Design of semi-open prosthetic socket with constant force for lower limb.

Area of Science:

• Biomedical Engineering
• Materials Science

Background:

• Prosthetic socket fit is crucial for residual limb adaptation.
• Residual limb volume fluctuations cause interface pressure mismatch, leading to skin and fit issues.
• Addressing volume fluctuation is essential for successful prosthetic socket application.

Purpose of the Study:

• To design a prosthetic socket with a constant force unit to mitigate residual limb volume fluctuation issues.
• To improve the adaptation and comfort of residual limb to prosthetic sockets.

Main Methods:

• A constant force unit was designed utilizing the superelasticity of shape memory alloy.
• A semi-open prosthetic socket was developed, incorporating the constant force unit.
• Finite element analysis was employed to optimize and verify the prosthetic socket's constant force properties.

Main Results:

• The constant force unit demonstrated a maximum constant force region of 9.36 mm at 13 mm applied displacement.
• The minimum stress amplitude achieved was 0.0264%.

Conclusions:

• The developed semi-open prosthetic socket can maintain constant interface pressure within a specific range of residual limb volume changes.
• The design offers benefits including light weight, effective heat dissipation, and adjustable sizing.
• This innovation promises enhanced comfort and functionality for prosthetic users.