Mechanically and physiologically optimizing prosthetic elevated vacuum systems in people with transtibial amputation:...

Area of Science:

• Biomedical Engineering
• Prosthetics and Orthotics
• Rehabilitation Science

Background:

• Elevated vacuum (EV) suspension is crucial for prosthetic socket fit and function.
• Optimal EV pressure is user-specific, influenced by factors like suspension needs, socket fit, components, and health.

Purpose of the Study:

• To evaluate the mechanical and physiological effects of EV pressure.
• To determine optimal EV pressure settings for individual prosthesis users.

Main Methods:

• Instrumented EV sockets were used with embedded sensors to measure limb movement.
• Limb fluid volume and user-reported comfort were recorded at various EV pressure settings during an activity protocol.

Main Results:

• Increased EV pressure reduced limb-socket displacement, with significant reduction (81-93%) at a setting of 12 (~ -9 inHg).
• Limb-socket displacement varied by sensor location, indicating individual differences in socket fit or residual limb characteristics.
• Changes in limb fluid volume and socket comfort did not consistently correlate with EV pressure, suggesting a complex, individual-specific relationship.

Conclusions:

• Individual responses to EV pressure settings are key for optimization.
• Balancing mechanical and physiological effects of EV can improve clinical outcomes in prosthetic users.