Evaluation of transradial body-powered prostheses using a robotic simulator

Area of Science:

• Biomedical Engineering
• Rehabilitation Technology
• Prosthetics

Background:

• Transradial body-powered prostheses are widely used by upper-limb amputees.
• Current prostheses can cause discomfort, fatigue, and skin issues due to high force and concentration demands.
• Optimizing prosthesis operation is crucial for improving amputee daily activity capacity.

Purpose of the Study:

• To identify optimal operational configurations for transradial body-powered prostheses.
• To minimize activation force while maximizing grip force for improved prosthesis function.

Main Methods:

• Development of a computer-controlled robotic amputee simulator.
• Systematic testing of various residual arm configurations (elbow, shoulder, scapular).
• Evaluation of prosthesis performance with a fitted transradial prosthesis.

Main Results:

• Increased shoulder flexion, scapular abduction, and elbow extension enhance gripper operation efficiency.
• Optimal placement of the ring harness near the C7 vertebra correlates with higher efficiency.
• Efficiency is defined as the ratio of grip force to cable tension.

Conclusions:

• Force transmission efficiency in body-powered prostheses is strongly linked to body posture.
• Findings can guide clinicians in fitting the ring harness (inferior to vertebra prominens) and instructing patients on posture.
• Optimized body posture and harness placement can minimize strain and maximize grip efficiency for amputees.