Effect of Leg Length Discrepancy on Dynamic Gait Stability

Area of Science:

• Biomechanics
• Gait Analysis
• Human Movement Science

Background:

• Leg length discrepancy (LLD) is common and may affect gait dynamics.
• The impact of LLD on dynamic gait stability and compensatory strategies remains unclear.

Purpose of the Study:

• To investigate the effect of LLD on dynamic gait stability.
• To identify compensatory kinematic and dynamic strategies used to maintain stability with LLD.

Main Methods:

• Nineteen healthy males walked with and without a 3 cm LLD.
• Kinematic and kinetic data were collected using 3D motion analysis and force plates.
• Extrapolated center of mass and margin of stability were calculated.

Main Results:

• Lateral stability was maintained in both LLD and no-LLD conditions.
• The short leg side showed frontal plane joint and muscle activity changes.
• The long leg side exhibited a significant negative correlation between trunk lateral flexion and margin of stability.

Conclusions:

• The body employs complex strategies to maintain gait stability despite LLD.
• Short leg compensation involves joint and muscle adjustments.
• Long leg compensation involves active trunk lateral flexion adjustments.