmetry between limbs improved with OI for children with mild LLD.•OI with foot lift may be a potential therapeutic option for children with mild LLD.