Model-Driven Design of Electrical Stimulation Therapy Improves Gait Dynamics in Individuals With Limb Amputations

Area of Science:

• Biomedical Engineering
• Rehabilitation Science
• Musculoskeletal Modelling

Background:

• Amputation causes impaired gait, pain, and musculoskeletal deterioration, limiting mobility.
• Current functional electrical stimulation (FES) prescription relies on clinician experience, hindering optimal efficacy.
• Developing objective, model-driven FES strategies is crucial for effective gait rehabilitation.

Purpose of the Study:

• To design and evaluate an FES gait rehabilitation therapy for amputees using musculoskeletal modeling.
• To identify optimal stimulation targets and strategies for improving gait biomechanics.
• To validate the model-driven FES approach through in-silico and in-vivo assessments.

Main Methods:

• Integrated musculoskeletal modeling with optimal control simulations to identify FES strategies.
• Conducted an in-silico trial to determine target muscles for stimulation.
• Performed in-vivo gait analysis to evaluate FES-assisted walking performance.

Main Results:

• In-silico simulations identified vasti muscle stimulation as beneficial for modulating joint loading.
• In-vivo experiments confirmed reduced peak knee contact forces in the intact limb.
• Increased vasti muscle forces were observed in the amputated limb during FES-assisted walking.

Conclusions:

• Stimulating vasti muscles in the amputated limb enhances gait dynamics in transtibial amputees.
• This combined in-silico and in-vivo approach enables evidence-based digital tools for FES gait rehabilitation.
• The methodology holds potential for broader application in neurological and musculoskeletal gait impairments.