Preliminary study of a robotic foot-ankle prosthesis with active alignment

Area of Science:

• Biomedical Engineering
• Biomechanics
• Prosthetics and Orthotics

Background:

• Traditional robotic prosthetic foot-ankle prostheses utilize revolute joints to mimic natural joint biomechanics.
• Existing designs may not fully optimize power injection or reduce residual limb loading during the gait cycle.

Purpose of the Study:

• To evaluate a novel robotic ankle prosthesis incorporating active alignment.
• To assess the impact of this active alignment on gait biomechanics and residual limb loading.

Main Methods:

• A single-subject biomechanics analysis was conducted.
• The robotic ankle prosthesis with a four-bar mechanism for active alignment was tested.
• Kinematics of the ankle joint and pylon segment were altered to reduce residual limb loading.

Main Results:

• A 10% reduction in peak residual limb pressures was observed with active alignment.
• Evidence of greater gait symmetry in ground reaction forces was found.
• Active alignment demonstrated potential for improved gait characteristics.

Conclusions:

• The robotic ankle prosthesis with active alignment shows promise for enhancing amputee mobility.
• This design may offer advantages over conventional revolute joint prostheses.
• Further research is warranted to validate these preliminary findings in a larger cohort.