Wearable lower limb haptic feedback device for retraining Foot Progression Angle and Step Width.

Area of Science:

• Biomedical Engineering
• Rehabilitation Technology
• Biomechanics

Background:

• Wearable devices with sensors and actuators are increasingly used for gait interventions to manage knee osteoarthritis progression.
• Wearable haptic feedback shows promise for modifying gait parameters to reduce knee adduction moments (KAM).
• Foot progression angle (FPA) and step width (SW) are key gait parameters influencing KAM.

Purpose of the Study:

• To assess if a custom haptic ankle bracelet can retrain healthy subjects to modify FPA and SW with 80% accuracy.
• To compare the number of steps needed for retraining between two feedback schemes (vibrotactile and tactile apparent movement).

Main Methods:

• Ten healthy subjects participated in a short training session using a custom haptic ankle bracelet.
• The device provided binary vibrotactile and tactile apparent movement feedback.
• Gait retraining focused on modifying foot progression angle (FPA) and step width (SW).

Main Results:

• Nine out of ten subjects successfully retrained their gait using the ankle bracelet in both feedback schemes.
• Participants achieved target FPA within 2° and SW within 39mm.
• No significant difference was found in the number of steps required between the two feedback schemes (p>0.05).

Conclusions:

• A single wearable haptic device can effectively retrain multiple gait parameters (FPA and SW) in healthy individuals.
• The findings support the potential of this haptic feedback system for future interventions in knee osteoarthritis patients.
• Further research is needed to evaluate device performance in patients and its effect on KAM.