Vibrotactile Feedback Improves Foot Placement Perception on Stairs for Lower-Limb Prosthesis Users

Area of Science:

• Biomedical Engineering
• Rehabilitation Technology
• Neuroscience

Background:

• Lower-limb amputees face significant challenges in stair ambulation, with many unable to use stairs independently.
• Lack of tactile sensation in the residual limb leads to uncertainty in foot placement, impacting mobility and quality of life.

Purpose of the Study:

• To design and evaluate a haptic feedback system that provides vibrotactile cues for foot placement during stair negotiation.
• To assess the efficacy of this sensory feedback system in improving stair descent performance for lower-limb amputees.

Main Methods:

• Development of a thigh-worn vibrotactile feedback system delivering cues about foot position relative to stair steps.
• Evaluation through tactor discrimination tests and foot placement awareness tests in control participants and below-knee amputees.

Main Results:

• Control participants (N=10) and below-knee amputees (N=2) demonstrated high accuracy (95.4% and 90.1%) in discriminating individual tactor vibrations.
• Vibrotactile feedback significantly increased accuracy in reporting foot placement by 15% (controls) and 17.5% (amputees).

Conclusions:

• Vibrotactile sensory feedback holds promise for enhancing stair ambulation in lower-limb amputees.
• Integrating haptic feedback into prosthetics may help overcome sensory deficits and improve functional mobility.