Electromyographically controlled prosthetic wrist improves dexterity and reduces compensatory movements without added...

Area of Science:

• Biomedical Engineering
• Rehabilitation Science
• Prosthetics and Orthotics

Background:

• Restoring wrist function is crucial for transradial amputees' daily activities.
• The impact of powered prosthetic wrists on function, biomechanics, and cognition remains incompletely understood.

Purpose of the Study:

• To quantify the effects of myoelectric prosthetic wrists on task performance, compensatory movements, and cognitive load in transradial amputees.
• To evaluate a new, inexpensive "Utah wrist" for research and a commercial powered wrist.

Main Methods:

• Three transradial amputees performed a modified Clothespin Relocation Task with myoelectric prostheses, both with and without powered wrists.
• Task failure rates, compensatory body movements (forward leaning, leftward bending), and cognitive load (NASA-TLX, secondary task) were measured.

Main Results:

• Task failure decreased significantly with the Utah wrist (66% to 39%) and the commercial wrist.
• Compensatory forward leaning and leftward bending movements were significantly reduced with both prosthetic wrists.
• No significant increase in cognitive load was observed with either powered prosthetic wrist.

Conclusions:

• Functional prosthetic wrists enhance dexterity and reduce compensatory movements in transradial amputees.
• Powered prosthetic wrists can be integrated without substantially increasing cognitive demand.
• Findings support the development and prescription of prosthetic wrists to improve upper-limb prosthesis outcomes.