Optimization of Active Backpack Loading Patterns to Improve the Walking Performance for Individuals With a Unilateral...

Area of Science:

• Biomechanics
• Rehabilitation Engineering
• Human Movement Science

Background:

• Individuals with unilateral transtibial amputation (TTA) exhibit gait asymmetry, worsened by load carriage.
• Passive prostheses cannot adapt stiffness, increasing strain on the intact limb and metabolic cost.
• Previous research on load-suspended backpacks focused on healthy populations.

Purpose of the Study:

• To investigate active backpack loading strategies for individuals with TTA.
• To optimize metabolic cost, forward propulsion, and intact knee joint loading.
• To assess the efficacy of active backpacks in improving walking performance.

Main Methods:

• A musculoskeletal simulation-based optimization framework was employed.
• Time-varying actuator forces were simulated for active backpacks during the gait cycle.
• Actuation patterns were optimized for specific biomechanical criteria.

Main Results:

• All simulated active backpack patterns improved walking performance compared to passive systems.
• Reduced force impulse from dynamic load was observed across all active backpack conditions.
• Increased forward propulsion, decreased intact knee loading, and improved metabolic cost were noted.

Conclusions:

• Active backpacks show significant potential to enhance walking performance for individuals with TTA during load carriage.
• The benefits were consistent across different optimization criteria, suggesting a robust effect.
• Active backpacks offer a promising assistive technology for improving mobility and reducing injury risk.